1967 Marshall JMP-50 Model 1987 Plexi Lead Amplifier: Tube Rectified and Terrific !!
HTML-код
- Опубликовано: 31 мар 2019
- A super nice early Marshall JMP-50 Plexi amp showed up in the workshop......our very first experience with a Marshall amp.....and provided a great opportunity to thoroughly dissect it, compare its circuit to that of the Fender 5F6A Bassman, and then evaluate its tone through both a 3 x 15" speaker cabinet and a Leslie speaker. Viewers have been clamoring for a video featuring a Marshall amp......so here it is, and it's a DANDY !!!
If you enjoy advertising-free videos like this, please subscribe to our channel and consider becoming a Patreon patron at: / uncledougsvintageamps or making a PayPal donation to: dldcam@aol.com. You can also help by donating vintage tube equipment to become subjects for future videos. Thanks so much !!!
Here is a link to our Leslie video on RUclips: • Home Made Compact Lesl... 
Видеоклипы
Ollie is such a beautiful cat. That being said, I would give my left nut for a Marshall that clean. I was disappointed to see that someone had removed the original Mustard caps. FWIW the original JTM 45/Bluesbreaker amps were exact copies of the Bassman circuit and used KT-66 tubes. Those tube along with the Radiospares output transformers gave the early amps their unique tone. The tube rectifier tells me that this amp is a transition model right before they went to SS rectification. Another great vid, thanks Uncle Doug.
Thanks for your input, Robert & Tom :)
Great video again Doug. The amp really sounds great. The most remarkable feature of this amp is it's managed to survive for 52years without getting any white paint splatter on the top of it. Keep posting the video's, you put smiles on a lot of people's faces. Thank you.
You're welcome, Ima. Thanks so much. I guess British spiders wear diapers :)
Comments and Corrections: 1.) At 3:12 I meant to say built with "British" parts, not Fender parts. 2.) At 11:15 The transformers are all built by Drake and are correct and original for the amp. They are labeled with part numbers, not EIA numbers. 3.) At 13:30 This is one of the original Hunt's electrolytic caps, disconnected and left in place for appearance. 4.) The schematic used in the comparison is for a later model JMP (Model 2204), but it matches the demo amp fairly well. The correct schematic is for a model 1987. 5.) At 16:13 I meant to say trim "pot" not trim "cap".
Doug, love your videos man. I'm in the way straight to my first build but I have some troubles with the power transformer design and calculations. Can I ask you a few things? I need some advice and knowledge
Chris, have you watched the videos I've posted that deal specifically with that topic? They contain virtually all I know on the subject and are readily available. If you still need help, I can try to answer your questions here or on my FB page: Uncle Doug's Vintage Amps.
Yes Doug, and the series about that topic was as great as all the others. In fact, it's because of your videos that I feel encouraged to learn and try my first 5E1. But here is my doubt. I saw that some more actual amps like the Orange OR15, based on the Tiny Terror, have a way to reduce from 15W to 7W by taking the half voltage from the secondary of the power transformer. The well known original transformer for 5E1 is 325-0-325 and I want to know if I can make some sort of 325-180-0-180-325 for the selectable voltage to the rectifier tube and how to make it, what type of things must be considered. Also I want to add others changes to the original schematic such as gain pot, presence pot, shape (Orange style tone), and a 3 selector switch to ad by pass cap on both sides of ECC83 which is the only valve I've found at my local supplier
@@christiancosta7997 It's plausable to use a transformer with different voltages, although you'd need to be aware of possible bias changes. What you're describing is basically the same as "browning" the amp with a variac... cutting down all of its voltage a bit. Take a look at a schematic from the ORIGINAL Vox Night Train, not the G2. They used a Triode mode on the EL84s to cut volume. www.prowessamplifiers.com/schematics/Vox/Night_Train_Updated.html
Just saw this. I was thinking the same on the schematic. They had a JMP 50W 1987U model that had tremolo, from what I can see online. No idea what exact model number this is. Anyone know? The cool thing about this one is you can jumper those inputs and blend the two channels in parallel. Talk about overdrive!
I nearly teared up watching this, it reminds me of my old Marshall amp, that I traded-in in the 80's, stupidly. The biggest problem with them was 1) Don't loose the power cord!!!!! and 2) the selectors at the back could drop out during transport, everyone used to tape them up. Thanks Uncle Doug great video again.
I'm glad it brought back some fond memories, GK. The power cord problem is resolved, but we'll need to get some spare jumpers for the rear.
