HI Dave, Great to see you getting some traffic to this page, and to see there are people out there interested in saving these wonderful speakers. Keep up the good work !!
Thank you so much for the kind words, I've had to step away from my channel work for a while for as had deaths I'm the family etc. but I'll be back soon 🙂
yeah! mega pain to work on, especially if you aren't familiar with the design and it's your first time. When I did my first amp it was a real struggle, once I worked out a process it wasn't too bad. Thanks for dropping a comment!
I rebuilt my Penta 1s with kits from Martin about 6 months before you produced this video. At the time I couldn't find a video anywhere near as well done as yours. Great job ! I would have felt far more confident had i seen your video first !! Mine were very late in the production of the USA version of the Penta 1 and have many attributes of the Penta 2, including the later models crossovers, which i also rebuilt. One thing that jumped out at me, as i watched your video, is that neither of my amps had the glass isolators behind the transistors, OR i completely missed that they were even there ! You are the first i have heard ever make mention of them ! Most likely i passed right over that step without realizing :( Oh well, they will have to tolerate the old thermal paste behind them now ! Im not going back in there just for that ! When i had mine apart, the very first thing i did was clean all that thermal paste off everything as it was still wet, very messy and i was getting it everywhere. One thing i did differently - i didnt straighten the pins on the op amps. I was advised the tension would help keep them located in the bridge. Made them hard to get in, but ill wager they wont fall out !! Your rubber bushings on the transformer case were in far better condition than mine were. Martin sells those if anyone needs them. At 3:26:30 you are assembling the connection board with the two metal plates. These plates sit on black plastic posts that clip to the plate. My plastic posts were in terrible condition and i could not source them anywhere. I ended up dropping a blob of hot melt glue on them as a last resort. All went well and the speakers run and sound just fine, so i didnt mess up too badly ! Thanks again for a great video 👍
Thank you for the kind words. Sounds like you had a right battle on your hands with fragile parts on your amplifiers. It's interesting to head that your Penta 1s are closer to the Penta 2s than is usual. I'm sure all the revisions have more in common than we realise. I wonder if perhaps those posts could be 3D printed out of flexible plastic, I guess it would have to be somewhat flexible otherwise they would just crack. As you can see in my video I used some grease to ease the board back on. I can imagine if you're not careful they will always crack into pieces. I'm planning to do lots more B&O related videos in the near future so if you have any suggestions feel free!
@@TheRetroBristolian Not sure i can offer any worthwhile suggestions as you seem more competent than me. I rebuilt the midrange drivers and crossovers on my Pentas, but along with the amp rebuild, that is the extent of my experience with B&O products. If you do the midranges, Fred at Audiofriends has the best foam surrounds, he is wonderful to deal with, and as a bonus he is the only one i could find that has the thin gaskets that go between the midrange drivers and the mount baffle. Ill be following your videos with interest.
@@kiwiaudio8462 Thanks for the top tip on Audiofriends! I have actually purchased the mid foams from them back in July and they're sat in the box waiting to be opened! I will do a channel update soon and show this
Now THIS is a real restoration. Not like most of those "other" videos where they clean everything with an "ESD safe brush" and then put it back together, and call it restored lol.
Thanks for the kind comment! I put a crazy amount of effort into this video, it was important for me to try and catch all the information I could so the viewers had as much understanding as I did. Comments like this really help to encourage me to carry on and produce the next one 🙂 Thanks and take care.
@@TheRetroBristolian No problem! I am also restoring a pair of Penta 1's AND Penta 2's... interesting to see all the minute differences and changes between the two generations. In your opinion, which Gen is superior in sound quality? Is there any difference?
@@Johnathan_Waters That's tough, I'm not knowledgeable enough to be able to compare/define differences which would allow for superior quality between them, what I would say is that it depends on how you use the Pentas, for example the Penta 1 has RCA (which is fine for use with 3rd party sound sources), but if you want a real B&O experience with Powerlink and displays then either the Penta 2 or 3 is a better/more functional speaker because of that. the Speakerlink standard on the Penta 1s whilst sort of impressive it was also clunky. I personally would prefer either Penta 2 or 3 because of Powerlink, then it comes down to preference of if you like t he Penta 2 or 3 displays more. I believe in the late Penta 3 there could be some marginal difference to the amp, but other than that they are practically identical from what I understand. Sound improvements can be made by upgrading the little amp chip, using good quality capacitors, making sure your crossovers are re-capped also, using well shielded cables, making sure the foams on your mids aren't crumbling. I do believe the Penta is generally all round an impressive speaker, and depending on the use case an end user should be happy with any of them really. Hope that helps
Update: I saw a comment asking how to tell the polarity of the speaker cable - this is at time stamp 3:51:38 UPDATE: I have spoken with Martin at the beoparts-shop and he has provided the following clarifications: - The trim pots have their values stamped on the rounded top egde ("neck"). - The large PSU capacitors (filter caps) could potentially be fitted 180deg and clear the cage casing. (obviously follow cable/polarity). You could also push them into a more central position to stop them catching on the top cage housing. - I should have probably replaced the old foam with new foam! I've been asked about total cost of repair. This is a tough one to answer as it will vary on what parts you buy, what tools you already have etc etc. I'll try and summarise the big parts below: Crossover kit CK-004 £33 (not fitted) (ignored in total cost below) PSU Capacitor kit CK-082 £52 Amp Capacitor kit SK-003 £42 UK Plugs (2) £8 UK 3A fuses (2) £2 4Ma glass fuses (2) £4.62 Thermal paste £5.37 Transistor 1 (6) £22.92 Transistor 2 (6) £22.92 This gives an approx cost of repair for both amplifiers £160, making approx cost per amplifier of £80 in parts. Of course the transistors are NOT usually required, I have shown them for informational purposes and because that was what had failed on 1 of the Penta 1 amplifiers I originally repaired. If you didn't add them in, cost could be more like £114 total, £57 per amp.
This video has been a great help repairing a pair of mk1 6603. Though I ran into a problem if you had any input. I replaced all capacitors and got the amp to turn on and green light. Though trying to set my trimpots I have tried two different multimeters and can't get any reading from 1R103 and 1R104 pin. Also when clamped onto end of loudspeaker output is only reading in the 30s and isn't affected when I turn the screw. The light is green on the amp to.
it measures in millivolts DC from memory, if you have an auto ranging meter you might have to change from AC to DC, try adjusting the range on your meter, try probing something like a AA battery to make sure you can read a smallish DC voltage. Thanks for dropping by, great to hear the video was helpful
Hi David and thank you for the incredibly insightful video. I’d like to share a problem I’m having after the rebuild (which I did with my Danish partner for good karma). We’ve completely rebuilt the amp using the BEO Parts Shop kit and are ready to power it on. When applying power we’re seeing a red standby-light, then as we move the source slider to LINE, the status light turns green, then blows the T5A fuse. We’re going to start tracking the problem down, but before we start digging, I thought I’d check and see if something obvious jumps to mind. We’ve followed your instructions to the letter which has been invaluable and for which we are eternally grateful. Cheers, Jens.
Hi Jens, Sorry for the delay in a reply, I've got a lot going on personally right now sadly. If you're blowing the T5A fuse that's the main fuse for the larger transformer this isn't a problem I've had before. I'm assuming one wasn't rebuilt/still works? My advise would be to check across the windings and see if the resistance seems similar between the transformers in the Pentas, you're checking for a direct short/strangely low resistance I guess (might show a cut/short in the windings of the transformer.) After that I would check the relay to make sure it is switching OK and not stuck in some way, then check the Diodes around it. Another logical problem could be that the actual amp/boards are trying to draw far too much power through a short. I assume the speaker worked before you did the rebuild? Have you checked carefully all the values you replaced was like for like, checked the orientation etc? I would think there is a short somewhere, so use a multimeter and poke about in continuity/resistance mode and see if you spot anything odd - compare a working and non working amp. Do you have the service manuals? My email address is on my channel about if you'd like me to email them across. Hope you have success soon! Many thanks, David
There's enough slack left (incl. the link plus to minus) to solder the original wires back on those big caps isolated with red and black heatshrink tubes. Good job again Dave. Working on 18 of those bastards now.....
Hi Leslie, Happy New Year. I've been following your pictures on Facebook, that's a lot of capacitors to replace! Glad RUclips has finally woke up and is allowing you to post on my videos all the time now, really unsure what happened with your first few posts. Take care - I'll drop you an FB message soon about some other bits.
