IT'S BAAAAACK! Marshall DSL100 Motherboard Replacement
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- Опубликовано: 19 май 2018
- Part 2: • Tracking Tube Amp Nois...
This Marshall JCM2000 DSL-100 Dual Super Lead head came back after all. You may recall in another video I did some work on the motherboard. The customer had been blowing fuses and he replaced tubes and it still blew fuses. The problem seemed resolved after my work was done, but nope! This time we go for the nuclear option - replacing the motherboard. You can see the original video here: • Mother of All Marshall...
This same customer also brought me a malfunctioning TSL100 head this time to also go ahead and have the motherboard replaced to the most up to date version and also troubleshoot whatever else might be wrong with it. That will be the subject of another video.
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Part 2 is here: ruclips.net/video/PaZU37iadXg/видео.html&index=11
The Guitologist Orange amps makes a tube tester for all kinds of tubes.
Dude. You HAVE to have a good quality tube tester to even start servicing tube gear. WTF? The VERY first thing I do is test tubes with two different testers that are really good at certain tests. I most often need to replace one or more tubes to even begin. One tester has a great short test and the other is great for matching tubes. A Sencore Mighty Mite 4 and a B&K 700/707 Dyna Jet. Now get with it and save yourself hours of chasing your tail when a bad tube is the problem to begin with. Shit post Monday...
Out of stock - maybe there is a generic 100W board out there? Something with 8 tubes
you all prolly dont care but does someone know of a trick to log back into an instagram account?
I stupidly lost my password. I love any tips you can offer me.
@Beckham Otis instablaster =)
Thank you very much! I bought a TSL 100 off Reverb that had HORRIBLE bias drift. I watched your video, ordered a new board from amplifiedparts.com and swapped it out myself. (Thanks to this video) I set the bias and watched for about 40 minutes and there was very little fluctuation at all. I couldn’t have done it without you!!
I watched all of Brad's JCM 2000 DSL videos with great empathy. I have a 50 and a 100 watt - both worked fine but a few years ago, after much research, I decided to fix what wasn't (yet) broken on my DSL50 - a 1998 model. There is FAR too much data out there to go into here - just suffice to say I pulled the main board, taking pics and labeling all connections, and ended up making about 33 component replacements/modifications (Joey mods). I also installed a choke. I was more than a little shocked (sorry) when I turned it on and it worked perfectly and sounded better IMHO. I'm going to do the 100 next. I ordered a new main board from Marshall - probably a year ago - but haven't had the time/patience to dive in. But it is coming up. There are discrepancies between what is physically on the early boards and what the later issue schematics show SHOULD be there. There is/was discussion on the forums that Marshall screwed up and/or the early boards were substandard etc. Don't know. There are also issues with the speaker jack grounding. Mine work - modified or not but I don't gig hard with them either. Unless you are a gambler, I would just buy the latest DSL. They review well. Some of us, however, are completely deranged and like to tinker. I like the old ones when they are done right.
Former Marshall dealer here. About a third of their products didn't work out of the box, so we had to unbox everything and test it before sale, then ship back at our expense. And damn near nothing was easily servicable. Hated them. They're still riding the wave they created in the 70s; nothing else would explain the sales they still get today. Nothing like needing to replace a damn motherboard because you jerked on the guitar cord.
You deserve a medal just for going through all the plug connections... thanks :)
I am amazed at how the entire board (example: the tube holders) has been cheapened over the years. Great video as always.
Yay, a new video, Sunday Night! You totally rock Brad!
Thanks for watching, as always, buddy.
Brad I have to say, I have learned SO MUCH watching these videos! Been able to help friends diagnose problems and get them fixed. Keep these vids coming!! Great stuff! Thanks!!
Also! The increase in production value lately is really cool. Thanks for that as well. It has definitely been noticed and appreciated !
Thanks for watching and taking time to comment. I appreciate you.