You are the best, Uncle Doug! Thumbs up. And that is one sweet vintage amp.
Wow.....thanks so much, Ken :)
Best 40 minutes I've spent in a while .. thanks, Doug.
You're welcome, Bob.
All of this was beautiful. Thank you Doug! Mike
The 50 watt Marshall's from this era are exquisite! Among the finest tube tones ever produced came through these amps! Beautiful specimen as well!
Thanks, Pat. I would tend to agree after this experience.
Another fantastic video for us ampoholics, Uncle Doug. That is one killer Marshall! Thank you for putting the time and effort into these videos. I'm sure it is not easy and very time consuming. I always look forward to your videos & appreciate them very much! Keep them coming!
You're welcome, Buddy. We will :)
Of course Jack and Ollie would start off with the Stray Car Strut. Thanks for a look into another great project, Doug.
You're welcome, GM :)
Super good vid, Uncle Doug. What a great channel to learn and enjoy your vast knowledge of electronics!! Keep em coming!!
Thanks, BU. We will :)
Amazing amp Doug! What a treat! Thank you and your trusting friend! KC is looking happy as a clam.
You're welcome, Han. My friend is quite impressed by all the comments on his amp.....and KC is the happiest little clam you could ever hope to see :)
I remember the days in dublin( in the 80s) that you pick up one of these things for 150bucks a pop, in fact i was walking by a music store one day and they were tidying the shop they had a skip outside (large waste disposal bin)and there on top was a marshall 50watt head in good condition for its age, i asked they guys why they were tossing the thing out and they said it had a blown transformer , needless to say it came home on the bus with me. replaced transformer and used it for 10 years then sold it for 1000bucks just when the vintage bullshit started ...true story Doug...PS love the posts
Wow!! Somebody's trash definitely can be someone else's treasure. Great find !!!
@@UncleDoug Persactly. I bought 2 of these in the mid-80s when nobody wanted old single-channel amps with no FX. Needless to say they're not for sale now. I love playing through them.
What a treat! Thank you for taking the time to do this and using the Tele. Now if you can find a vintage Hiwatt in as good condition. :))
Thanks, Andrew. A relative has one......but he lives in Chicago.
A vintage Hiwatt is a thing of true beauty when you get a look inside. It just might be worth a trip to Chicago!
Thank you for another outstanding and well presented explanation of the workings of these two amplifiers. Your channel never ceases to be a wealth of knowledge and understanding for us mere mortals who never could have aspired to this level of comprehension of this historic and beautiful old world technology. I hope the joy you have shared with us over the years is returned to you 10 fold.
You're quite welcome, Anthony. We sincerely appreciate your very kind words and wish you the very best.
I have spent the last 4 months watching Uncle Doug videos. They are amazing and his humour is my cup of tea!! Very informative and to the point. Hope there are lots more to come!!
Thanks so much, Richard. We intend to keep producing videos for as long as we're able......so stay tuned :)
That modern style mains connector is called IEC. That Leslie sounds delicious.
Thanks twice, OMM :)
Very nice, I especially enjoyed the component by component circuit comparison with detailed explanation. The cats are sounding tighter every time they play, I really enjoyed the opening song. Thanks for sharing.
You're welcome, Michael. The kitties send their regards, suggesting that you may be distant relatives :)
Yesss. I never expected you to go over a plexi. Yet, here we are. Thanks so much Uncle Doug.
You're welcome, Bryan :)
Thanks Uncle Doug for this very comprehensive review and curcuit comparison. I've learnt more about valve circuit design from you than any of the tutors I had when I did my trade 35 years ago. Your passion is obvious and appreciated!
You're quite welcome, Vinny :)
Ok I know you're not going to crank it, respecting the owner. Gorgeous vid, please say you want to build one!
I hadn't thought of it, John.....but it's an interesting suggestion.
@@UncleDoug go for it, and add that mojo your great expertise leads! It's gonna be awesome!
After your first successful Marshall build, if you want to start making a lot of money, I suggest you run a few well placed advertisements asking for trainees - people interested in building guitar amps. Hire 6 for starters. Then you train them and supervise the construction of new Marshall Clone amplifiers. Then offer them for sale. If you do this in a legal way I am sure you will absolutely end up with more money than you need. You might even be doing the world a service by introducing new guitar amplifiers under your personal brand name and hopefully at an affordable price. -Peter
P.S. Jim Marshall hired a tech right out of school (before he finished school) doubled his salary and had him have a go at making the kind of amp being asked for my the guitar payers visiting his shop. The technician is responsible for the modifications, Jim used his "ear" to say when it was right and "good enough". He sent a few of them out as pre-production units and people wanted to buy them after using them. The future was right there in the making and he went into production.Mr. Marshall did not do any design, lets be clear on that. The student tech is 100% responsible for all the electrical design modifications which were based upon Jim's blessing of the sound. So all in all Mr. Marshall actually was involved as it was he who knew what tone/sound was needed. The tech was clueless about music but he could solder, sketch out schematics and know a little bit about how to change the component values to achieve a change in tone.
