Tracking Tube Amp Noise - Marshall JCM2000 TSL100 Board Replacement & Troubleshooting
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- เผยแพร่เมื่อ 30 ก.ย. 2024
- In this video, we'll first replace the main board on a Marshall JCM2000 TSL-100 Triple Super Lead Head. Then we'll trace out the source of some noise, which becomes a good impromptu tutorial in how to track down the source of noise in a modern tube amp. This is Part 2 in a series. Here is Part 1: • IT'S BAAAAACK! Marsha...
The customer who brought me this requested up front that I replace the main board, so that's what we'll do.
Stay tuned for a possible Part 3 where we'll explore various ways to modify the original boards on these if they have become conductive.
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To those asking why didn't I swap or pull tubes to diagnose first, it's a good question... That's where I'd begin too if the amp was not open on my bench. I'd pull V1 and look for noise to persist. If it persisted, pull V2. If noise disappears, you've found the stage, but not necessarily the source. If you're LUCKY, you've got a tube issue, but not always. Since the amp was already open, this made a better video than just pull V1...still noise...pull V2...noise gone...maybe it's the tube...swap tube...get lucky. I'm not recommending everyone open their amp and trace the problem in this manner for the word "go". Sorry if I gave that impression. But this would have caught the issue whether it was a bad tube (which was the case here) or a bad something else. Hope this helps someone.
The Guitologist i have an Deluxe Reverb 68 reissue that had exactly that noise, i was lucky it was just a bad preamp tube, dont know which cus i got a set of quality replacements for all of the preamps. Love your videos Brad, keep up the good work 👍🏻
Thanks, Thomas.
The Guitologist hi, if you are interest I’ve encountered the standard bias trouble with my 1997 DSL100 (red plating the power tubes) and I used an extra little board (5cmx8cm) connect to the power tubes which redesign and solve the bias problem on these earlier versions!! And that solved my trouble like a dream!! So if you want I send you all the infos, pcb, part list and layout in PM!? By the way your videos are AWESOME!!! Thank you so much!
Good Job Brad..!! I wonder how much noise this amp has due to the fact that many of the harnesses are NOT twisted?? Having a good tube tester is always simpler. I usually use Amperex on the pre amp side.
any chance you could send that my direction? Having a nightmare with a JVM 410H
This and your last video, show exactly why I like this channel so much.
You are not afraid to show you are human and leave in mistakes, which you could have easily edited out
I had one these set on fire while playing on stage, completely burned out. The shop said it was due to tracking under the output valves. The vales used to really glow too hot.
friend of mine had one of these 2000s for 6 months & 4 months of that was spent at a shop ,, nothing but trouble ,, getting hot beyond normal ,, on the other hand I've been using a JCM 800 100w 2ch for almost 25 years & NOT ONCE its been to a shop,, still has the same tubes I bought it with 25 years ago,, same caps & everything,, OK cheers !!
Brad.
Your playing rocks!
Thank you for putting out great content and sound values.
Have a good one.
Old EL 34s ('60s) were never a problem. The only time I lost one was when someone tipped a pint of beer into my mesh-boxed amp. That cleared everything out with a bang.
You should get a tester. :)
As you adjust the bias between each pair of tubes it is definitely a balancing act. It is also beneficial to have a four probe bias socket tester for beast amps like these. The last TSL100 I worked on had one single tube pulling a butt load of current. Using the bias probes allows me to swap tubes around to see bias shifts quickly. My problem was that there was just one tube cooking at 85-95% dissipation. Point is that setting the bias the way Marshall intended would never reveal that issue with one of the tubes. Perhaps this is what was going on with that one tube in this video that looked like it had taken some heat.
I have a thermal imaging camera that would tell me that too.
When using Marshal amps it's best to play with an English accent.
These motherboards apparently had wrong components placed at one point in their production, with temperature-dependent resistors being placed in the bias circuit: web.archive.org/web/20170511053249/www.lynx.bc.ca/~jc/TSL122.html
Those Native Sons straps are really cool - wish I had the money to buy one!
Get the organic hemp backing if you get one. Best woven strap I own! And I own a LOT of woven straps.
After 25 years messing about with tubes in both Hi-Fi and guitar related activities as soon as I hear that telltale flutter/rustling sound I know it's almost always a defective tube especially if it's got JJ embossed on the glass. God they're a horrible brand. Noisey, unreliable and don't even sound that great. If you can't afford NOS get Russian manufacture or even Chinese over JJ.