This is exactly what I needed to see! Same problems with my DSL. Thanks Brad! This helps a lot
DSL'S have come a long ways. I just got the DSL100HR and it's just a great sounding amp, with great upgrades including external bias points and a better eq. It's not a handwired amp so those board problems will be there down the line but I truly believe even the boards have been greatly improved.
I wish I had known about the bias drift issues with these before I sunk a crapload of $$ into mine before selling it off for parts. If only your vids on this were around 13yrs ago... :)
I know nothing about what you are doing but I enjoy watching anyway. not to be confused with any other context where the words "I like to watch" are said.
Awesome a new video thanks for sharing your knowledge with us ive learnt a ton from you, and the upgraded equipment is awesome thank you for everything brad.
I like how even after you told us you had a Dual and a Triple board, you still stuck the wrong one in. That was good for a chuckle man. Thanks! I do dumb shit like that too but, it's always funnier when somebody else does it.
The two boards have the exact same screen print number. Only the sticker is different. Dumb mistake.
Hey Brad. Thought you'd like to know I just worked on one of these "Issue 20" boards from a JCM 2000 DSL 100. Blew up like the older boards with a runaway bias. So the new board does not solve the problem. I ended up taking a Dremel tool and removing all traces leading to Pin 5 grid through the 5k6 resistor. The bias circuit leads back to connector 12 (which has no connector installed) and the 2 outer pins are the bias feeds to the tubes, one per pair of tubes. Each feed also ties to the feed for the little bias adjustment board. I just wired it straight with wire and the 5k6 resistor off board, after removing the traces and replacing the resistors and 2 caps for the bias and good to go. Those boards become resistive on the bias circuit after prolonged use and heat. You saw on yours the bias kept creeping up. It's the crap material and placing it right next to the plate voltage. There is also a kit from Dr. Tube or something like that that basically drills out pin 5 from the board, achieving the same removal from circuit.
Exactly ! !
I have a dsl 100 I bought new in 1999. Toured regionally and used it 4 nights a week for many years. The tone was incredible. I replaced the el34’s about every 6-8 months. Once I replaced them and apparently got a bad quad and they went up in smoke. Replaced them again and things were ok for awhile but then started having intermittent issues with the volume completely dropping off. All tubes including preamp were working but no volume. You could hit the amp(Fonzie style) and it would start working again. I thought this seemed like a cold solder joint so I replaced all tube sockets, resoldered all connections in the entire amp. Thought I had it fixed but a couple of shows later, the volume would completely drop again. I worked with this thing for weeks and finally had to get another amp. Still have the dsl to this day but it still has the same issue from years ago. Frustrating because I really loved the tone from the old ones compared to any newer dsl. I think these amps were engineered wrong from day one and the components can’t handle the currents these amps push. I just wish hard-wired was still a thing. So much easier to repair.
Yeah I agree the standoffs were very annoying, but on the brighter side the music during the board removal and reattaching was lovely 😊! Made my day
Jeez all I can ever think of is how someone actually came up with all of this...
All the small electronics and the whole circuit, what order they need to go in, that it even WORKS at all...
pretty fascinating sometimes!
Hey I just did my tsl 100 yesterday. Was a pita. I screwed the tube sockets back on, then realized I didnt pop off the annoying $2 standoffs off of the old board , you had me rolling when you said the dam bean counter. Lol
The elevator music is taking me back to being rolled around in a shopping cart at Kroger in the early 80's. 🤣
It takes me back to when they had tube checkers in the back corner of the drug store
So incredibly excited I can't wait to see part 2
Part 3 coming soon! I will not be getting one of these amps.
Brand new board and it comes with bent resistors. Also love the bodge capacitor on a latest revision board.
What I did with my tsl was put a sticky label on each connector and write on it where it came from and
The new board worked straight away , I biased at 75ma?. before I changed it I had the two valves cold thing, and one red plating.