Do you have have an extended cut of this video? 😂 Very good tho the level of detail is unreal. I'm sure this will help of a lot of people out there. Keep up the good work
very informative! my Dad recently got some refurbished beolab penta mk3 and unfortunately has developed a fault where the right speaker entirely cuts out while the left carries on as normal. they are daisy chained with powerlink cables with the right speaker (faulty one) is the beginning speaker. after a bit of troubleshooting we have found it to "come back to life" when the power cord near the base is given a litttle wiggle....looks like a loose connection from the power cord but neither me or my dad have the technical ability to remove things or considder soldering anything!? apart from sending it to B&O specialists, what would you recommend for someone living in the west UK? sounds like it could be an easy fix but my dad daren't open them up
again awesome thanks again, just a tip to access the nut on Bridge rectifier through hole in side panel behind Door, no need for flexi extension regards Brad
Hi Brad, Thanks for the comment and kind words and an even bigger thanks for the 'buy me a coffee' funds! This isn't expected or demanded, but is truly appreciated. I woke up this morning to the emails about both and that was a really lovely gift to wake up to :-) Finally on your comment about the hole in the side panel - great spot! This is what the comment section is all about, spotting the missing information and adding it into the mix! If not already, consider hitting subscribe (it's free) as I'll have upcoming videos on recapping the crossover boards and re-foaming the mid ranges.
Fantastic job, thanks Dave. I bought the capacitor kit from Martin back in 2019 but wasn't confident enough to attempt it, but thanks to you I just might. BTW, I'm thinking of using Akasa's double sided adhesive thermal pad for the transistors instead of messy TIM/glass isolator/messy TIM.
Hi, thanks for dropping by with a comment. I'm really pleased to hear the video might help you to give it a try, just take your time and maybe practice your soldering skills first if It isn't something you often do 🙂 Ref the thermal pads, I did consider this but thought it safer to replace it all as per original design, I'll be interested to hear how you get on with the thermal pads! Hopefully they do the job well for you and it could be a good option for others to use. Thanks and take care,
Excellent detailed video, top marks! I have a couple of questions: I've moved a pair of Penta Mk 2s from USA (120V) to NZ (240V). I have the service manual showing how to restrap the transformers for 240V, and it mentions the change in glass fuse ratings; are you aware of any other 'gotchas!' when changing supply voltage to Penta amps? One of my pair is, annoyingly, missing the plastic cover from the digital display; are you aware of any source for a replacement? Beoparts have nothing :-(
Hello, I have a problem with one of my beolab penta mk. 3 6631, I hope you can help me. One of them is having a humming noise from the amplifier, not from the speakers, only the amplifier. Is is like a small electric humming, not a deep sound. It doesn’t amplify when the volume increases. And usually it starts after I have used it for a little while. Newer when I turn it on when it’s “cold”. They are both speakers running at 56 degrees Celsius. When I have been pushing them at high volume. They overall sound great. I bought them, and tried them shortly to see if they worked, then I refurbished the 4 midranges in both speakers. So after that, I noticed the fault. Are they doomed? Did I mess up the wirering? I really need some expertise. Thanks for some great videos. Best regards Ben
How would they sound better, connecting them via RCA to a sound amplifier for example onkyo or eliminate the lower amplifier and leave them as passive?
I really depends on how you plan to use them and if your amplifiers have been serviced. some people really rate the Beovox Penta (non amplified) with a beefy external amplifier, and other people swear by the convenience of the Beolab Penta (amplified). in my setup the Beolab is better as I have a lot of B&O equipment, but your use case may be different. Thanks for the comment :-)
They are Burr-Brown operational amplifiers (ICs) Off hand I'm not sure I wrote it down the model and I don't want to give away all the secrets of the kits. I believe there are forum posts about it though. Hope that helps.
Thank you so very much for this video. Currently at 3:39:47 mark and have been enjoying every second of it. I bought the kits from Martin, and even though the schematics that came with were really good, I was unsure on how to do for example the trim pots in his amp kit. No more. Finally I can get the rest of my penta project finished. I'm so grateful for this video. I've learned so much from your video so far, not just the repair part, but the science behind it to. Also I really appreciate you linking all of your equipment. A million thanks. A small question I was wondering if you could answer. On my first teardown of the amp, I broke one of the "glass panels" that acts as a heatsink for the transistor. Do you have any suggestions on what I could use to replace it with? Thanks again.
Hi Steinar Oen, Thank you for the kind words and lovely message. It was great to read that first thing this morning! Thank you also for supporting me with the 'Buy me a coffee' link. I've had a further look into this and feel silly for having left it out of the video, the large transistors are TO-264 style. If you google TO-264 insulator sheet you should find what you're looking for. However if you search for TO-247 insulator sheet, these seem to be more common and I 'think' are the same dimensions. Please check it against the size of your originals as I don't have mine to hand to check measurements. If you need any further help please comment again, if you haven't already, please consider subscribing as I will be posting more B&O related content soon. Finally, I have various Beovision, Beocenter, Beosystem and Beolab speakers, I'm also considering doing videos on Datalink, Speakerlink and Powerlink in the future. Is there anything you would be interested in? Thanks,
@@TheRetroBristolian Thank you so much for your reply Dave. Rest assured I have both liked the video and subscribed. I am very excited and looking forward to your future content. This is great. I am currently looking into the insulator sheets, a million thanks. Thanks to you I now feel confident that I can breathe new life into my Pentas and I am beyond excited about it. Did you have a hard time refitting the switches? I had a little hard time getting them back in place the first time I was inside the amp, and just yesterday I tried to switch the modes and one of them fell down into the amp, so I have to refit it again. My Pentas no longer go into auto standby when it hasn't received any signal for a while. They used to before. I had them set to left/right, and tried changing to auto (how my switch fell into the amp) to see if they then would go into standby. It didn't help. What's worse is that when set to auto they, didn't even output anything at all. Do you have an idea why they no longer wanna go into standby automatically after a while? Regarding the popping when they power on. I googled this "problem", and there seems to be a fix to it, but the google result sadly was an old forum post which did no longer contain the information on how to fix it. I am still looking for a way to get rid of that popping sound. One thing that really piqued my interest when you were showing your awesome setup, was your subwoofer. Is this by any chance connected to your Pentas? If so, how did you connect it? I would love to see you talk more about it in future content - but if you wouldn't mind explaining it in a reply, I would really appreciate it. Honestly I would be interested in any content with the B&O products you mentioned. I am very new to the world of B&O, so I have very little knowledge about their products. For personal reasons I have always wanted a pair of the Beolab Penta, and while researching repairs online I have learned a little about their history, and would love to know more about the Beolab lineup. To put it like this: I watched your video from start to end. You explain things detailed and clearly and you obviously have a passion and knowledge of what you're doing. I can't speak for others, but that captivates me at least. I would want more of all of that. Once again, thank you so much for all of your help. Take care and have a good one!
@@raz0r2k Sorry for the delayed response! You’ve asked quite a lot of questions there so let me try my best to respond. In regard to the switches, YES! I would highly recommend not disassembling these front panels unless you absolutely must. For me I found have the panel casing flat on a table, tilt the lower edge up and place the switches into the casing, seat them in well and make sure it is at a steep enough angle they will stay put. Try and have them all at a central position and set the physical switches on the board to central positions. Have a friend adjust and shine a light down into the case/switch hat area. Now try and angle/lower the PCB down in. There will be a lot of trial and error and you will need just the right angle and amount of light to do it, but it is possible. I had the opposite of the standby issue, one of my amps wouldn’t come out of standby, it turns out I didn’t connect the front door properly, so you have to make sure the ribbon is lined up with the connectors and all the pins match. For your issue however I think I have read about this, there is a relay on a small board next to the large capacitors under the transformer, that is the on/off relay I believe and sometimes they can stick. Have you looked at the service manuals? Do you hear the relay clicking on and off at plug in? Regarding the power up pop through the speakers. I did a bit of a google recently myself and found the correct information. Essentially you need to add some additional circuitry to allow a small load to pass into the capacitors and charge them, this then stops the pop. You can simulate the effect of this by turning the speakers on for a few minutes, turn them off for half a minute and then turn them back on. You should notice no or a very minor noise. I may cover how to do this circuitry in the future in another video. In regards to the Penta/BL2 (Sub) setup it all goes through the Avant 55, they are all connected separately via PowerLink to the TV. If you don’t have that sort of setup the BL2 does have Powerlink in and out and via the switches on the back of it you can set the crossover bass filter and route main sound to the Pentas by the output of the of the BL2. Hopefully this makes sense. I’ll 100% be adding more content and covering more of the beolab lineup in repairs and reviews in the future. Thanks again,
Hello, thank you for this wonderful vidéo. I have a pair of penta 2 speakers, which have the same problem, when plugged in, it goes straight to yellow ???