I am not 100% sure of what I just wrote because I was not there! I read this here on RUclips a couple of years ago. It makes sense as why would a drummer ever have a need to modify a guitar amplifier components? Why did he hire a electric tech to do the work, if he could do it himself? The answer is he could not he needed the skills of a specialist, an electrical technician who was familiar with components that go into making a guitar amplifier. You "Uncle Dough" have that knowledge and I hope you take us up on the idea of building your own Marshall amp and then take me up on my suggestion to train a a small workforce and open up a small amplifier shop where you live. You have so many RUclips followers I think you already have a huge customer base. I know you are not interested in wealth. Your wealth is knowledge. But, I would love to purchase a Marshall type amp from you. Think about the future of all the young people who you provide training and employment. That might be a "Legacy" that you never considered. Maybe you could even start a tech school for building guitar amps. You could retire (again) and just watch it grow. Your knowledge of electronics will be shared and will flourish. That's another "Legacy". Uncle Doug's knowledge get's passed on and lives on!
Great Video, Uncle Doug and Jack, especially in explaining and comparing the circuits Fender vs. Marshall. It is known that Marshall-amps in the begining were similar to Fender, but now it could be seen in detail. This 1987 Plexi from 1967 you analysed, meets the origin. spec reg. the Drake-Transformers exactly. The trimpot is a useful feature to bias different brands of output-tubes, which really influence the tone. Owning the same amp, it was a great pleasure for me to get this Video. Thank you very much !
You're quite welcome, Klaus. Thanks so much for your very nice comments.
The best tube compliment I liked was Mullard EL84 and Ruby 12ax7. Wow what a fantastic sound in all of my 3 marshalls I used in 2006.
Thanks for sharing, Monty.
Nice demo,Great sounding set. That was very interesting about the difference between the two amps. Thanks
You're welcome, Hack.
Clapton used one in the Yardbirds, Jeff Beck prefers a 50 watt Marshsall of that design, and Peter Green used that same exact model to record The Supernatural.
Pat Nichols isn’t this also the amp of Al Di Meola’s heyday?
@@hubbsllc I don't know. Di Meola played a lot of different styles back then. Possibly.
In the 80s I was in a rock band where the lead guitarist had one of these (but ss rectifier), a '61 LP Junior and an MXR Distortion+ and the rhythm guitarist had a 100W SupaLead and an Explorer.
It was aural heaven, and complete carnage.
Sorry, didn't hear that last remark.
Me? Thunderbird into a DR103.
In England in the 80s they were giving these amps away (I bought a mint DR103 for £100 - it's still mint and worth a metric shitonne more now. Even got the bloody Bulgin plug/socket, a source of worry. If that lead goes missing at a gig...) .
Yes, but the tinnitus is worse in the left ear.
Since they were all 4 input amps you could jumper them all together. Speakers were 2x15 H&H, Hiwatt 4x12 (Fanes) 2 Marshall 4x12 and a Marshall 2x12, many of them original 25W speakers.
It was EPIC!
In fact epic did not do it justice. BIBLICAL.
Thursday? So am I, let's all have a cup of tea.
Yeah, just had to tell you.
p.s. the idiot guitarists sold all that gear (I nearly cried). I still enjoy mine.
Wow, thanks for all the very interesting info, guys :)
Oh my heavens, A "lay down" transformer plex with a tube rectifier. That is one rare and collectable / coveted amp. Marshall, Marshall, Marshall!
Amen, Ronald :)
Ronald Anderson mesa
Thanks' Uncle Doug!Really enjoyed this video!Had to replace
a H.V.Transformer in a later modal,with 6550s'!
Not the easiest thing that I have ever worked on!!! : )
Always a very thorough and informative presentation. Impressive UD. Thanks for the video!
You're welcome, FWR.