The Chinese Shuguang 12AX7's are superb .
Yeah just read that about the chinese tubes. Closer to spec. than all the others
i so agree with you.people think jjs are some sort of great tube.there glassy cheap garbage that to my ears are all tops and bottom with a clear lack of rich midrange.god to know im not the only one who feels this.ive been sourcing nos teslas and there such a different sounding tube ,especially the el34s.my hand made marshall stereo power amp i had built for me has 4 el34 teslas from the 80s that are still good to this day and sound nothing like jjs
I had TSL 100...I love it.....at first ...started making screeching noises,replaced the tubes...matched set!....noise came back everytime they heated up! Brought it to my friend...you might have heard of him TONY BRUNO...BRUNO AMPS! He worked on it for hours still kept running crazy.. The Bias kept going a drift,and still crackeld! The cheap ass design that Marshall uses allows the heat to breakdown the board overtime! Tony worked for Korg/Vox/Marshall,and said the amps are junk compared to the earlier models...took his advice...got rid of it!
yea for some reason the reverb doesn’t work on mine ,anyone have any ideas why?
I'm glad I set my mind to never going with first impressions. My first viewing of your channel was a S*** Friday vid and I found myself coming away from it with the wrong impression. Car guys can argue all day about different makes and models. Both sides are right on some of the particulars. It is most often just a matter of personal tastes.
Your channel has become a favorite. I get a bit nostalgic looking over your shoulder. Back in '71 I had completed the first six months with U.E.I. (University of Electronics Institute) in Louisville, KY. (Done through the mail) with perfect grades. When it came time for the year and a half in L'ville, our dad told me, "Nobody paid to send me to college so I don't see why I should for you..." I had paid for the first semester with my savings from working on other farms. Since I'd graduated from school at 17, I had no chance at financing without a co-signer. So that put the brakes on that. I also did some time in IT as service manager for my professor/employer at the local community college twenty years later. I once had a Wyse keyboard computer (don't remember the model number but the entire system was in the keyboard and just had the power chord and monitor cord externally) waiting on my desk when I came in to work. Some sadist at Wyse had designed the thing with the 3-pin (soldered to the bottom of the motherboard) battery at the bottom of everything. I was given the task of replacing the battery with *NO* documentation, going to the customer's home and setting it back up (they were at work) and then being out at the college for mid-terms at 1pm. (You wouldn't have wanted to look over my shoulder and listen in on that one... [Grin] )
I had a blast building kits and was fascinated by electronics. The advent of calculators would have helped with my dislike of mathematics.
Getting to follow along on your projects is very enjoyable. It is a gift as well as a sign of your comfort with what you've learned along the way that you are able to talk through your thought processes while troubleshooting a project. If only I had your experience maybe I could get my old 10 channel, powered Carvin mixer working again... :( This was one of the 1970s models made back when they still did military style wiring. I look at the schematic and compare it to the guts of the mixer and just can't get the feeling that they are both the same thing.
Thanks for watching. Shame your dad wouldn't help you out with college. You can learn all you need to know these days from books, TH-cam, and diving in.
A faulty JJ strikes again! Who knew...
this guy.
Appreciate the schematic and tech fault find lesson but wouldn't you just start swapping existing tubes with known to be good tubes as that would always be the most suspect origin to pinpoint the fault ..?? I'm not a pro tech but that would always be where I would think to begin the process.
Thanks as I always learn something re: trouble shooting from your channel
amp was already apart,next question?
I bought one off the first tsl122 combos , I had my own lightshow , it burnt out valves at an alarming rate ,literally as soon as it warmed up .The bias drift was unbelievable , it would go up to 20 v !!!!!!! I retired it ,and by chance read about this bias drift on the internet ,people where changing lots of components and still no joy !!!! then someone found out that the material the board was conducting voltage through the board !!!! the only cure is to replace the board ,I replaced mine and it has been perfect ever since !!!!
I've heard the odd report of a new board doing the same thing, but I'm aware of the fix for the old boards. I'll do another video showing how that's done.