I would always recommend doing the cap kits on these amplifiers, I did this first on my friends Penta1s and sadly one amp still went straight to yellow, that ended up being due to one of the large transistors failing. I talk about this here 2:52:33 it might be worth using a multimeter to test/check for shorts as I show. Let me know how you get on and good luck!
Best tutorial ever seen. Just wondering why you haven't used heatshrink tubes on the AC fuse wiring to support the soldered cables. You did it on the powercaps so why not here. AC wires (220V!) can break easily on those solder joints.
Hi Leslie, Thank you for the kind words, question and accidental phone call this afternoon! You're absolutely right, using heatshrink on the AC wiring to the fuse holders would be a great additional to the guide/process. From memory I 'think' I did this on my second amp, but by the time I got to the end of this 5 Day plus recording session in a record UK heatwave I was getting a bit tired! I would absolutely say this is a worth while task. It was great to talk on the phone and compare thoughts on various B&O topics. Perhaps at sometime in the future we could do a call/discussion on the channel? I look forward to making more content again soon and showing the Beolink 7000 panel you kindly sent over. All the best.
Hello, great video. I just picked up a pair of beo lab Penta 2 they were working just fine until the right speaker stopped working. I just have the amber light and cannot play anything though it any longer. What can I do to fix them? Thank you
Hi, if you are getting what B&O call the yellow light then the amplifier has activated its protection circuit. It will do this when it notices a fault. I saw this on a Penta 1 and it was down to the large transistors, my best advice is to follow the video and recap the amp as they all need that service usually now. but pay attention to my transistor checks section. with the bottom of the amp off you could use a simple multimeter in continuity mode and check for shorts across the 3 pins of each transistor - that was the fault on a Penta 1 as show in that section with the internally shorted transistor. Thanks for the comments and good luck
Thank you for sharing your knowledge and time!! I have a buzzing sound coming out of one of my pentas. I am low tech but willing to roll up my sleeves and learn. Can you give me some ideas on how to get started with troubleshooting? I have not yet gone through your video, so would appreciate your advice on how to go about it and if you can highlight the parts to pay special attention to. Thanks again.
Hey, Thanks for the kind words, It very much depends on the type of buzz and where it is coming from, it could be a loose connection, could be the particular input you are using. First think I would try (if it's only on one speaker) is switch the amps around, does the buzz follow the amp or the speaker? next is change which input you are using and maybe the device you are sending to the input. Again, you're looking to see what part the buzz follows. I did notice when I rebuilt my friends Penta 1s that before the rebuild there was a buzzing/crackling intermittently, the rebuild fixed this. Hopefully you can track the buzz down and see if an amp rebuild would be a good idea. Please do let me know how you get on. Many thanks, David
Hi. Just came across your vid. Excellent by the way. My penta 3,s have an issue. They both work and displays are on but when i turn them into standby mode one goes red and the other goes yellow. Have you any idea what the issue could be
The Penta 3 manual says: The Beolab Penta is equipped with a protection circuit which is automatically activated if something is wrong, e.g. - if the amplifier unit is overheated, - if a fault occurs in the amplifier which could damage the loud- speaker units. If the protection circuit is activated, the sound disappears and the light on the front of the amplifier turns yellow. at 2:52:56 in the video I discuss about on my friends Penta 1s one was stuck in yellow protection circuit due to a shorted transistor, it sounds like yours isn't as faulty as his was, but if they haven't been serviced, doing a cap kit won't hurt, reflow of critical solder points to see if it improves the situation, I'm really sorry I don't have a 'smoking gun' answer for why your particular amp is doing this. Best of luck.
Hi Dan, It would very much depend if you are local or plan to post the amps as that would be costly, also as you can see from the video it is many hours work to do. I would consider doing repair/refurbishment work sometimes, but sadly I am quite busy personally at the moment with one thing and another, is this not something you feel comfortable doing yourself? Thanks,
Great video! I'm currently trying to sort a problem with a Mk I amp. Amp powers on fine, and switches green with signal. Issue is output starts at correct volume for a split second when switching on, then drops to a whisper?! You can just hear the sound. I've checked the inputs (RCA and Speaker Link have the same issue), I've tested the PCB relay, and the main capacitors (which seem to have been replaced at some point), and all test OK. Can you advise where else might be worth looking at for this issue?
It's a tricky one, As I say this isn't my day job. I wonder if changing the OP-AMP chip as shown in my video would make any difference. RCA would be my preferred connection for testing. have you checked the voltages as shown at the end of my video to make sure the amp is 'calibrated' OK? Also just check none of the caps are back to front/incorrect values. Keep us posted how you get on. thanks,
If you mean the front door won't lock into the latch shut and keeps sliding open, then that is covered at 56:29 you will need to replace the latch. If that isn't what you mean, please explain in more detail. Thanks for the comment.
Hi David. We have been left a B&O Beocentre system from late parents. Like many of your previous viewers we also would like to thank you for 5 hours plus of your time to help us all. We also have a speaker that is out of action. Can you please advise where I can source the appropriate fuses? Do you offer a repair service? Many thanks again. Stephen
Hi Stephen, Thank you for the kind comments and I'm sorry to hear about your late parents. All links for kits, fuses, parts used are in the video description if you expand it and scroll through. Although I didn't replace the 2A fuse so I don't believe there is a link for that. I didn't do this video to self promote as a repair service, but I have had 4 or 5 people now ask this question! I would be willing to offer a repair service infrequently if it helps some people, but obviously my hope is to share knowledge and inspire others to perform successful repairs themselves. I can be reached privately through RUclips@theretrobristolian.co.uk If you would like to discuss options. Thanks, David
Hi, I have a pair of speakers. bang olufsen model 6603 and I want to know how to connect a player, TV or amplifier since it only has red and black cable inputs on the bottom and only one RCA type input.
for the Penta 1 which you have you want to use the singular RCA inputs. on your TV or amp you might have left and right pre-outs or a headphone jack, you run from that to RCA jacks and just use the speakers as a left/right pair. on the little panel at the front of the amp you pop it open and move the switch to auto I believe. You should notice the amps turn on when they detect signal and will eventually turn off when the signal goes. I would highly advice you read the Penta 1 manual to become familiar with the speakers. always set your input to very low volume to start with as not to damage the speakers and become familiar with how they will work in your setup - thanks for the comment and dropping buy.
@@TheRetroBristolian in the lower part it only has two holes to introduce a red and a black cable and it is only one RCA not two as they are normally used.
@@TheRetroBristolian hello, good afternoon, excuse the amplifier that comes with these speakers, can they be eliminated and use the speakers as passive and connect them to an amplifier?
@@enriquealvarez3157 Yes, if you remove the amplifiers following the steps shown in my video you can connect speaker wire straight to the screw terminals on the speakers directly to an external powered amp like an AVR etc. to reattach the base you will need some small bolts to replace the long spikes the amp slides over. Some people prefer them as Beovox passive speakers. I believe you do need quite a powerful amp for them to sound their best.
hi , only you can help me because you know the mk3s like the back of your hand, basically I sent the midrange panels to a specialized center to renew the suspensions, unfortunately when I removed them I didn't catalog the wires with the various colors, I was wondering if you could give me a hand. Greetings from Italy
This is brilliant. I am the original owner of a pair of Beolab Penta 1 speakers. They still work and sound great, even though I know the foam in the mid-range speakers becomes an issue eventually. My only issue is that one speaker is running hotter than the other. It hasn't triggered the yellow fault light yet but the outside case on the affected amplifier gets pretty hot with sustained use compared to the other speaker that just gets warm. Thoughts on the most likely cause of this issue and the potential fix? One enthusiast told me trim pot adjustment may due the trick. Other thoughts?
if the amps are working you can of course skip to the trim pot calibration part in my video and follow that. I would say (especially if Penta 1s), that a cap kit is going to be required. The caps used originally weren't all that great and are well past their use by date and could be slowly leaking/weeping like shown in my video. Take care and good luck!