Anyway she's ok now
Love your videos.
oh Brad, I just love the work you do, even though I know noting about servicing amplifiers, I just LOVE the work you do. not to mention that fancy finger pickin' on that Tele of yours...
Great video and keep posting! Thanks!
Thanks for sharing with us!
Hey Brad, thanks for posting your vids, it's always great to watch someone else go though the process and learn. But after watching a couple of your vid's where it would it seems it would be a great help, I have to ask why you don't have and use a tube tester? On the DSL and Epiphone vids especially it seems like testing the tubes right off the bat would have saved a lot of time. Any time I have crackle, popping, or a resistor failure on a power board I test the tubes right out of the gate. And if you get a short like the EL-34 demonstrated on the DSL, odds are you're going to be dealing with a bad tube. It's saved me tons of time and shortened my troubleshooting process significantly to test the tubes. I have also more than once had a brand new tube fail right out of the box, so swapping them isn't always the most direct rout. Thanks again for posting, keep up the good work!
Brad, the Bossa Nova elevator segue music is a riot... and BTW,
all my sympathies and cheers
It’s sad you got caught in the trap with these amps. I have repaired countless of these bias creep wonders. I was lead to believe Marshall changed the type of PCB material in 2003. Between 1999 and 2003 the tube main board was hydroscopic. Issues of HV tracking around the control grid caused bias creep as the board started to breakdown when hot. (Yes I know about the 220k grid stoppers) I stripped a board down and conducted a insulation test at 500 volts and 1000 volts. The results were jaw dropping. A early fix was to drill out the control grid on each power tube and the. Point to point wire the complete section back to the driver tube. The other day I had a 2004 model come in with a revision 6 board. I was of the understanding the from 2003 this tracking issue was fixed. In this case it was the worst I have had. I did the point to point mod, and fixed the bias issue, but found myself dealing with a hum issue where we had leakage between the HV and the heaters on the driver tube.
I have now learnt the clean channel on the TSL which use the same type of PCB has a hum issue on the clean channel. My advise to any tech
Is to replace the main pcb with the latest revision for a TSL or a DSL I have lost so much money on these amps. And like you have worn the cost of these long repairs which out way the value of the amp. Replace the board with a new one, yes very expensive repair but the repair heartache won’t be there. I personally owned two of these amps, and both developed the issue.
Like the sound hate the amp.
I remember the devil board in the Sylvania super chassis when I worked as a TV repairman at Montgomery Ward. The combo of solid state and tube can be a nightmare repair
Brad, between your videos and uncle dougs I’ve learned so much about amp repair and tube amp theory, your videos are a godsend! Thanks for your efforts in recording and putting them up, let’s keep the art alive !
I had one of these when I was in the pro business. Great amps (used by my hero Gary Moore) Stick a treble booster in front of it and it has a phenomenal sound!
way over my head.dont know why i watch. but i enjoy. thanks.
I know this is pretty old now, but quite a few years back I rebuilt a JCM-2000 DSL100 had never been worked on, but had issues, the board was a later rev without the conductivity issues that some have/had, but going by the revision schematic component values were all over the place and where there SHOULD have been 1/2 W resistors were 1/8 W and improper values... and where there should have been 1 W were 1/4 W... lots of this... and there was an open in the Bias circuit, and bias was cold but could not be adjusted, the trace was non conductive on the board... path repair later and it was up and working. I still have it and still use it. Regularly they are great amps with a couple component changes too, I had to end up replacing the Mains and output Transformers as well for different reasons but it never blew fuses.
1st step in tube troubleshooting: Test the tubes!!! A good tube tester should be your most important piece of test equipment on your bench. I could have saved myself so much time and headaches had I learned that when I started. Now it is the first thing I check after the fuse and a visual inspection.