Very interesting I had the same problem with my TSL 122 and in the end after having alot of problems Marshall rebuilt one main board and changed the tubes and the I started to get the same noise as you had in my other cab and I sent them both back to get sorted even though they were brand new at the time and under warranty it still makes you wonder and from what I know they have done a major board update to fix the bias problem once and for all but I am having a problem with forking out an extra £400 plus just to fix a problem that should not have been there in the first place. If I had known at the time I think I would have gone with the JSX which were going for about £1200 at the time but since I was building a stereo set-up it means two of everything. I still have the amps but I use my Bandit 112 for home use most of the time. Keep up the good work very interesting vids.
Is the demo at the end through the test speaker? Sounds a bit thin, but excellent playing- I would love to see more Marshall vids.
Yeah that's just the test speaker sitting face down on the bench. :)
I purchased a TSL 100 for about $400 and it was red-plating a power tube. I replaced the mainboard and tubes and it rages. The only gripe I have about this head is that it runs at about 6.2 million degrees and I always run a fan at the power tubes. I have a JCM 900 and it just gets warm while playing for hours.
Marshall just replace the motherboards on DSL's and TSL's - the original boards were crap quality and break down internally over time. They had new ones made that "should" last. I dont even attempt to repair them any more if customer isn't prepared to pay for new boards.
This right here is one good reason that I will probably not ever buy another tube amp with circuit boards in them.I have also built one tube amp and learned a little more. There is just too much that can go wrong in a circuit board to suit me. In 2012 I bought a blues jr, and a hot rod deluxe,brand new. Within one week the blues jr., blew up got another and it messed up and within about a month one of the buttons on the hrd messed up.I still have an older blues jr. that I bought used.Had I known what I know now about tube amps, I probably would have kept them but at the time, I knew nothing about tube amps.I just don't have the money I used to have to buy gear that does not hold up. I have gone back to solid state for playing around the house.
It seems the first benefit of circuit boards is that amp designers can fit all these overly complicated circuits into a chassis. Many guitar players will see all these switches, extra jacks and buttons and get all excited. Not only is it nightmare to repair but as a player it is just overkill. It begs the question just because you can do something does it mean you should.
Those proprietary Marshall stand-offs are (M-SPCR-00045) and $5.95 each. Sharing in case anyone else is in the same boat I am.
Nice shirt, I have that one and the Taylor Swift one as well.
Have you ever worked on the old marshall vs100 amps? I picked one up last week and it's a bit noisy. Not sure of that's just the nature of the beast or not. It was supposedly service at a guitar center last year.
LOL I wish i had a dollar for every time I was repairing and amp and said "Man I hope that's all that was!"
Don't let those amps over your door......ever!
nice troubleshooting. BTW, I want a guitar duet between you and Richie castellano. the analogic world meets cpu. :)
I've taken off and gone stupid many times. I always seem to be biased though, especially when I'm properly wired.
Some pretty tasty licks at the end there! Wasn't expecting to be more interested in trying to figure out what you were doing there than the fix! =) I just had the same issue on my JCM2000 50w with the noise. It was just a preamp tube (brand new ones). Thank God! I think I messed it up trying to bias the power tubes. Can you mess up pre-amp tubes by playing around to much with the bias pots? Going down to 20mA and back up to 60mA etc..? Tube Depot also gave me some bad power Tubes. Got some matched JJ EL34L and they sounded horrible, thought my amp was broken. Sounded good again when I just put the old regular Sylvania EL34's. Not sure if it was because the type of tube "EL34L" or if they were just bad tubes.
I have the tsl122 combo ,, replaced the board to rev20 and seems ok ,, bias holding steady at 91mv which is stock ,, I tried setting it lower but sounds terrible , 90 91 is the sweet spot on the combo and runs really cool no issues so far ,, I would not fool with this amp if it did not sound so good up loud ,, I have had the mesa boogie rectifier and the carvin ,, and the jcm2000 live sounded the best for me ,, the clean is really punchy and super , loud this Marshall is meant for a strat
Hello Mate, thanks for the video!!! I got TSL 100 JCM 2000, and gain is so weak, gain is almost 9 on the crucnh channel but there is no gain at least, preamp tubes also new.. but result is same i wonder that have you any video that kind of problem? By the way i faced same issue with all channels , clean-crunch and lead😢
Hello... Awesome video...
I have a JCM 2000 DSL100 and have a lot of hum when I am not playing. I also get a lot of crackle with the pots and even push buttons. I had a tech tell me that he doesn't think the pots are dirty and that its probably voltage from the MB? Does that even sound right? I was going to order a new MB and dont know if that will fix my problems. Any help is greatly appreciated :)
Paul
Great tutorial on the TSL-100. May I ask where I can get schematics for the TSL-100. Thanks. All the best & stay well !!!