I've the Mk2 model, but from one of them not heard nothing audio, but the Red light of amplificator is on. What is the problem? Should be one of 2 internal fuse burn? Who help me?
Hi again Dave. I am unsure if you got a notification from my reply to your reply on my other post, so I'm writing to you again hopefully to get your attention. I am very interested in knowing how you were able to connect your subwoofer to your Pentas, and would really appreciate any guidance on how to do this. Take care.
Thumbs Up for the great detailed video. I've recently purchased a penta mk 2 as well and the seller informed me he removed the amplifiers from the speakers due to one of them having imbalanced output volume. I have yet checked the amplifier on the issue. Will you be able to guess what could be the possible issue since you're more experienced on penta repair? Also I'm actually considering getting my own capacitors to replace the old ones. In your video, on the powerpoint that showed the capacitor values, is there a mistake on the ones showing -10 +100%? As far as I know, usually its a + - 10% or + - 20% on capacitors. Please correct me if I'm wrong here.
Hi Keith, Thanks for the comments and congrats on your Penta Mk2 purchase! One of my friends Mk1s had muffled and distorted sound, the capacitor replacement brought it back to perfect clarity so simplistically I would guess its due the capacitors replacement. I admire you wanting to source your own capacitors and no doubt its doable and there are some great brand capacitors out there, but I would like to explain/make one point. What we have here is a community of very passionate people that love their hobbies and love the B&O product line. Without people like Martin at the BeoParts-Shop I would have never had the confidence to attempt this repair. I'm a great believer in supporting the community, inspiring others, and giving back to those that helped me along the way. You are well within your rights to do as you see fit and use my video as you see appropriate, but I would ask you to consider a) the safety of Martin's kits and knowing they work brilliantly and b) supporting that community by supporting the people keeping it alive with new and exciting repair kits and upgrade kits. When it comes to the capacitor values I've listed, I'll have to correct you if you're wrong I'm afraid! I totally agree it is a VERY odd tolerance to see and not something I've ever come across before doing this (but then I am relatively young/new to the process). I took all values straight from the B&O service manuals and on further research -10/+100% is known as the W tolerance. Further reading can be found on this site: www.iequalscdvdt.com/Markings_and_Codes.html Thanks again for the comments and view, please consider subscribing as I'll be doing the crossovers and mid foam replacements later in the year.
@@TheRetroBristolian Hi, Dave. Thank you for the prompt reply on my queries. I've visited Martin's website and added some of the kits to cart. Will definately support a fellow enthusiast. I'm just hoping to source for better capacitors as I'm not sure what capacitors martin are supplying (I'm quite a supporter on nichicon and Elna caps). 😅 Do hope to see more great videos from you soon. Cheers man 😎👍
@@TheRetroBristolian I've gotten the amp recap kit from martin via ebay. Changed the caps but my amp doesn't goes into green light(on mode). No voltage during the dc voltage trimpot check. Connecting to the speaker wire shows a -67mv... Not sure if it's the faulty transistors 😫
@@keithchua5840 Hi, Sorry to hear this. OK so back to basics, did it go into green light mode BEFORE the work you did? Has it ever gone to a yellow light mode 'fault'? If it used to go green and now doesn't check the ribbon cables to the door are lined up with the pins on the board perfectly. When I did my second amplifier I accidentally got it one pin over and this stopped it turning on! Try toggling from off to auto on the door a few times, try leaving it unplugged, switch to auto and then plug in with it already on auto. You could also try attaching an audio source to it you don't mind breaking if there is something seriously wrong. My final thought is switch the doors between the amplifiers to confirm that there isn't a fault in the door circuitry. In regard to the transistors, do the pin to pin continuity check across them all to see if there appears to be any shorts (as shown in the video) you could carefully desolder them and do the out of circuit checks also shown in the video before purchasing new ones. Hope this helps
Hi David. İ have problem with my beolab penta 2 like in this video. Problem is the one speaker sounds more quietly than second one. Can u help me? What do u think it can be? Thank u! Like for this video.
Hey Ahmet, thanks for dropping by and leaving a comment. that sounds somewhat similar to a problem I had on my friends Penta 1s. It ended up being dried out caps that needed to be replaced, one speaker sounded muffled and distant where as the other (that I had just rebuilt) sounded present and really in the room with you again. Just to rule out other issues first though, have you tried switching the cables between the good and the bad speaker? have you tried switching which output of your amplifier/input device you are using? Perhaps if you have a different device entirely, have you tried using RCA over Powerlink etc and toggling the switches? If you rule out cable and device issues and the problem still persists on the one speaker we can assume the speaker is faulty in some way. the next thing to do would be to switch the amps between the speakers (as in the bottom boxes) and see if the fault follows the amp or the speaker, from there you will know if the amp needs work or perhaps a speaker is blown or the crossover in the speaker needs work. I hope this helps and good luck with your speakers in the future!
@@TheRetroBristolian i made everything what u wrote, change cables etc. i will check the caps that u change in this video. Because when i ON speaker after 2 days it works good and after few minutes it again start sounds quietly. By the way thank u again for your response. Take care.
Hi David. Me again) i change all caps, it works better, but now high frequency sound a little bit lower. I think it can be trimpots. Maybe u have some ideas about this problem? Sound comes like under the pillow😅 Not enough clear and saturated. Thank u very much!
@@axmetmeredov hummm I hear it's best to replace the trim pots, but you should with the amp off wipe them back and forth multiple times to clear any potential surface film off them and then resetup the amp following the steps I show towards the end of the video - did you make sure to set the trim pots? If the sound is still muffled did you switch the amps between the speakers to see if the problem follows the speaker or the amp? it is always possible the crossover in the speaker needs work or that the mids need refoaming perhaps. If I were you I would just want to make absolutely sure that the problem is with the amp and not something in the speaker. Let me know how you get on.
@@TheRetroBristolian yeah i already switch the amps, and this is not the speakers, also i calibrate the trim pots like u show on this video, but i don’t change them yet. When i calibrate a trim pots, the 30v works good and second one which 4v works incorrect when i calibrate it. I will change the trimpots and let u know. Can it be the opamp?
Hi, I'm sorry I don't speak Spanish sadly and google translator says "When the transformer votes" - this doesn't really make sense to me? are you able to comment in English or try and translate to English? Thanks
it's not a commercial thing for me, it's more that Beoparts-shop (Martin) has put time into making and selling the kits to the community, without his kits my video wouldn't exist so i'm just trying to be respectful of him and his business - hope that makes sense
Thanks for the comment. have you tried switching the speakers around? So connect the left cable to the right speaker and right speaker to the left? That way you can hopefully rule out the amplifier and cables IF the problem follows the speaker. once you have found your troublesome speaker you can then try some of the different inputs on it, toggle the switches in the amp back and forth a bit. If this doesn't help, now switch the amplifiers on the speakers around and see if the fault follows the actual speaker or the amplifier. if its the amplifier then it will need repair like I have shown in this video. Hope that helps.
![Bang Olufsen Beolab Penta speaker upgrades - 6 simple hacks for better B&O sound [4K]](http://i.ytimg.com/vi/6sikXyjKlp4/mqdefault.jpg)
I just replaced a fuse in one of my Penta's. Amazing vid. Could not have done this without it. Thanks!
Thanks for the lovely comment! Hearing stories like this is why I put the effort into making the video. Great to hear it was of help to you. Thanks.
Excellent work David
Thanks for the feedback
Thank you very much for this video. It must have been a big big work to do.
Thank you for the kind words! it was a big job, but well worth the effort!
Many thanks for this valuable instruction!
It was a very usable guide for me to disassemble my Penta 6631 and service it.
Thanks for dropping by with a comment, really glad you found the video helpful!
HI Dave, Great to see you getting some traffic to this page, and to see there are people out there interested in saving these wonderful speakers. Keep up the good work !!
Thank you so much for the kind words, I've had to step away from my channel work for a while for as had deaths I'm the family etc. but I'll be back soon 🙂
The mechanical design of that amplifier is gorgeous!! Looks great, a bit of a pain to work on 😂
yeah! mega pain to work on, especially if you aren't familiar with the design and it's your first time. When I did my first amp it was a real struggle, once I worked out a process it wasn't too bad. Thanks for dropping a comment!
I rebuilt my Penta 1s with kits from Martin about 6 months before you produced this video. At the time I couldn't find a video anywhere near as well done as yours. Great job ! I would have felt far more confident had i seen your video first !!