This video, maybe the first 5 minutes, made me spend like 6+ hours searching and discovering Marshall series and model name codes history, completely ignoring everything from lunch to whatnot. Now I can finally say I have some idea of where the series and units get their codenames and how they wrap in the evolution of different series. I can happily say that in the beginning it almost made sense, got very quickly out of hand and then around JCM900 it started making better sense once again. With little quirks that make it inconsistent.
They ended up mixing everything up with MR modern cabinet series where they could've used the existing codenaming to preserve some connection. Now everything is just 1960 or 1936. One of the things that has made the least sense was the 1922 vs 1936 cabinet. Same 2x12" cabinet, just slightly smaller dimensions in 1922.
But now it makes sense, 1959 (whatever series it was, JTM, JMP, JCM, reissues) was always 100 W 'Super Lead' head (first introduced when JTM100 came out), while 1987 was the same in 50 W, but only 'Lead' (except the first entry, JTM45 was naturally only 45 W). The main guitar heads of Marshall through the history. 2203 was the 100 W 'Master Volume Lead' and 2204 was the 50 W version of it (since JMP to JCM, essentially JCM were the same products, but in the 80's). Then there was also 2205 and 2210 which were 'Split Channel Reverbs' in 50 and 100 W (reversed this time, but you can see the code actually serving some function for once), which to my understanding were the first to include channel switching (FINALLY) and also reverb, happy days. There might have been changes throughout the different series (JTM, JMP, JCM) to those different Lead heads in sound and some might be more favourable than others (JTM45 being 5881->KT66, JTM50 series starting to phase out GZ34, JTM100 being solid state rectifier and going from KT66 to EL34. US distributor swapped from EL34 to 6550 in JMP series for busted tubes over transport and people thinking theirs 6550 amps sounded worse, but some liked the increased high frequencies).
It seems like the early JMP 18 W combos had EZ81 rectifier in 1965 (the prototypes of JMP series) and were replaced by 20 W models in 1967, which had solid state rectifiers. However, 1967 also being the year of transition from JTM to JMP and this amp being 1967 JMP, it's very possible that they were still using the last stock of GZ34 rectifiers in JTM 1987 models and this is a very, very early JMP 1987 model, very close to still being a JTM. A true collectible!
The first years of JMP series saw the plexi face plate disappear and be replaced with gold brushed aluminium. JCM800 series was born when Marshall finally got rid of the rough distributor deal, probably celebrating the beginning of 1980's as well, the amps being pretty much the same with new series name. The most consistent was probably the naming in JCM900 where you could read from the code which model it was, if it was a head or a combo, how powerful it was and the number of speakers if it was a combo. The nicest thing they did with product name codes was the T and V. If it had a T in the code, it had tremolo, and if a cabinet code had a V, it had Vintage 30 speakers. Obviously A and B also signifying the cabinet being slanted or straight as well. The worst they did in naming was having a solid state JMP 2205 called Slave, a 100 W PA Slave head. Other than that they held it together.
Wow.....thanks for all the info, Yuppi.
Great info. Thanks...
Jim marshal was a drummer he got a radio ham to desing his first amp they went and got a fender amp. At that time the only tranformers were ex military. Befor the 1960 we had ac dc 120 to 240 aftrer that the whole counry was rewierd to 240 vac than laterly we went to 230 to be inline with the eu. Here we have brown live blue newtral and yellow/green earth. Earth is a local earth to the property and neutral is earth at the substation transformer.
Thanks for the detailed info, Aj :)
Pretty ironic that the two greatest manufacturers of guitar amps weren't guitarists.
Thanks for sharing this Doug. It's amazing to see the differences between the two big amp companies. Great history lesson in amps!
You're welcome, PC :)
Thank you Uncle Doug ! It's time for me to come back in a new ''learning phase'' and follow you as before ! Happy to see that you're doing great !
You're welcome, Eric. Thanks !!!
Anytime you open a vintage Marshall you realize you are on hallowed ground.
Amen, Sting :)
Awesome!!
Jim Marshall had all his solder welds colored over with a red dye to basically distinguish factory from any mods or replacement work. It appears much was replaced over the years on this beautiful amp. Even the speaker solder joints were dyed red over the joint
I wondered what that red stuff was for.
Thant's an interesting bit of info, KV. Maybe I need to hunt down some red dye :)
Any working, gigged, 52-year-old amplifier is like Grandpa's hammer. Burned resistors, bulging caps etc., belong in a bin, not in an amplifier.
It's all about the integrity of the design really. Replace worn out components with similar quality parts, making sure you have installed them correctly, and there's no problem. Ultimately the thing has to sound good. Those famous Marshall players from the 60s and 70s wouuld have sanctioned any change to maintain or improve their tone. No point being precious about it.