Doesn't the Marshall 2000 have a bias drift problem? And there's a klit from "Dr. Tube" to fix this problem? The kit may be cheaper?
had a quick question for u regarding my TSL122.
emailing 2 brad@gmail failed
its 1999 made. works good for the most part but occasionally blows the HT fuse, so much so, that the previous owners installed a different fuse holder probably because he gets the longer fuses for free, maybe - who knows. I did a visual of all the components and the PCB's all looks well. The bias is set 87VDC on both sides at full power. Found another video on youtube that shows a solution for thermal conduction on the PCB itself. basically isolate pin5 from the main tubes and solder a jumper to the associated resistor.
th-cam.com/video/Yz_v-XK1PsU/w-d-xo.html
wanted to get ur opinion on this b4 i do it - thinking it would be good preventative maintenance as i cant order a rev20 board anymore + I hear those also have issues. Have u ever done this? mod looks a bit like the DrTube bias fix.
FUUUUK after watching these 3 videos, I just want to say thank you. I want NOTHING with Marshalls name on it. Modern amps are just pure shit. FET's ( tube wanna be's ) and all those bullshit boards and jumpers that go from hell to high-water...Fender and every other brand has this type of shit in it these days. Pay more and get less...
how much do these heads cost? wouldnt it be nice if marhsall used some better caps? those sanwa electrolytics are pieces of total shit. I do alot of crt television repair for arcade games and those things are piles of junk.
does the Marshall JCM2000 TSL100, break easily? is the jvm 210 H better? please advise me thank you. because i dont know which one to buy.
Confused these are dl34 tubes which are 25 watt tubes with 70% is 17.5 watts that should have a bias of around 36 to 40 mv not 70 varies of course on plate voltage
my tech and what brad is sort of saying is avoid this piece of crap amp,the jvms are better quality ...just....extremely bad design.to much heat on the pcb board
i have the combo version of the tsl 122. new tubes, i have NO output to speakers and NO voltage on the bias adjuster. Do you have a video that adresses this problem. It's not low it's zero
thanks
Had exactly the same problem and this helped a lot in troubleshooting it! Thank you!
I must have got lucky, I've had a TSL60 head and cab for decades and not a spot of trouble, still got the same valves and sounds great.
Celine Dion?.... on your shirt :)
Dang man you can shred a little bit! And with finger picken too... good work.
I get this very light crackling in my tubes I believe it is in my Marshall DSLHR100 head.
I'm going to buy.............an acoustic!!!!
I Have A TSL 100 Marshall Head & No Sound. How Can I Send It To You For Repair ?
Test the tubes ---- 6CA7 will do it!
Same for me but just in 25 watts !?!? Any solution ? Thanks :)
Hi Brad, you Tube Stuff Nerd (such a non sense in these two words, tube and nerd lol)
These few words to say I'm really fond of your amp surgeries, modding and so on. I learn so much, and reminds me some memories (trying to fix Marshall DSL or my Mesa Roadster nightmare)
Greetings from France :)
Thanks for watching.
This is what you get when you buy Marshall and Gibson now... Junk.
Damn Brad I like the way you play, your phrasing is killer!
part 2 of How Many Times Can I Fuck Up???
The main problem was Tube V2 was making noises
Guitar playing and amp sound great! 26:00
Another great mod to do on these is to remove that 7W 270 ohm resistor and replace it with a filter choke. Do that to all these modern Marshall's. Just did my little DSL40 with a choke and a new output tranny. Night and day difference. Just put a filter choke in a friends JVM210 with a new set of 6CA7 tubes. Plus removed the C83( I think that's the number) cap on the input. Much more old school sounding with out all the fizz. He loves it now.
@28:00 great playing, now, PUT A TORTOISE SHELL PICK-GUARD ON THAT TELE FOR THE LOVE OF MIKE !!
Jesus dude you were amazing at the end there
All them damn connectors are a pain in the ass.
Okay I've watched all 3 of the Marshall videos and my faith in JJ is completely gone now.
Having some of the same issues with my TSL 100. First time seeing the shields inside the EL34s (v7 and v8) glowing red! I've watched Tony McKenzie's video about changing the motherboard to issue 20, and decided to bite the bullet and change it out (it is currently shipping my way). One of the things he suggested was to solder electrically close the ground "switch" of the 16 ohm speaker jack closed to prevent putting an excessive load on capacitor C46 by the edge of the board. Something to consider... great video! Thank you so much!