Tube testers are often worthless when problems only happen intermittently anyway, as seemed to be the case with this amp initially. An amp is a tube tester. A tester would not have caught the issue with these tubes. It's very rare I've been helped by a tube tester. Put it this way...if I tested tubes as a matter of course every single time I had an amp on the bench, I'd have a lot of wasted time under my belt. Tubes are rarely the issue in the older amps I normally troubleshoot. I might start testing up front on Marshalls though! These amps seem to EAT tubes. Thanks for the comment.
To each his own I guess, although I don't know how you come to your conclusions after admitting that you don't have a tube tester that will test the power tubes. Get a good tube tester, you will thank yourself, believe me. There are five essential tools to be an efficient amp tech: O-scope, signal generator, tube tester, a good soldering station and a good multi-meter with ESR function. Everything else are nice-to-haves, but these are the essentials IMO. Keep the amps alive brother.
WILLIAM LAND
No oscilloscope, no tube tester... First things I purchased after multi meter and signal gen 50 years ago. Today you can buy a scope for $500 that will rival what took 18,000 or more in the early 70s.
That was the point I was trying to make. I tried to use a little more tact though. Be careful, or you will end up on Shit Post Friday. LOL
Electrofrying D: You know, the guy is honest, he doesn't edit his video to show him as a superman of the repair, he's super nice. He's on a learning curve like all of us.
Who is super efficient and doesn't make any error ?
If you do, then go ahead and throw the first stone, like you just did ... Or Cut him some slack, my friend.
Good piece of music to help the monotony of that irksome task, but I bet you generally enjoy it. Good job and hopefully for good sounds.
Fun Sunday night of tube amp know how. Thanks Brad \m/
What are your thoughts on Molex connectors in guitar amps? Affect tone? Longevity? Any real effect?
I like how you assume later revisions are an improvement and not just 'cheaper'. :)
Find and Buy a Marshall MG 100FX.Got mine in 2009 its now 9 years old and not one single issue i haven't used a Tube Amp of any kind since 2009..and most likely wont Solid State/Modeling Amps are for me..Great video Brad
Considering how iffy these are, maybe not a bad idea.
And will still sound like a bag of shit, sorry these Solid state Marshalls are junk tone wise.
Frank Quinn to who? you your opinion is your opinion means NOTHING to me or Many others who love the Marshall MG 100Fx and other Solid State - Modeling. Amps Tube Amps are not reliable or all that versatile..the Solid State - Modeling Amps most certainly Are i also stopped using Tube Amps in 2012 haven't used a Tube Amp since Solid State - Modeling Amps do everything a Tube Amp does and much much more and much more reliable
@@johnnyvanbrock2374 More versatile? Ok. More reliable? Let's see in 50 years if that chip-laden POS is still serviceable. Sound better? It emulates real tubes quite well but does not have all the magic and feel. One day you'll play on a real amp again, and you will probably realize what you've been missing
I’m not sold on the modeling amps. I want to try the Marshall, but the ones I’ve played so far (about every other one made) sound fake. They sound throttled. Theirs no sweeter a sound than a properly dialed in tube amp.
Correct me if I'm wrong (and I probably am since my knowledge of electronics is minimal) but to me it looks like the main board in these Marshalls are effectively power amps with the pre-amps on seperate boards. To me this makes sense because in terms of the component layout both main boards were very close to each other.
My effects loop and reverb is dead on my 2009 JCM2000 DSL100. Any suggestions for me to troubleshoot? I ran a cable from the send to the return. Nothing but loud noise. No guitar signal. The amp works, all channels are working. The Deep Switch and the Mid switch. All works. No effects and no reverb.
found this channel about a week ago can't stop watching, but I notice you haven't done any musicman amps are they that good, only saying mine needs servicing and I'd like to see just what I need to do, great channel
Have you had a Marshall jcm 2000 that the reverb goes in and out of on the clean channel?
Hi! Did you have problems with the equalization and the deep button after replacing the valve board?