Don’t quote me, but I think Marshall used nail polish on the solder joints. It served two purposes:
1. Protect the solder joint from oxidation.
2. So the Marshall repair department could see if any repairs or modifications were done.
I don’t think anyone has found the information yet on what the exact color and manufacturer of the polish.
Beautiful review, the Marshall and the Leslie are amazing rock machines, thanks!!!
Thanks so much, A56.
That was for me; a great lesson in schematic reading by comparison, if nothing else. I was also pleased to hear it being played at a level that gave the kind of breakup a consumer in '66-'67 would consider acceptable and not wide open as would later be the norm. Nice glassy highs and throaty growl from a beautifully made and cared for 'tele. Thanks for another great clip Uncle Doug!
Chris squire Bass player For YES played his Rickenbacker RM1999 (4001S) through a 100 watt Marshall for many years
Thanks for the input, Patrick.
I'm pretty sure that Duane Allman's amp of choice was a 50Watt Marshall Bass amp... at least that's what I'd always thought, but perhaps the story is that Duane played one of these- a Fender Bassman "copy"... Anybody know about that?
@@bradleysmith4409 There's some early pictures with a JTM 45 Plexi and the tall 4x12" cab but later on .. no idea
Thanks!@@zankyalbo2208
I'm bracing at the potential for April Fool's shenanigans, but something tells me this is the real deal!
I thought that the date of posting might arouse some suspicion......but in this case, the video is legit.
I was waiting for the Uncle Doug chainsaw :))
Hats off to Uncle Doug! Thanks a ton sir! Great work as always
Thanks, Luis.
So pleased to see you again with such a passionate and refreshing contribution.
Thanks, D.
@@UncleDoug Call your website 'Doug's your uncle', and all will be well.
I see scraped knuckles, which leads me to think some work on the 'rod has been taking place. How's it going?
I've had a really bad week. Drilled into my finger twice, cut it with a cutoff wheel (through my glove), burned on hot exhaust headers, pinched into a blood blister by a breaker bar (still numb at the tip), and my thumb knuckle cut to the bone on a nail head. Other than that.....things have been peachy :)
@@UncleDoug so sorry to hear about your woes, I've had weeks like that! Glad to see you're still chipper, though. You can't keep a good man down, even with self-inflicted hand injuries!
Uncle Doug, please don't hate me. I suggest you go talk to your doctor. I say that because I suffer from neck/head pain. Sometimes when the pain is more than I can handle what happens is my concentration becomes diminished and routine tasks become challenges and I make mistakes that I don't normally make.
I'm not saying pain cause those mishaps, I am suggesting something effected your concentration and you should look into it. If it's something your doctor can isolate end remedy then all is well right away. If it's an emotional or perhaps something is worrying you, that too can cause lapses in concentration. It could even be your diet or the time of day that you ate your meals.
When we are doing something we love to do we sometimes ignore eating/sleeping/resting properly because, well because that stuff is so mundane compared to our latest inspirational project.
-Peter
@@PeterDad60 Thanks so much for your concern, PD, but when you routinely do a hundred risky tasks in a day, every once in a while something goes wrong. I'm all healed up now and ready for more :)
That's a really noisy bypass cat.
The amp is cool too.
Cheers,
- Eddy
Thanks, Eddy. Yes, she really craves attention at the worst times :)
Uncle Doug has been practicing! I love you my friend.
It's mutual, Mr. B......but it really was Jack & Ollie :)
Very interesting and inspiring video! Thank you so much Uncle Doug and greetings from a '67 Marshall 1986 and '68 Marshall 1987 owner from Finland!
It was our pleasure, J. Thanks for watching and commenting :)
That assembly name might be Ioan (capital i), a Welsh variant of John.
Da iawn!
Thanks, B55. That would make sense.
In Greek, the name for John is Ioannis. ( who would have thought there might be a similarity between Greek and Welch?). Typically pronounced E-O -On-Yis although my uncles would sometimes call my dad, who was first generation greek-american, Yanni or Yannis. I'm not versed enough in Greek to know if that's normal or an approved way of saying the name John, or if they were just yanking my dad's chain, especially since he was the youngest. Dad didn't teach us any Greek, he wanted us to be fully American without any accent whatsoever, so that we wouldn't grow up to know the prejudice he experienced. My mother, on the other hand, being of French and french-canadian extraction, wanted us to learn French, and made us take lessons, but we rebelled, and none of us really did become conversational in it. I can read it well enough to get around in Canada or France without any problems at least.