After watching part 1 and 2 of this "saga", I'm so glad I bought a Bugera 6262 Infinium head instead. : )
3:48 AM? I guess you can't sleep when you're having fun. XD
Nice Vid ! Dig the hunt ! Don't know why JJ Tubes are so popular. I've got so many Microphonic 12AX7 and 6L6's. These Marshall High gains will find any weakness in the preamp section. Since I worked on many Mesa's I have a stock pile of Mesa Tested 12AX7"s, never had a Microphonic Mesa 12AX7. Not that their the best , they can be low gain or output in some amps ,but they are consistent . My fave 12AX7 has to be the NOS EI long Smooth Plate . Back over a decade ago I got mega gross for cheap . Now there not cheap everyone knows they were made the same as the German Telefunken's. So if you see someone selling old Boogie preamp tubes for cheap , get them !
These kind of videos I like, I need to do my JCM2000 DSL,so this is great.Thanks man.A lot of folks are changing out these motherboards ,easy enough ,but why not do a little more long term testing at the factory,so you don't have to change a large item such as this.Everyone needs a buck I guess.Thanks 👍🎸🎸😎😎🎶🎶🎶 Rock on!!!
I had one of these TSL's before but I sold after going the shop so much. Here I picked another one up recently that's a bit on the noisy side and the reverb only works on the clean channel. Any one ever run into that before and if so how did you fix it?
lots and lots of diagnostics,there's no quick,cheap easy answer to these questions
Boy,seems like those Marshall JCM2000 series Amps are junk.I heard they were the highest gain amp they had produced at the time.Seems like you have to work on them more than you play them.Kinda like the Volkswagen of guitar amps.Ill just stick to my trusty ol Mesa Rectumfrier.I hear they are a nightmare to work on too though.
Thanks for posting this ,.........I've watch both videos and not sure about JJ tubes anymore !!...haha!
Hi mate. My tsl 100 head sounds like paper being scrunched or a static sound. Please help. Board changed, new tubes. Leaking capacitor perhaps?
I'm in Santa Fe and just acquired a DSL 100, locally, that has the same problem. Amazing. I believe this will help me. Thanks.
You always show the good with the bad Brad, and your honest. I certainly wasn't impressed with Marshall's lack of attention to detail, and their fixing problems as they arise in a product that is already supposed to be fully engineered? Now I'd be somewhat hesitant to buy a second hand Marshall from the first few years of a models run. Besides the fact that I'd have to run down production dates?
My tsl reverb hummed like it had forgotten the words after changing the board, turned out I'd connected it up in reverse durrr!! I convinced my self it was a bad connection...,.. which I suppose it was!!
Well I guess that makes me the turd... Go Me! LOL :)
I was replacing the R7 resistor in my DSL about every 20 mins of uptime... Crispyyyyy!
always always put a fresh set of tubes.
Those are notorious for bias drift. I had a TSL-100 and it required me to replace the entire board. I found one cheap from a UK supplier for < $100 brand new. Once it was replaced, the amp sounded like poop so I sold it. Too bad.
Those JCM 2000 were infamous tube killer, with errant bias, unlocatable noises etc. When those was sent back for repair under warranty, Marshall often return a brand new one, pretending the original one was lost or destroyed by the transporter..
To bad as the jcm2000 are sounding quite good, but the serie earned a reputation of bad amps overall.
This also damaged Marshalls reputation , and opened the way for smaller makes..
Apparently there was a defecti on the first iterations up to the 7 (as written on the board) revision. Was fixed, but to late and the damage already done.
Did you try turning it up to 11? Lol. But seriously I love your video’s. Always look forward to new ones....even the non guitar/amp ones. Better than any reality show. Shit post Friday’s are awesome! 🤘🏼
i have this amp, it died, i left it for 2 years, took it to a tech, he said the transformer was blown, it was sent away, rewound, and he charged me $200, i took it home, sounded great, then an hour later i got a buzzing noise, and i remembered it from before it died the first time, the distortion also got a fuzz on it, so i let it cool and turned it off, and returned it to the tech, he looked at it told me it was sweet and gave it back to me, it started buzzing then it shut off, 90 mins later i took it to him and we opened it up, the transformer was SOOO hot!! it was stuffed again, hes had it rewound, says its over heating and he does not what to do, all this time i thought he was fixing it, but he just put it to the side, its been 4 to 5 months..... would you know what would be causing this?