Mine were very late in the production of the USA version of the Penta 1 and have many attributes of the Penta 2, including the later models crossovers, which i also rebuilt.
One thing that jumped out at me, as i watched your video, is that neither of my amps had the glass isolators behind the transistors, OR i completely missed that they were even there ! You are the first i have heard ever make mention of them ! Most likely i passed right over that step without realizing :( Oh well, they will have to tolerate the old thermal paste behind them now ! Im not going back in there just for that !
When i had mine apart, the very first thing i did was clean all that thermal paste off everything as it was still wet, very messy and i was getting it everywhere.
One thing i did differently - i didnt straighten the pins on the op amps. I was advised the tension would help keep them located in the bridge. Made them hard to get in, but ill wager they wont fall out !!
Your rubber bushings on the transformer case were in far better condition than mine were. Martin sells those if anyone needs them.
At 3:26:30 you are assembling the connection board with the two metal plates. These plates sit on black plastic posts that clip to the plate. My plastic posts were in terrible condition and i could not source them anywhere. I ended up dropping a blob of hot melt glue on them as a last resort.
All went well and the speakers run and sound just fine, so i didnt mess up too badly !
Thanks again for a great video 👍
Thank you for the kind words. Sounds like you had a right battle on your hands with fragile parts on your amplifiers. It's interesting to head that your Penta 1s are closer to the Penta 2s than is usual. I'm sure all the revisions have more in common than we realise. I wonder if perhaps those posts could be 3D printed out of flexible plastic, I guess it would have to be somewhat flexible otherwise they would just crack. As you can see in my video I used some grease to ease the board back on. I can imagine if you're not careful they will always crack into pieces. I'm planning to do lots more B&O related videos in the near future so if you have any suggestions feel free!
@@TheRetroBristolian Not sure i can offer any worthwhile suggestions as you seem more competent than me. I rebuilt the midrange drivers and crossovers on my Pentas, but along with the amp rebuild, that is the extent of my experience with B&O products. If you do the midranges, Fred at Audiofriends has the best foam surrounds, he is wonderful to deal with, and as a bonus he is the only one i could find that has the thin gaskets that go between the midrange drivers and the mount baffle.
Ill be following your videos with interest.
@@kiwiaudio8462 Thanks for the top tip on Audiofriends! I have actually purchased the mid foams from them back in July and they're sat in the box waiting to be opened! I will do a channel update soon and show this
THANK YOU FOR THIS AMAZING VIDEO! Please make a video showing how to refurbish the crossovers next :)
Now THIS is a real restoration. Not like most of those "other" videos where they clean everything with an "ESD safe brush" and then put it back together, and call it restored lol.
Thanks for the kind comment! I put a crazy amount of effort into this video, it was important for me to try and catch all the information I could so the viewers had as much understanding as I did. Comments like this really help to encourage me to carry on and produce the next one 🙂 Thanks and take care.
@@TheRetroBristolian No problem! I am also restoring a pair of Penta 1's AND Penta 2's... interesting to see all the minute differences and changes between the two generations. In your opinion, which Gen is superior in sound quality? Is there any difference?
@@Johnathan_Waters That's tough, I'm not knowledgeable enough to be able to compare/define differences which would allow for superior quality between them, what I would say is that it depends on how you use the Pentas, for example the Penta 1 has RCA (which is fine for use with 3rd party sound sources), but if you want a real B&O experience with Powerlink and displays then either the Penta 2 or 3 is a better/more functional speaker because of that. the Speakerlink standard on the Penta 1s whilst sort of impressive it was also clunky. I personally would prefer either Penta 2 or 3 because of Powerlink, then it comes down to preference of if you like t he Penta 2 or 3 displays more. I believe in the late Penta 3 there could be some marginal difference to the amp, but other than that they are practically identical from what I understand. Sound improvements can be made by upgrading the little amp chip, using good quality capacitors, making sure your crossovers are re-capped also, using well shielded cables, making sure the foams on your mids aren't crumbling. I do believe the Penta is generally all round an impressive speaker, and depending on the use case an end user should be happy with any of them really. Hope that helps
Update: I saw a comment asking how to tell the polarity of the speaker cable - this is at time stamp 3:51:38
UPDATE:
I have spoken with Martin at the beoparts-shop and he has provided the following clarifications:
- The trim pots have their values stamped on the rounded top egde ("neck").
- The large PSU capacitors (filter caps) could potentially be fitted 180deg and clear the cage casing. (obviously follow cable/polarity). You could also push them into a more central position to stop them catching on the top cage housing.
- I should have probably replaced the old foam with new foam!
I've been asked about total cost of repair. This is a tough one to answer as it will vary on what parts you buy, what tools you already have etc etc. I'll try and summarise the big parts below:
Crossover kit CK-004 £33 (not fitted) (ignored in total cost below)
PSU Capacitor kit CK-082 £52
Amp Capacitor kit SK-003 £42
UK Plugs (2) £8
UK 3A fuses (2) £2
4Ma glass fuses (2) £4.62
Thermal paste £5.37
Transistor 1 (6) £22.92
Transistor 2 (6) £22.92
This gives an approx cost of repair for both amplifiers £160, making approx cost per amplifier of £80 in parts. Of course the transistors are NOT usually required, I have shown them for informational purposes and because that was what had failed on 1 of the Penta 1 amplifiers I originally repaired. If you didn't add them in, cost could be more like £114 total, £57 per amp.
This video has been a great help repairing a pair of mk1 6603. Though I ran into a problem if you had any input. I replaced all capacitors and got the amp to turn on and green light. Though trying to set my trimpots I have tried two different multimeters and can't get any reading from 1R103 and 1R104 pin. Also when clamped onto end of loudspeaker output is only reading in the 30s and isn't affected when I turn the screw. The light is green on the amp to.
it measures in millivolts DC from memory, if you have an auto ranging meter you might have to change from AC to DC, try adjusting the range on your meter, try probing something like a AA battery to make sure you can read a smallish DC voltage. Thanks for dropping by, great to hear the video was helpful
Hi David and thank you for the incredibly insightful video. I’d like to share a problem I’m having after the rebuild (which I did with my Danish partner for good karma). We’ve completely rebuilt the amp using the BEO Parts Shop kit and are ready to power it on. When applying power we’re seeing a red standby-light, then as we move the source slider to LINE, the status light turns green, then blows the T5A fuse. We’re going to start tracking the problem down, but before we start digging, I thought I’d check and see if something obvious jumps to mind. We’ve followed your instructions to the letter which has been invaluable and for which we are eternally grateful. Cheers, Jens.
Hi Jens, Sorry for the delay in a reply, I've got a lot going on personally right now sadly. If you're blowing the T5A fuse that's the main fuse for the larger transformer this isn't a problem I've had before. I'm assuming one wasn't rebuilt/still works? My advise would be to check across the windings and see if the resistance seems similar between the transformers in the Pentas, you're checking for a direct short/strangely low resistance I guess (might show a cut/short in the windings of the transformer.) After that I would check the relay to make sure it is switching OK and not stuck in some way, then check the Diodes around it. Another logical problem could be that the actual amp/boards are trying to draw far too much power through a short. I assume the speaker worked before you did the rebuild? Have you checked carefully all the values you replaced was like for like, checked the orientation etc? I would think there is a short somewhere, so use a multimeter and poke about in continuity/resistance mode and see if you spot anything odd - compare a working and non working amp. Do you have the service manuals? My email address is on my channel about if you'd like me to email them across. Hope you have success soon! Many thanks, David
Fantastic work. Thanks for taking the time to do this.
Thanks for the kind words :-)
There's enough slack left (incl. the link plus to minus) to solder the original wires back on those big caps isolated with red and black heatshrink tubes.
Good job again Dave. Working on 18 of those bastards now.....
Hi Leslie, Happy New Year. I've been following your pictures on Facebook, that's a lot of capacitors to replace! Glad RUclips has finally woke up and is allowing you to post on my videos all the time now, really unsure what happened with your first few posts. Take care - I'll drop you an FB message soon about some other bits.