Great video - this could be part of a tube amp design/repair curriculum. So cool to see the guts of an authentic, well-cared-for Plexi, accompanied by meaningful commentary.
Thanks, Jed. We're glad you enjoyed it.
What a fantastic specimen ! Thanks for the tour!
You're welcome, Rick :)
What a superbly entertaining video. Thank you very much indeed, and that Plexi is in fantastic condition. It's just a shame we can't all hear it in the flesh.
I agree, David. We'll all have to get together some day and have a massive jam session.......and beer & barbecue bash.
Wow! That rig is beautiful! Sounds amazing! Great stuff!
Glad you liked it, K.
Thanks for the great video. My dream amplifier! Very exciting also explains 👍
You're welcome, Meik.
You are a *wonderful* presenter! Thank you for your very enjoyable videos!
You're welcome, 4B. Thanks !!
Really is quite the orator
What a treat! Thanks for bringing us along.
Thanks for coming along, GG :)
Great video!! I have never fooled around with Marshall amps, so this is a great tutorial. Jack and Ollie really nailed the "British Sound" with that amp through your Kustom cabinet. Thanks again for a great video
You're welcome, Jim :)
Dear Uncle Doug. Thank you so much for your informative videos. I have learned a lot from you, and so have my Music Technology students. As for this lovely Marshall: Wind it up, Uncle Doug! That gain stage is a killer.
You're quite welcome, Neil. Thanks so much for the very nice comments. Regards to you and your students :)
Superb Uncle Doug, good and a compelling video !
Thanks, Steve.
Good day to you Uncle bob. This one was special for me. I am 54 and was a fender guy first. Swore off marshalls cause everyone else had them. Then it happened ......I plugged into a guys garage rig of 7 rows of full stacks with two heads on each one. A bit of a collector. Anyways that was it for me. Wasnt soon after that that i got a 68 baby box non export plexi. Its gone now but i replaced it with a metropoulos super lead plexi clone. Wow. I learned that billy squire lick early on and its a real pleasure to hear you do it. Thanks for the great insights. Loved the comparison of the two circuts. Now doesnt the bright fender input drop to 34k because of the switching jacks throwing 2 68s in parallel. This is something i would love to hear explained.
Thanks so much for your nice comments, Marc. Please watch my video on the Fender Input Circuit. It explains it all in detail.
This is like opening up the treasure chest! If you weren't great with amps, you have a voice for Radio! Enjoying this one.
Thanks, James :)
That old Marshall through the leslie was the most amazing tone just like Peter Framton in the 70s. Rock on Doug you rock.
Thanks, J. I too thought it was really unusual.....and nice :)
maestro Uncle Doug sharing his wisdom and rocking wicked game with the leslie!! Excellent video!!
Thanks, L14. Guilty as charged :)
I am blown away from your videos Uncle Doug, I must get back to my work and its hard...
Thanks, Amir. Once you have retired, as I have, you can spend all day working on projects of your own choosing. It's wonderful :)
Dropped the Lesley in right at the end! Nice touch, Unc!!!! Thank you for the guided tour through Marshall-Land....
You're welcome, Abe. I couldn't resist a little change of pace at the end.
Thank you, great video and nice to see such an old Marshall inside and out.
You're welcome, Erik.
so excited for this sam! watching it at work! couldn’t wait for home to see it.
We hope you really enjoy it, MH.
Thanks for the videos Uncle Doug! This is indeed a fine technological masterpiece, and you can call me funny - I just love those old ones you show us that have like a single 6SJ7 and a 6V6 and some kinda freaky art deco style cab with like cracking old snakeskin nogahide or something, those just make my day.
You're welcome, Ideal. By coincidence, I had planned to present an ancient little amp (exactly like the one you described) in my next video :)
Those are Siemens EL-34s. Back then National bought tubes from all over and just relabeled and sold them. I have a lifetime supply of them new in box. The only Mullards I owned were used, so it's an a fair test, but those are the best EL-34s I ever used and they last a long time. You can still find them for not too crazy money. They are worth it. Great for hi-fi and guitar. Great video!
Thanks for the nice comments and info, Sean.
~Uncle Doug~,electronics,cars and rock and roll,my kinda guy,thanks for sharing man!
The big three :) You're welcome, Ted.
As a happy Marshall owner, (A Superbass MkII - modded to Superlead specs), I really enjoyed your tour of the amp. THANKS!