I broke a tube, replaced all of them, rebiased it, then one of the resistors (5W1KJ) blew apart and knocked a capacitor off at the same time. Soldered the capacitor back in and waiting on a resistor now... but may end up having to replace the board if it doesnt work.. Its an early model. What are the problems and symptoms of the early boards I read about going bad?
Hi Iam curious how do you drain the capacitor for this type of amp? is it enough to drain on the diode?
For taking off those standoffs I think I remember pulling the ink cartridge out of a bic pen and the hole was just right for compressing the tabs to slip them out. That usually made them easier to put back in because there wouldn't be any ridges from plyers to press through.
I've had to replace the main board on dozens of these. Very slightly conductive material causes bias drift. I spent a full day on my first one, eliminating everything. I simply couldn't believe the actual board material could be bad!
How do you know Brad was in I.T.? He calls an amp circuit a mother board LOL. Great video man, as always!
So all this fancy circuit board manufacturing is better than point to point wiring for guitar amps. How do you keep track of all the connectors between boards? And those transformers are fkn huge.....Thanks Brad, you rock!!
Hi Brad - Interesting video. Thanks for posting. I have a couple brief questions: What year was that DSL-100 amp manufactured? Those manufactured after 2003 supposedly don’t have the runaway bias issue (mine works wonderful). Also, did you elect to keep the amp’s bias in the mid 60s mV (and not the specification of 95 mV) since you felt it would drift otherwise?
I read people advocating bias in the high 30's to mid 40's for these .. !
Hi, really like your channel! Do you have any suggestion on tube power amps housed in a 2u case?
I have/had the TSL and really liked it when it worked. It went into the shop several times and still had issues. Took it to another shop and the said the board was bad and that it was a common problem. If only we'd had internet reviews back then like we do now! Right now it's a door stop but every now and then I think about replacing the board...
I have a couple upcoming videos you'll want to see.
I'll be looking for them!
Or sell it to me for a fair price, I love working on Marshall amps!
what song/artist was playing in the background during the time when you were removing the tubes???
It's called "Ipanema Dream". Found it in the copyright free RUclips library.
Any recommendations on where to purchase a new motherboard now that it is 2021?
Antique Electronic Supply
They (Marshall) fixed the wandering bias issue in 2006. When I got my 2nd (an '06) I bought used in 2014 the bias was set at 124mA! adjusted down to 84mA and have had no problems.
It would be nice to know what actually fails and causes the
whole thing to pop. It could be as simple as the heavy elevated power resistors inducing a fine crack in the PC trace under it. Same with tube socket, anything that gets really hot. Solder mask hides a lot of foil trace failures.
it is caused by defective pcb material. Over time the heat at the tube socket causes the board to conduct current from the bias pin to the adjacent B+. Replacing the pcb is unnecessary. Drilling out the bias pin and wiring the resistor direct to the tube socket resolves this issue and saves lots of $.
You just pull those plugs willy nilly! Haha... glad you know what your doing cuz I don't! You are INSANE! I Love ALLADIN SANE! Oh wow! a board swap! I now kind of understand biasing tubes! Thanks Brad!
I had one of these. One of the earlier ones. Big problems. Tech had to do what he called 'lifting the traces'. PCB is a dodgy design in the old ones. New ones are said to be fine. I wanted to rip the guts out and put a turret board in, but ditched and got a JCM 800
Been watching your videos quite sometime now, question- did you have to go through some schooling to work on these amps? Self taught? Back in 2005, when I had plenty of time, I bought an 3 inch book on electric guitar modification, tune-ups, and repair and have been very fortunate on having a small group of customers bringing me their guitars to work on.
Brad, I need the same board. where did you get it. I think if I got a board I could follow your video to replace it. Your always informative and sharing.Thanks!
Antique Electronic Supply: www.tubesandmore.com/products/board-marshall-replacement-dsl100
Takes about a month for them to restock when they're out. Order it and they'll send when it comes in.
james manhart also hotrox UK sell them I don't know how expensive it Will work out coming straight from the UK maybe cheaper??