Do you have have an extended cut of this video? 😂 Very good tho the level of detail is unreal. I'm sure this will help of a lot of people out there. Keep up the good work
Thanks for the comment! ha, if I get a hundred subscribers before the end of the year I will post an outtakes video!
very informative! my Dad recently got some refurbished beolab penta mk3 and unfortunately has developed a fault where the right speaker entirely cuts out while the left carries on as normal. they are daisy chained with powerlink cables with the right speaker (faulty one) is the beginning speaker. after a bit of troubleshooting we have found it to "come back to life" when the power cord near the base is given a litttle wiggle....looks like a loose connection from the power cord but neither me or my dad have the technical ability to remove things or considder soldering anything!? apart from sending it to B&O specialists, what would you recommend for someone living in the west UK? sounds like it could be an easy fix but my dad daren't open them up
Thnx a Milion Dave
Super great video
Thanks for dropping by and leaving a comment, glad you enjoyed it, take care.
again awesome thanks again, just a tip to access the nut on Bridge rectifier through hole in side panel behind Door, no need for flexi extension regards Brad
Hi Brad, Thanks for the comment and kind words and an even bigger thanks for the 'buy me a coffee' funds! This isn't expected or demanded, but is truly appreciated. I woke up this morning to the emails about both and that was a really lovely gift to wake up to :-)
Finally on your comment about the hole in the side panel - great spot! This is what the comment section is all about, spotting the missing information and adding it into the mix!
If not already, consider hitting subscribe (it's free) as I'll have upcoming videos on recapping the crossover boards and re-foaming the mid ranges.
Fantastic job, thanks Dave.
I bought the capacitor kit from Martin back in 2019 but wasn't confident enough to attempt it, but thanks to you I just might.
BTW, I'm thinking of using Akasa's double sided adhesive thermal pad for the transistors instead of messy TIM/glass isolator/messy TIM.
Hi, thanks for dropping by with a comment. I'm really pleased to hear the video might help you to give it a try, just take your time and maybe practice your soldering skills first if It isn't something you often do 🙂
Ref the thermal pads, I did consider this but thought it safer to replace it all as per original design, I'll be interested to hear how you get on with the thermal pads! Hopefully they do the job well for you and it could be a good option for others to use.
Thanks and take care,
Excellent detailed video, top marks!
I have a couple of questions:
I've moved a pair of Penta Mk 2s from USA (120V) to NZ (240V). I have the service manual showing how to restrap the transformers for 240V, and it mentions the change in glass fuse ratings; are you aware of any other 'gotchas!' when changing supply voltage to Penta amps?
One of my pair is, annoyingly, missing the plastic cover from the digital display; are you aware of any source for a replacement? Beoparts have nothing :-(
Hello, I have a problem with one of my beolab penta mk. 3 6631, I hope you can help me.
One of them is having a humming noise from the amplifier, not from the speakers, only the amplifier.
Is is like a small electric humming, not a deep sound.
It doesn’t amplify when the volume increases. And usually it starts after I have used it for a little while. Newer when I turn it on when it’s “cold”.
They are both speakers running at 56 degrees Celsius. When I have been pushing them at high volume.
They overall sound great. I bought them, and tried them shortly to see if they worked, then I refurbished the 4 midranges in both speakers. So after that, I noticed the fault.
Are they doomed? Did I mess up the wirering? I really need some expertise.
Thanks for some great videos.
Best regards
Ben
How would they sound better, connecting them via RCA to a sound amplifier for example onkyo or eliminate the lower amplifier and leave them as passive?
I really depends on how you plan to use them and if your amplifiers have been serviced. some people really rate the Beovox Penta (non amplified) with a beefy external amplifier, and other people swear by the convenience of the Beolab Penta (amplified). in my setup the Beolab is better as I have a lot of B&O equipment, but your use case may be different. Thanks for the comment :-)
Hello, what the reference of the new amp op you place to replace the old? thnks,
They are Burr-Brown operational amplifiers (ICs) Off hand I'm not sure I wrote it down the model and I don't want to give away all the secrets of the kits. I believe there are forum posts about it though. Hope that helps.
Barcode is btw from factory. Mine had them as well. But only the glue of the sticker is left
Thank you so very much for this video. Currently at 3:39:47 mark and have been enjoying every second of it. I bought the kits from Martin, and even though the schematics that came with were really good, I was unsure on how to do for example the trim pots in his amp kit. No more. Finally I can get the rest of my penta project finished. I'm so grateful for this video. I've learned so much from your video so far, not just the repair part, but the science behind it to. Also I really appreciate you linking all of your equipment. A million thanks.
A small question I was wondering if you could answer. On my first teardown of the amp, I broke one of the "glass panels" that acts as a heatsink for the transistor. Do you have any suggestions on what I could use to replace it with?
Thanks again.
Hi Steinar Oen,
Thank you for the kind words and lovely message. It was great to read that first thing this morning! Thank you also for supporting me with the 'Buy me a coffee' link.
I've had a further look into this and feel silly for having left it out of the video, the large transistors are TO-264 style. If you google TO-264 insulator sheet you should find what you're looking for. However if you search for TO-247 insulator sheet, these seem to be more common and I 'think' are the same dimensions. Please check it against the size of your originals as I don't have mine to hand to check measurements.
If you need any further help please comment again, if you haven't already, please consider subscribing as I will be posting more B&O related content soon. Finally, I have various Beovision, Beocenter, Beosystem and Beolab speakers, I'm also considering doing videos on Datalink, Speakerlink and Powerlink in the future. Is there anything you would be interested in?
Thanks,
@@TheRetroBristolian Thank you so much for your reply Dave. Rest assured I have both liked the video and subscribed. I am very excited and looking forward to your future content.
This is great. I am currently looking into the insulator sheets, a million thanks. Thanks to you I now feel confident that I can breathe new life into my Pentas and I am beyond excited about it.
Did you have a hard time refitting the switches? I had a little hard time getting them back in place the first time I was inside the amp, and just yesterday I tried to switch the modes and one of them fell down into the amp, so I have to refit it again.
My Pentas no longer go into auto standby when it hasn't received any signal for a while. They used to before. I had them set to left/right, and tried changing to auto (how my switch fell into the amp) to see if they then would go into standby. It didn't help. What's worse is that when set to auto they, didn't even output anything at all. Do you have an idea why they no longer wanna go into standby automatically after a while?
Regarding the popping when they power on. I googled this "problem", and there seems to be a fix to it, but the google result sadly was an old forum post which did no longer contain the information on how to fix it. I am still looking for a way to get rid of that popping sound.
One thing that really piqued my interest when you were showing your awesome setup, was your subwoofer. Is this by any chance connected to your Pentas? If so, how did you connect it? I would love to see you talk more about it in future content - but if you wouldn't mind explaining it in a reply, I would really appreciate it.
Honestly I would be interested in any content with the B&O products you mentioned.
I am very new to the world of B&O, so I have very little knowledge about their products. For personal reasons I have always wanted a pair of the Beolab Penta, and while researching repairs online I have learned a little about their history, and would love to know more about the Beolab lineup.
To put it like this: I watched your video from start to end. You explain things detailed and clearly and you obviously have a passion and knowledge of what you're doing. I can't speak for others, but that captivates me at least. I would want more of all of that.
Once again, thank you so much for all of your help.
Take care and have a good one!
@@raz0r2k Sorry for the delayed response! You’ve asked quite a lot of questions there so let me try my best to respond.
In regard to the switches, YES! I would highly recommend not disassembling these front panels unless you absolutely must. For me I found have the panel casing flat on a table, tilt the lower edge up and place the switches into the casing, seat them in well and make sure it is at a steep enough angle they will stay put. Try and have them all at a central position and set the physical switches on the board to central positions. Have a friend adjust and shine a light down into the case/switch hat area. Now try and angle/lower the PCB down in. There will be a lot of trial and error and you will need just the right angle and amount of light to do it, but it is possible.
I had the opposite of the standby issue, one of my amps wouldn’t come out of standby, it turns out I didn’t connect the front door properly, so you have to make sure the ribbon is lined up with the connectors and all the pins match. For your issue however I think I have read about this, there is a relay on a small board next to the large capacitors under the transformer, that is the on/off relay I believe and sometimes they can stick. Have you looked at the service manuals? Do you hear the relay clicking on and off at plug in?
Regarding the power up pop through the speakers. I did a bit of a google recently myself and found the correct information. Essentially you need to add some additional circuitry to allow a small load to pass into the capacitors and charge them, this then stops the pop. You can simulate the effect of this by turning the speakers on for a few minutes, turn them off for half a minute and then turn them back on. You should notice no or a very minor noise. I may cover how to do this circuitry in the future in another video.