You're welcome, Ray :)
Great video Doug. Many thanks.
You're welcome, SS. Thanks !!
I own a 1970 JMP 50 watt head that I purchased new in 1970! It was my first serious amp, and I paid $595 for it with the 8x10 speaker cabinet which I sold just a few years later. It is in ‘near-museum’ condition and at first glance looks identical to this beauty. Mine, however, has an aluminum front panel and solid state rectifier, which is actually my preference sonically. I have replaced all electrolytics and set bias each time I’ve replaced power tubes, aiming for a just slightly warm 38mA. I’m not worried about using EL34s as I’ve replaced them several times. I’ve even kept the original Mullard EL34s but one is shot.
What’s really important is, it sounds glorious! I have recently decided to never sell it. The tolex is in even better shape than this beautiful plexi’s. I will use it until I die. It’s going in my will to my daughter. She doesn’t play, but maybe it will buy her a car one day.
It sounds like a wonderful amp, Peter. I don't blame you for keeping it.
Uncle Doug Thanks Doug. Sorry for coopting your comments section. I felt like I was looking at a twin, couldn’t help it. I really enjoy your videos and would like to have contact info to recommend you to customers. I only work on my own stuff but from what I’ve seen, I would send anyone to you. I don’t know how to pm someone on RUclips. Any ideas?
I'm real selective on what I work on, Peter. It would have to be a vintage tube amp, the older the better. If a customer wants more info, they can contact me here or on my FB page, Uncle Doug's Vintage Amps.
Uncle Doug But of course, selective, I picked up on that right away. Thanks for the info. Most of my customers are very choosy, and I would just refer them to you directly. I’m sorry I’m not on FB, but you can check me at www.artisanmobile.com if you’re interested.
Really nice video .... informative & entertaining to watch, esp. for me, who knows very little about how these amps do what they do. One thing that would have been nice during the demo section would have been to jumper the two channels with a patch cable, the way that most players used this amp back in the day. This makes both volumes available simultaneously, and since the two channels are voiced a bit differently, one can come up with the classic thick JMP sounds that we all love.
Thanks for a well thought out and orchestrated video.
You're welcome, Andrew. Thanks for the suggestion.
Great Vid Uncle Doug!! Man I love Marshall's!!! I was diggin' on your playing and song choice at the end too!! Sounds RAD!! Cheers!!
Thanks, T73 :)
Did you riff on "Something in the Air"?...I totally heard that in there!! Cheers,@@UncleDoug
He is the best and always delivers a great video, love the channel keep em coming.
Thanks, David :)
Gobs and Gobs of praise for bringing to us this magnificent item of the 1960's (EW).
You're welcome, EW.
Had a 50 watt plexi back in day....brings back fond memories....thanks Doug..love yr videos...Casey the 🐱....was giving you his banter in background .....😸
You're welcome, Glenn.
Fantastic, been waiting for a Marshall video, cheers from Brazil!!!
We hope you enjoy the video, MlF :)
Ahh, love the Marshall Plexi examination. Don't get to see inside one of those often. Also digging' the scenery & the desert welcoming spring w/wildflowers & cacti in bloom. Thanks, U.D. !
You're welcome, Jerry :)
Great video. This amp bleeds classic tone. I would have liked to have heard some dirty tones (that's only my personal preference though). Thank you Doug and thanks to the gentlemen who let you use this great specimen. Your videos will be learning tools for years to come.
You're quite welcome, Chuck. Thanks for your very nice comments.
What a great amp video, nice work Uncle Doug. There is a fellow close to me here in Florida that an absolute expert on Marshal amps and I’ve have the opportunity to sit in on a lot of repairs and learned a lot about these amps. They are really wonderful. This was a really nice video of a great amplifier, thank you! Buddy
By the way, I had to add how much I love your Custom padded cabinet!!! Custom amps were everywhere when I was young and one day I’m going to find one for my own collection.
You're welcome, Buddy. Thanks for your very nice comments.
I had that same amp back in the day. Wish I had appreciated it more at the time.
Yeah, I know Mark, I'm into them now. God Bless Uncle Doug! He's the best!
Wow, thanks so much, TG.
Wow, the tone with the leslie unit was really amazing, very "deep" sound!!!
Thanks, Sebastian. I posted a video showing how to build your own.
My time watching one of your videos. Great content and easy to understand for a noob like me. Really appreciated the play through at the end.
Greetings, CK, and welcome to our channel. I hope to see you here more often :) Thanks !!!
Awesome AMP ! Thanks for Your Help and Time !
