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    What makes DSL lead 1 to lead 2?

    Dammit, one more thing. I would use at least 1/2 watt resistors for all of them. I know I said 1/4 should work but after thinking about it I would go with beefier parts. Also, the schematic I have (thanks Micky) of your amp is a rev 4 circuit. If your board isn't rev 4 there's no guarantee...
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    What makes DSL lead 1 to lead 2?

    Just my opinion here, but I really think that the resistor to ground after C34 (combined with adding R82) is gonna be the thing that makes the biggest difference for you. If you're feeling experimental, try just adding R82 first and checking it out, then ad the 10k to C34 and give us your opinion.
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    What makes DSL lead 1 to lead 2?

    OK Johnny, I got something for you. To make that Lead 2 channel match the Lead 1 of the original DSLs all you need is three resistors...but unfortunately it looks like to do it right you'll need to pull the board and probably buy two new caps. Here we go. Somewhere near the V1 socket there...
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    What makes DSL lead 1 to lead 2?

    That's not going to get you all the way there Johhny. That's only a third of what goes on to make Lead1 in the original DSLs. Theres a cap that gets switched in (or out as the case may be) in that same circuit as well as a change to the cathode of that valve. Just strapping that resistor is...
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    No reading when biasing JCM2000 DSL100

    1 ohm 1 watt. Like I said earlier, if I were you I would order a handful of precision (1% tolerance) resistors, I used Vishay when I did mine, and replace them both (R9 and R6) with the two that check closest to 1 ohm. In the meantime though, for your own good, please check out what's going on...
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    No reading when biasing JCM2000 DSL100

    Just out of curiosity, have you ever checked the bias before now? Has it ever had readings on both sides?
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    No reading when biasing JCM2000 DSL100

    I think you need to get an ohmeter in there and figure out exactly what's going on with that part of the circuit before you do anything. I'm afraid that just replacing that resistor might only result in turning it into another piece of charcoal. BTW, just because it's all burnt to hell doesn't...
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    No reading when biasing JCM2000 DSL100

    OOPS! My fault Anitoli, I read that wrong. You are absolutely right about the ground on those two tubes. Nice catch
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    No reading when biasing JCM2000 DSL100

    Anotoli, if you look at the bias board schematic the cathode still finds ground through pin 7 and the 33k resistor. Not ideal, but it's still there...I would imagine that would have a negative impact on the sound though. However, if that resistor was shorted somehow you wouldn't measure any...
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    No reading when biasing JCM2000 DSL100

    Resistors can fail without showing any visible signs whatsoever. Solder joints can crack or go cold as well. If you had a tube failure it could have overheated one of the solder joints to the point that it no longer conducts...so don't just check the part, check the entire path from the socket...
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    Questions about Zener Diodes and JCM 800's

    OK, diodes do not add gain, they distort (clip actually). I realize that's what you meant, but I feel like it's important to know the difference. Gain refers to the ratio of output/input of an amplifier device. Diodes, in the simplest sense, turn a sine wave into a semi-square wave...and...
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    What makes DSL lead 1 to lead 2?

    I can't find a scem of this thing anywhere, so if you really wanna do this you're gonna have to either do a lot of continuity testing and write your own scematic of that circuit or give it to someone who can. It honestly shouldn't be very difficult if you have an ohmeter, a soldering iron, and...
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    No reading when biasing JCM2000 DSL100

    It seems to me that if the amp sounds fine, most likely the 1ohm resistor for that pair of tubes has failed. That would be the best case scenario for you since you can check and replace those parts without even removing the board. If that's the case, you may as well replace them both while...
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    What makes DSL lead 1 to lead 2?

    I don't have a schematic for that head, but the older DSLs have a little more going on than one resistor...it's two. lol. They both create voltage dividers but each has a different function. One just passes more or less signal to the next stage and the other slightly changes the characteristics...
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    Tung-sol 12ax7 bad for cathode follower = bad for P.I?

    I have no reason to believe that a Tung-Sol is always problematic in either position, but if it's bad for the CF it will almost surely be worse in the PI due to the higher plate voltage on the PI. I'd say try it before you dismiss it..opinions vary!
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    2000 marshall 1959 slp 100 problem - please help

    Well if that power light twisting/power loss thing is a coincidence it sure is a hell of an example of one. Just check around there a little to make sure it didn't do anything funny...touch anything/short anything out. You might even try removing the lamp entirely just to see. I've had guitar...
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    TSL100 Noise on Clean

    Have you checked your bias before and after the noise starts? Check into that. If it runs up higher on you (like 90mV+) after the amp warms up a little then I would say that is your culprit. If not I would be looking at a leaky cap in the clean signal path. You can replace every cap in that...
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    Brand new DSL100h problems

    Wall voltage...check it. And check your PI tube (V4 on older dsl's). It probably has about 330Vdc on the plate which will definitely cause crackling sounds. I don't know jack about these new dsl's but I do know what an overloaded PI sounds like.
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    WHYYYY GOD!! Super Lead sound cuts out wtf?

    He's blunt...but he's right. If I ever get cancer I'd want ATP to break it to me! Hit us with a schemo of that mod...just cobbling in a extra tube doesn't always play right with power trannys.
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    2000 marshall 1959 slp 100 problem - please help

    +1 to ATP and Ken. I have seen resistors that look pristine be completely open and ones that look like they were in a plane crash work perfectly. Never judge a book by its cover in the world of electronics. I bought a used amp a bunch of years ago that just refused to work right. A...

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