In regards to the Penta/BL2 (Sub) setup it all goes through the Avant 55, they are all connected separately via PowerLink to the TV. If you don’t have that sort of setup the BL2 does have Powerlink in and out and via the switches on the back of it you can set the crossover bass filter and route main sound to the Pentas by the output of the of the BL2. Hopefully this makes sense.
I’ll 100% be adding more content and covering more of the beolab lineup in repairs and reviews in the future.
Thanks again,
Hello, thank you for this wonderful vidéo.
I have a pair of penta 2 speakers, which have the same problem, when plugged in, it goes straight to yellow ???
I would always recommend doing the cap kits on these amplifiers, I did this first on my friends Penta1s and sadly one amp still went straight to yellow, that ended up being due to one of the large transistors failing. I talk about this here 2:52:33 it might be worth using a multimeter to test/check for shorts as I show. Let me know how you get on and good luck!
@@TheRetroBristolian Thanks, my friend
Best tutorial ever seen. Just wondering why you haven't used heatshrink tubes on the AC fuse wiring to support the soldered cables. You did it on the powercaps so why not here. AC wires (220V!) can break easily on those solder joints.
Hi Leslie, Thank you for the kind words, question and accidental phone call this afternoon!
You're absolutely right, using heatshrink on the AC wiring to the fuse holders would be a great additional to the guide/process. From memory I 'think' I did this on my second amp, but by the time I got to the end of this 5 Day plus recording session in a record UK heatwave I was getting a bit tired! I would absolutely say this is a worth while task.
It was great to talk on the phone and compare thoughts on various B&O topics. Perhaps at sometime in the future we could do a call/discussion on the channel? I look forward to making more content again soon and showing the Beolink 7000 panel you kindly sent over.
All the best.
Hello, great video. I just picked up a pair of beo lab Penta 2 they were working just fine until the right speaker stopped working. I just have the amber light and cannot play anything though it any longer.
What can I do to fix them? Thank you
Hi, if you are getting what B&O call the yellow light then the amplifier has activated its protection circuit. It will do this when it notices a fault. I saw this on a Penta 1 and it was down to the large transistors, my best advice is to follow the video and recap the amp as they all need that service usually now. but pay attention to my transistor checks section. with the bottom of the amp off you could use a simple multimeter in continuity mode and check for shorts across the 3 pins of each transistor - that was the fault on a Penta 1 as show in that section with the internally shorted transistor. Thanks for the comments and good luck
Thank you for sharing your knowledge and time!! I have a buzzing sound coming out of one of my pentas. I am low tech but willing to roll up my sleeves and learn. Can you give me some ideas on how to get started with troubleshooting? I have not yet gone through your video, so would appreciate your advice on how to go about it and if you can highlight the parts to pay special attention to. Thanks again.
Hey, Thanks for the kind words, It very much depends on the type of buzz and where it is coming from, it could be a loose connection, could be the particular input you are using. First think I would try (if it's only on one speaker) is switch the amps around, does the buzz follow the amp or the speaker? next is change which input you are using and maybe the device you are sending to the input. Again, you're looking to see what part the buzz follows. I did notice when I rebuilt my friends Penta 1s that before the rebuild there was a buzzing/crackling intermittently, the rebuild fixed this. Hopefully you can track the buzz down and see if an amp rebuild would be a good idea. Please do let me know how you get on. Many thanks, David
@@TheRetroBristolian Thank you for your response! I haven't had time to get to the speaker and will update here again after I try your suggestions.
Did this as well now. Total time each amp 4 hours to refplace everything
Hi. Just came across your vid. Excellent by the way. My penta 3,s have an issue. They both work and displays are on but when i turn them into standby mode one goes red and the other goes yellow. Have you any idea what the issue could be
The Penta 3 manual says:
The Beolab Penta is equipped with a protection circuit which is automatically activated if something is wrong, e.g.
- if the amplifier unit is
overheated,
- if a fault occurs in the amplifier
which could damage the loud- speaker units.
If the protection circuit is activated, the sound disappears and the light on the front of the amplifier turns yellow.
at 2:52:56 in the video I discuss about on my friends Penta 1s one was stuck in yellow protection circuit due to a shorted transistor, it sounds like yours isn't as faulty as his was, but if they haven't been serviced, doing a cap kit won't hurt, reflow of critical solder points to see if it improves the situation, I'm really sorry I don't have a 'smoking gun' answer for why your particular amp is doing this. Best of luck.
Thanks for your input 👍
Where i can see value of idle current and offset to adjust mine amps?
Time stamps are in the description 4:44:26 shows the adjustment of the trim pots
Hello, great video.
Do you provide any refurbishment services?
Thanks
Dan
Hi Dan, It would very much depend if you are local or plan to post the amps as that would be costly, also as you can see from the video it is many hours work to do. I would consider doing repair/refurbishment work sometimes, but sadly I am quite busy personally at the moment with one thing and another, is this not something you feel comfortable doing yourself? Thanks,
Great video! I'm currently trying to sort a problem with a Mk I amp.
Amp powers on fine, and switches green with signal. Issue is output starts at correct volume for a split second when switching on, then drops to a whisper?! You can just hear the sound.
I've checked the inputs (RCA and Speaker Link have the same issue), I've tested the PCB relay, and the main capacitors (which seem to have been replaced at some point), and all test OK.
Can you advise where else might be worth looking at for this issue?
It's a tricky one, As I say this isn't my day job. I wonder if changing the OP-AMP chip as shown in my video would make any difference. RCA would be my preferred connection for testing. have you checked the voltages as shown at the end of my video to make sure the amp is 'calibrated' OK? Also just check none of the caps are back to front/incorrect values. Keep us posted how you get on. thanks,
I just bought a pair of beolab penta and one of the speaker won't close the lid. Do you know how to fix it?
If you mean the front door won't lock into the latch shut and keeps sliding open, then that is covered at 56:29 you will need to replace the latch. If that isn't what you mean, please explain in more detail. Thanks for the comment.
Those doorlocks cost about 70 eurocent a piece. Some blokes on the net offer them for 10 euro each.
@@leslienelwanWHERE?!
@@TheRetroBristolian amazing thank you for your response - helped me as well.
@@Halarue Thanks for the kind words and dropping by, take care
Hi David. We have been left a B&O Beocentre system from late parents. Like many of your previous viewers we also would like to thank you for 5 hours plus of your time to help us all. We also have a speaker that is out of action. Can you please advise where I can source the appropriate fuses? Do you offer a repair service? Many thanks again. Stephen
Hi Stephen, Thank you for the kind comments and I'm sorry to hear about your late parents. All links for kits, fuses, parts used are in the video description if you expand it and scroll through. Although I didn't replace the 2A fuse so I don't believe there is a link for that.
I didn't do this video to self promote as a repair service, but I have had 4 or 5 people now ask this question! I would be willing to offer a repair service infrequently if it helps some people, but obviously my hope is to share knowledge and inspire others to perform successful repairs themselves.
I can be reached privately through RUclips@theretrobristolian.co.uk
If you would like to discuss options.
Thanks, David
Hi, I have a pair of speakers. bang olufsen model 6603 and I want to know how to connect a player, TV or amplifier since it only has red and black cable inputs on the bottom and only one RCA type input.
for the Penta 1 which you have you want to use the singular RCA inputs. on your TV or amp you might have left and right pre-outs or a headphone jack, you run from that to RCA jacks and just use the speakers as a left/right pair. on the little panel at the front of the amp you pop it open and move the switch to auto I believe. You should notice the amps turn on when they detect signal and will eventually turn off when the signal goes. I would highly advice you read the Penta 1 manual to become familiar with the speakers. always set your input to very low volume to start with as not to damage the speakers and become familiar with how they will work in your setup - thanks for the comment and dropping buy.
@@TheRetroBristolian These speakers are already amplified?... in such a way that if I connect them to an amplifier it could damage them... right?
@@TheRetroBristolian in the lower part it only has two holes to introduce a red and a black cable and it is only one RCA not two as they are normally used.
@@TheRetroBristolian hello, good afternoon, excuse the amplifier that comes with these speakers, can they be eliminated and use the speakers as passive and connect them to an amplifier?