I fitted one to my tsl it's like a new amp now
You can also buy them from Marshall direct, the factory is just over half an hour away from me.
You can probably buy the one in the video from the amps owner.
www.hotroxuk.com/ This place is less expensive than tubes and more, plus it is faster. You don't have to pay VAT so when you see the price don't worry.
I watched the first video yesterday and, even though I'm a few years late, I knew that amp was going to be back. Had to have my board replaced too after 17 years. Great amps other than that damn faulty board. The newest boards are great great actually work though.
are we sure the customer is not unplugging the speaker while the amp is on.. this will blow the fuse in a heart beat. I ask because I had a guy doing just that, in a way, he had a break in the speaker cable and it would open and close, changed cable.. and fuses stopped blowing. Great Channel lots of god stuff
Do all amps need bias adjustments after a tube swap? The mail order musician supply companies have been selling matched tube sets for decades as an amp upgrade with no mention of biasing. How many guys like me thought they were plug and play like most other electrical components?
Welcome to the Marshall DSL 100 bad phenolic board problem. This is a known issue. It is a problem in the manufacture. Despite that Marshall will not warranty any of it. Fixed one of these too.
Greetings i have a question
How do you het a new main board?
I believe there is a revision 20.
Anyways i have a friend that has one in storage in hes garage for years.
Be cool to fix it right.
Thank you for sharing.
I have had this problem before. Pre 2003 dsl's have that problem. The material the board is made of becomes conductive once it reaches a certain temperature. Hence the bias drift and fuses blowing. A very common issue on these amps.
This was a weird one. I actually suspect the original board might still be ok with my previous troubleshooting and solder reflowing. It's possible. I suspected the known bias drift at first, but given what I found with that pair of tubes, a new set of tubes supposedly, now I'm not so sure. Customer wanted to replace boards anyway and be done with it. These amps sit in a jam rental space and he needs them working. Old boards are, well, you know.
About ten years ago my friend got the JCM 2000 TSL. I listened to it and liked it enough to get the 60 watt version. Not long after that he started going through output tubes like crazy. That was before the drifting bias issue was well known. Of course just outside of the amps warranty. Needless to say he doesn't use Marshalls any more. I never had any issues with my amp it still has the original tubes. I'm sure if I used mine like he did I would have a different story. I find that I enjoy the clean channel of these amps more than the crunch or lead. They are surprisingly wonderful clean amps with quite a lot of head room and a decent reverb. I think blindfolded people would think it was a Fender. Which I guess isn't a big selling point for a Marshall amps. LOL Great video and I am happy you left in the small irritating things.
got one on bench B+ @464= 37.5ma @70% ... do you recall your B+ on this amp/tube set load?
"""You Gotta Know When To Hold Em, Know When To Fold Em" Kenny Rogers
I probably would suggest an Orange Tube tester or if the money is available an Amplitrex AT1000.. I have had so much troubles with duff tubes especially in 4 tube Output stages..
I had problems with JJ EL 34s several times!
While you were pulling the connectors on the original board, I noticed R19 appeared to be cooked and cracked??
Yeah they probably have a special tool to put those standoff on too.O you said it. O my god what a nightmare. I use to send my Major out but then I notice it was getting Hacked so I do it myself now. Kt88s are Fantastic Tubes but it's hard to get a good sets. Once I hear or see anything going on with one of the tubes I change it out Before it does damage.I had a tech Buddy that did great work.In another head Plush 100 w head we used RCA 6CA7s turned out to be very stable replacement for EL34s Any Who I enjoy watching your Videos. I don't have the patient you have. c];-)
Hey didnt know you can get those mother boards to buy.....
Seem if the fuse blowling theres a short on the Ac side on the input section..
Would labeling little bits of tape and putting those on the wires work? Like put "w12" on the purple wire, and such.
Eh, takes longer than a video and if they fall off, you could be screwed.