My pleasure, Andre.
WOW!! What an amazing Telecaster!! My 2001 or so model Tele with Seymour Duncan pickups is hiding in the corner as we speak!! I have really enjoyed this exploration of the Marshall Plexi Amp!! so cool! I never really understood what a plexi was until now! Thanks for all you do for us!! I just noticed that this cab is just like the one that a friend of mine back in the early eighties had a Kustom cab just like this, he was really into southern rock like Allman bros band and the like, He played lead and was very very good. I was learning from him until he moved off for work. It was a sad day for me, lol. Thank you for all you do Uncle Doug!!
You're welcome, Jack. Thanks for watching and for all your very nice comments.
Great rundown Doug! I have been waiting for this for a long time. I would love to have a plexi but I would prefer to eat and have a home lol Great vids as always!
Thanks, Mike. Me too :)
Just found your channel. Love your pets and great informative videos. Thanks a ton and keep doing what you're doing. Earned another subscribe (:
Welcome aboard, Aaron. Thanks for subscribing !!
Thanks Doug! Very nice lesson!
You're welcome, Robert.
Man what’s gonna happen when guys like Doug leave us ? I’ve always been to impatient to study electronics took a vocational course back in 1979 and thought I’d loose my mind on the constant upgrades and knowledge on the subject but will say that Doug makes it very easy to understand and he truly is a master at it 👍
Wow, thanks so much, Doug. We plan on being around for a while yet, so don't start worrying prematurely :)
Great video Uncle Doug
Thanks, Gary :)
Some of the best content on you tube.... those of us who sub uncle doug know it all too well . We love ya uncle Doug . I've never met you but I have no doubt you are a good man and neighbor
And damn what a sweet amp
Thanks so much , IA :)
I came just to hear Uncle Doug play a plexi! Didn't know I was gonna get to hear you play it through a Leslie too. way cool 😎
We aim to please, Jon :)
Nice one Uncle Doug, you certainly know how to make someone feel amp envy, then you bring out the fender, SHEESH, your making it hard you know. Thanks for a great video, as usual.
You're welcome, Zing :)
Really enjoyed that Uncle Doug. Greetings from York in England. The original York ;-))
That's great to hear, YK. Salutations from the Sunny Southwest, USA......otherwise known as "The Colonies" :)
If we can get Uncle Doug to stop by D-Lab to show them how to PLAY we’ll be all set! That was really nice to hear!
Thanks for the nice suggestion, G. Ollie and Jack are available.....but their contract has many provisions, including fresh catnip and ear scratching ;)
I bought one these in Germany with a 2x12 cab for 450 Deutsche marks in 1988 (about £150 at the time) sold the cab for £50 and took the amp back home. Mine was a 1970 (inspection certificate inside had the date) ....I had a smug look on my face when I sold it for £350 in 1996.....needless to say my smugness has matured into a self loathing.....not so much for whats it's now worth but for the fact that it's a work of art that I got rid of.. A piece of Rock 'n Roll history!.......Great video Uncle Doug!
Beautiful tones from a beautiful amp....A well-maintained Plexi is becoming a very rare bird! Beautiful shots of the West Texas desert, too! 🌵🎸☑️
Thanks so much, Mike :)
Nice sounding amp for sure, and the playing isn't too bad either. Your turning into quite the rocker. I remember bands playing back in my high school days using the Leslie cabinets.
Thanks, John.......glad you enjoyed it.
Very cool 😎 I wish you were my uncle, Doug. I always learn something worth knowing. Pats to the cats. 🐈🐈🐈🐈🐈
Thanks, 08 :)
I bought a small box 50, 1987 metal panel with a blown p.t. in the mid 80s for real cheap. I replaced the faulty P.T. I did a gig with it and the sound man came up at the end of the nite and said "That amp sounds great." He didn't say the band did or I did but the amp did. I'll take it.Uncle D, I love your 427 with a two barrel carb. My old bass player had a 65 442 with a LS6 454 Corvette engine that he bought new in a crate because his uncle worked at a Chevy dealer. I can smell the exhaust now. Hot rod cars, Hot rod guitars and Hot rod amps,Yea Man. You wanna hear some of the best L.P./Marshall tone? Duane Allmanns solo on Eat A Peach,Mountain Jam sol after the drum and bass solo. He gets every shade of tone from clean to infinite sustain,Don 't get me started.
Thanks for all the nice comments and reminiscences, Halbert.
Wow! That was thoroughly enjoyable!
That's good to hear, James.