@@enriquealvarez3157 Yes, if you remove the amplifiers following the steps shown in my video you can connect speaker wire straight to the screw terminals on the speakers directly to an external powered amp like an AVR etc. to reattach the base you will need some small bolts to replace the long spikes the amp slides over. Some people prefer them as Beovox passive speakers. I believe you do need quite a powerful amp for them to sound their best.
hi , only you can help me because you know the mk3s like the back of your hand, basically I sent the midrange panels to a specialized center to renew the suspensions, unfortunately when I removed them I didn't catalog the wires with the various colors, I was wondering if you could give me a hand. Greetings from Italy
This is brilliant. I am the original owner of a pair of Beolab Penta 1 speakers. They still work and sound great, even though I know the foam in the mid-range speakers becomes an issue eventually. My only issue is that one speaker is running hotter than the other. It hasn't triggered the yellow fault light yet but the outside case on the affected amplifier gets pretty hot with sustained use compared to the other speaker that just gets warm. Thoughts on the most likely cause of this issue and the potential fix? One enthusiast told me trim pot adjustment may due the trick. Other thoughts?
if the amps are working you can of course skip to the trim pot calibration part in my video and follow that. I would say (especially if Penta 1s), that a cap kit is going to be required. The caps used originally weren't all that great and are well past their use by date and could be slowly leaking/weeping like shown in my video. Take care and good luck!
I've the Mk2 model, but from one of them not heard nothing audio, but the Red light of amplificator is on. What is the problem? Should be one of 2 internal fuse burn? Who help me?
Hi again Dave.
I am unsure if you got a notification from my reply to your reply on my other post, so I'm writing to you again hopefully to get your attention.
I am very interested in knowing how you were able to connect your subwoofer to your Pentas, and would really appreciate any guidance on how to do this.
Take care.
I'll reply to your original comment. Sorry I've been crazy busy researching for upcoming videos.
Thumbs Up for the great detailed video.
I've recently purchased a penta mk 2 as well and the seller informed me he removed the amplifiers from the speakers due to one of them having imbalanced output volume. I have yet checked the amplifier on the issue. Will you be able to guess what could be the possible issue since you're more experienced on penta repair?
Also I'm actually considering getting my own capacitors to replace the old ones. In your video, on the powerpoint that showed the capacitor values, is there a mistake on the ones showing -10 +100%? As far as I know, usually its a + - 10% or + - 20% on capacitors. Please correct me if I'm wrong here.
Hi Keith,
Thanks for the comments and congrats on your Penta Mk2 purchase!
One of my friends Mk1s had muffled and distorted sound, the capacitor replacement brought it back to perfect clarity so simplistically I would guess its due the capacitors replacement.
I admire you wanting to source your own capacitors and no doubt its doable and there are some great brand capacitors out there, but I would like to explain/make one point. What we have here is a community of very passionate people that love their hobbies and love the B&O product line. Without people like Martin at the BeoParts-Shop I would have never had the confidence to attempt this repair. I'm a great believer in supporting the community, inspiring others, and giving back to those that helped me along the way. You are well within your rights to do as you see fit and use my video as you see appropriate, but I would ask you to consider a) the safety of Martin's kits and knowing they work brilliantly and b) supporting that community by supporting the people keeping it alive with new and exciting repair kits and upgrade kits.
When it comes to the capacitor values I've listed, I'll have to correct you if you're wrong I'm afraid! I totally agree it is a VERY odd tolerance to see and not something I've ever come across before doing this (but then I am relatively young/new to the process). I took all values straight from the B&O service manuals and on further research -10/+100% is known as the W tolerance. Further reading can be found on this site: www.iequalscdvdt.com/Markings_and_Codes.html
Thanks again for the comments and view, please consider subscribing as I'll be doing the crossovers and mid foam replacements later in the year.
@@TheRetroBristolian Hi, Dave. Thank you for the prompt reply on my queries.
I've visited Martin's website and added some of the kits to cart. Will definately support a fellow enthusiast. I'm just hoping to source for better capacitors as I'm not sure what capacitors martin are supplying (I'm quite a supporter on nichicon and Elna caps). 😅
Do hope to see more great videos from you soon.
Cheers man 😎👍
@@keithchua5840 Glad to hear it, good luck with your repairs!
@@TheRetroBristolian I've gotten the amp recap kit from martin via ebay. Changed the caps but my amp doesn't goes into green light(on mode). No voltage during the dc voltage trimpot check. Connecting to the speaker wire shows a -67mv...
Not sure if it's the faulty transistors 😫
@@keithchua5840 Hi, Sorry to hear this. OK so back to basics, did it go into green light mode BEFORE the work you did? Has it ever gone to a yellow light mode 'fault'? If it used to go green and now doesn't check the ribbon cables to the door are lined up with the pins on the board perfectly. When I did my second amplifier I accidentally got it one pin over and this stopped it turning on! Try toggling from off to auto on the door a few times, try leaving it unplugged, switch to auto and then plug in with it already on auto. You could also try attaching an audio source to it you don't mind breaking if there is something seriously wrong. My final thought is switch the doors between the amplifiers to confirm that there isn't a fault in the door circuitry.
In regard to the transistors, do the pin to pin continuity check across them all to see if there appears to be any shorts (as shown in the video) you could carefully desolder them and do the out of circuit checks also shown in the video before purchasing new ones.
Hope this helps
Hi David. İ have problem with my beolab penta 2 like in this video. Problem is the one speaker sounds more quietly than second one. Can u help me? What do u think it can be? Thank u! Like for this video.
Hey Ahmet, thanks for dropping by and leaving a comment. that sounds somewhat similar to a problem I had on my friends Penta 1s. It ended up being dried out caps that needed to be replaced, one speaker sounded muffled and distant where as the other (that I had just rebuilt) sounded present and really in the room with you again.
Just to rule out other issues first though, have you tried switching the cables between the good and the bad speaker? have you tried switching which output of your amplifier/input device you are using? Perhaps if you have a different device entirely, have you tried using RCA over Powerlink etc and toggling the switches? If you rule out cable and device issues and the problem still persists on the one speaker we can assume the speaker is faulty in some way. the next thing to do would be to switch the amps between the speakers (as in the bottom boxes) and see if the fault follows the amp or the speaker, from there you will know if the amp needs work or perhaps a speaker is blown or the crossover in the speaker needs work.
I hope this helps and good luck with your speakers in the future!
@@TheRetroBristolian i made everything what u wrote, change cables etc. i will check the caps that u change in this video. Because when i ON speaker after 2 days it works good and after few minutes it again start sounds quietly. By the way thank u again for your response. Take care.
Hi David. Me again) i change all caps, it works better, but now high frequency sound a little bit lower. I think it can be trimpots. Maybe u have some ideas about this problem? Sound comes like under the pillow😅 Not enough clear and saturated. Thank u very much!
@@axmetmeredov hummm I hear it's best to replace the trim pots, but you should with the amp off wipe them back and forth multiple times to clear any potential surface film off them and then resetup the amp following the steps I show towards the end of the video - did you make sure to set the trim pots? If the sound is still muffled did you switch the amps between the speakers to see if the problem follows the speaker or the amp? it is always possible the crossover in the speaker needs work or that the mids need refoaming perhaps. If I were you I would just want to make absolutely sure that the problem is with the amp and not something in the speaker. Let me know how you get on.
@@TheRetroBristolian yeah i already switch the amps, and this is not the speakers, also i calibrate the trim pots like u show on this video, but i don’t change them yet. When i calibrate a trim pots, the 30v works good and second one which 4v works incorrect when i calibrate it. I will change the trimpots and let u know. Can it be the opamp?
Cuanto vota el tranformador
Hi, I'm sorry I don't speak Spanish sadly and google translator says "When the transformer votes" - this doesn't really make sense to me? are you able to comment in English or try and translate to English? Thanks
I didn't understand that it was a commercial operation, too bad!
it's not a commercial thing for me, it's more that Beoparts-shop (Martin) has put time into making and selling the kits to the community, without his kits my video wouldn't exist so i'm just trying to be respectful of him and his business - hope that makes sense
Hehe capacitor 😊
My speaker very low sounds one tower only
Thanks for the comment. have you tried switching the speakers around? So connect the left cable to the right speaker and right speaker to the left? That way you can hopefully rule out the amplifier and cables IF the problem follows the speaker. once you have found your troublesome speaker you can then try some of the different inputs on it, toggle the switches in the amp back and forth a bit. If this doesn't help, now switch the amplifiers on the speakers around and see if the fault follows the actual speaker or the amplifier. if its the amplifier then it will need repair like I have shown in this video. Hope that helps.
a bit long - but very nice
Thanks for the comment! Agreed it does drag a bit, but hopefully you found the information useful :-)