Alan W that's exactly what I would've done.
Still no white coat, surgical gloves or mask. . . tut tut ;)
Alan W I did that with mine
The old saying, a picture is worth a thousand words. And with today's smart phones, faster too.
I am sure that it’s just a bias drift problem. It is very common with these amps. The boards become conducive. It is actually not that expensive to do for a great sounding amp compared to buying a new JVM. I own a TSL100 and have owned a DSL100. Mine was blowing both fuses before I had the bias drift mod done and the amp freshened up. I also have 2 friends that have had the same mods and it fixed all of the issues on theirs too. Our tech has literally modded hundreds of these. He said that they are great amps especially once the bias drift problem is fixed. They could not not figure out why they were having the bias drift problems for years. Now it is a common and easy fix. He said that he rarely replaces the whole board. He has only got a couple of them back after he done the bias drift mod and freshened them up. He also says that the factory bias is too high. He biases them at 64MA and they sound great and very rarely have problems. The bias drift problems can cause power tubes to fail too. That is what happened to one of my friends.
I suspected the common bias issue up front, but wanted to do standard troubleshooting first in my last vid on this. The issue seemed to be resolved. But then a tube issue (which maybe have been an intermittent internal short at first began happening, so that muddied the water. Given that the amp was still running away, even after replacing the old board, it might be possible my initial tinkering fixed the old board and all that was needed were output tubes on the left side.
Marshall needs to wake up and quit biasing their tubes so hot. 45mA a tube was probably fine for fresh Mullards in a hand wired amp, in 1971. These shitty circus boards and the tubes they make today can’t handle the old specs. Most 6L6 Fenders I’ve worked with were biased cold at 30mA. One exception was the SuperSonic 22, which was biased too hot IMO for current 6V6’s.
The Guitologist, I wish that I knew how to do this stuff. That’s why I watch the videos. I was just filling you in on what our tech was doing to these amps. It has become a really common fix for him. Keep making the great Videos!
More I watch, more I appreciate my old PTP wired amps 🤯
Old computer motherboards, and new one's in general do not come with the nylon standoffs either. These are supplied with the case. Of course there are many versions of the standoffs and not all fit the boards and cases. Your right, should be included with the boards tho.
FYI.
The bias adjust board on the back has the pins inverted!
The left adjusts the right hand tubes.
The right adjusts the left hand tubes.
As a Mesa Dual Rectifier owner, I've watched your awesome video on the Roadster already. Very fascinating and educational. Interestingly, as much as the Roaster has a reputation for being complex (bells and whistles) that seemed very well thought out and designed, compared to this. This particular Marshall just looks cheaply made. To my untrained and unprofessional eyes. Either way, your videos are great. It's fun to watch a pro walk us guitar players through the designs of our amplifiers. Thank you.
ok, entonces el problema era un tubo el34... hacia falta cambiar toda la placa nueva??
Feeling your pain man. Holy crap that's a lot of push on connectors! No wonder they fail. Those boards should be military grade and about twice the thickness. How much could it cost? Did they ever improve in later versions of the Marshall's?
There are bean counters in purgatory installing stand-offs!
If I worked on one of these monstrocities, I would have to video the disassembly to document it as you do. Is that how you got started videoing your projects?
Not quite, but it's a good story. :D
Do tell in a SPF! I'm curious how you and others got into creating establishing their channels. Planned or happenstance?
I'm making a sign for over my bench that say's 'NO SMOKING ZONE !'
I'm not a fan of those connectors, but they do work and thats not were these boards fail. These board fail because the supplier built crappy boards, and on top of that, wrong parts values were installed.
Diggin' the jazz tunes.
13:44 This is what I had commented on in one of the previous parts of this series. In particular, where to get these stand-offs? You suggested a supplier, but I did not see they had these. I *completely* agree about the ridiculousness of new board not including fuses or the stand-offs. For the price I paid, just charge me $10 more and save me from the hassle! *Cmon Marshall* I chewed up some of my stand-offs removing the old board BEFORE I unwrapped the new one because I made the mistake thinking the new board would include them.