KISS. All techs get reminded of it occasionally. Anyway, BTG is the best guitar player/ amp tinkerer that I watch on YT.
Nice job on finding the faulty tube...and showing the process of elimination to get there. This shows how to eliminate 100's of components in a matter of minutes, leaving only a few to troubleshoot.
P.S. I happened to notice the time on your laptop...late night or early morning?!
What are your thoughts about the (PPIMV) Post Phase Inverter Master Volume kit from Triode USA?
Please. I need to replace the registor R21 on the rear jack board. Can You tel me what is the exactly resistor? A link, please.
the ring you are wearing. my late grandfather left one almost exactly like that to me. its called a kentucky cluster and no we dont live in ky lol.. is that what yours is
It was going to be a Christmas gift from my Grandma to my Granddad in 1980. He died on her birthday, December 8, 1980, which was also the same day John Lennon was shot, and never received it. Years later, my Grandma gave it to me. I've worn it ever since My finger was large enough to wear it. Yes, I think they call it a Kentucky Cluster Ring. I've lost one of the diamonds from it along the line. I need to get another one set.
This isn’t a real Marshall. Motherboards? In an amp?!? Are me and my 800 missing something?
That looks as bad to work on as a modern Fender... actually worse I think lol
Hi Brad, another informative video. Always worth remembering that the only ‘bias’ is actually the voltage on pin 5 of the output tubes. Before looking for faults in the bias circuit just pull the EL34s and check that you can get the same voltage on all pin 5s. Also, if one side bias current is around half of the other side then you know you have lost one of the two valves in that pair. Cool playing as always.
Id like to know how much u charged for this?. All that work just for a bad tube. Plz be honest. Thx
Congrats on the use of the capacitor-blocked signal tracer probe. Those babies usually tell ya what you need to know.
Right!! I finally worked out who Bradley Govan is, LOL!
that rustling to me sounds like radio noise, like something is working as an antenna when it shouldnt be, now im not an expert on how tubes work, but if the tubes been cooked and the coatings burned off inside, would this be the cause of said noise ? electrons unable to be captured by the plate need to go somewhere...
Another Marshall I have to replace the board, hey guys just replaced the board. I have to charge the customer to replace another board... Wtf? Really? Why not fix the issues in the board eh? All these so-called technicians out there servicing these Marshall amplifiers and they all resort to just replacing the board.. why not just fix the issues associated with the board, I mean you're a technician right? You know how to troubleshoot right? There's only a few slight inconveniences associated with these early Marshall DSL 2000 boards. It's a simple fix if you know what you're doing.. I've been servicing these Marshalls since the day they were conceived and I've never had to replace the board. I've just corrected the issues on the board. Replacing the board may be easier for the so-called technician servicing the unit but it's very expensive and pricey to the customer.. if you don't know what you're doing it may take you some time to find the issues associated with the circuit board however, once you found the issues it's actually a very simple fix.
Maybe put the bias circuit on its own separate circuit board and do away with the dual pot control system. Then maybe take some of those inexpensive crappy blue resistors in the trouble areas replace them with good carbon film resistors and lift them off the board.. I just gave away a couple of the secrets the rest is up to you...
Read the description. The customer requested up front we just replace the board. I told them about the solutions like drilling out around the output tube pins and they opted for a new board.
By the way, you do realize when you make comments like this you come across as an arrogant asshole, right? If you’re truly passionate about sharing your supposed wealth of knowledge, make your own videos rather than typing feverish screeds on other people’s.
So, a power tube shorting afternoon heating up and a noisy pre amp tube. Nothing much to it other than figuring it out :-)
The only Channel I don't fast forward thought the sponsor portion of the video.
Brad,
Thanks for the new video! Very interesting. Have you ever made a video featuring your tube tester? I'd like to see that.
Great video as always brad, awesome to see uncle Doug back making videos too . And wills easy guitar is back up . Happy days 😁
I like the Ampeg VL502 more than a Marshall.
Same problem, same solution on a Randall RG50 here :)
Think I will stay away from both these amps.LOLOL
Brad what power tubes do you recommend for Marshalls ?
It does seem to be the pattern with most of these amps that the faults are most likely to be in the capacitors, the valves or diodes.