That layout seems optimized for something other than maintenance
Wow for a tech you really should have a tube tester. If I were the customer I'd be pissed.
Brad you've voided the warranty on the board because you didn't purchase and use the $400 Marshall nylon standoff remover tool :-)
And when someone tells you he can pick up a Marshall DSL 100 for cheap what do you tell him?
Never would have thought I would prefer classic elevator music. Today's music played in stores/restaurants will drive you nuts.
After watching your channel for years i can certainly see the difference between the older "point to point" amps and the newer circuit board technology.... Interesting how much simpler the older stuff is compared to newer technology. And ironically the older stuff seems to have much better tone.. Go figure.....
On these Marshall I use a thin marker to number the connectors
Wampler Pinnacle and a Quilter look better every day. I think I'd rather build them both from scratch than do all that.
And? I L O V E the Dual Super Lead. I really do. It's been my 'Guitar Center Test Amp' since they came out. But...yeah, going Tech 21 in 2003 was the best thing I ever did, in retrospect.
Oh yeah, great :D Some of my friends had those affected DSL-amps (The ones with issues are the ones from 2000 until 2006 or so). As soon as those amps worked well, they were laughing about me because of my "old shit-amps with only one channel"...
Well, they ALL had the Motherboard-problems, starting a couple of years ago. The boards split internally (somehow the lamination seperates itself) and then you have the issue with the BIAS running away and killing the Output Tubes very fast, therefore throwing the fuse etc. etc. etc.since you have all sorts of currents on spots, where they shouldn´t be.
is this where one says Don't buy a DSL?
Even the new boards need the mod for bias drift , and certain circuits need to be changed 😇 , all boards made in England , other Marshall amps made in Taiwan .
Nice videos 🙂
I had one of these amps it was nothing but a money pit, when i talked to the dealer about them, they told me they were the most returned amp for faults
Yeah, lots of known issues with these. And they seem to eat tubes.
Haven't gigged on a regular basis for over 10 years but seeing this DSL vid is a warning.
Respectfully disagree. Marshall amps have been my amp of choice for 40 years. Tubes last fine if you don't crank the bias up too high (guess what most metal heads do? it's no coincidence). I would admit that Marshall had a significant issue with the PCB material breaking down in the 90s around sockets and I wish they did not pcb mount them but I haven't seen that PCB issue with the more modern ones). I changed a few PCBs over the years and found the standoff switchover pretty easy if you use long nose adjustable tongue and groove pliers in line with the standoff not across them like you were doing. With the stand off in line with the jaws you can position, squeeze and push home all in one movement. I kid you not it takes less than a 1 minute to do all of them.
Some JCM2000s are problematic and some are not. The ones that are, can be "permanently" fixed and turned into absolute tone monsters. Upgrade the irons, add a choke, replace main board and bias around 75mils. Don't forget to fix the 16ohm jack, else you could blow fuses due to open load oscillations when the other output jacks are used.
So basically rebuild the amp
Thought I saw where Dave Friedman was have a lot of of trouble with EL34's from J.J.
A company like his buys them in bulk, I'm sure. Then probably does his own weeding out. The matched pairs from AES are usually ok. These were not.
Yeah, but, it got so bad that he stopped getting ALL his EL'34's from J.J. I always heard that J.J.'s were the best. btw, dig your channel & I'm in Louisville, too. Used to work at Music Warehouse & Mom"s Music.
I hate JJ tubes...give me some SED Winged "C" any day.
Hah, I got 5 minutes in and all I've heard has been "connector *a* goes to (non-matching) connector *b*" over and over... I remember this nightmare! Sorry Brad! I've kinda been there too, but even the Line 6 and Roland amps aren't that bad...