DSL 100 issue

[lastbrohemian]

first time posting, been reading these threads for 10 years now, very insightful, thanks guys.
but on the other hand, i found out about the lynch mod, wanted to try and bought one without really researching. this is 100% my fault.
I stuck one in a dsl 100 and only the worst thing ever happened, no sound! pulled it out immediately and still no sound unless you turn your channel volume up to 10, then you can hear something that resembles a signal. this was a year ago, and my amp has been used as a stand for my mixing board ever since.
now i got my second wind and am trying to do all the research i can to repair my amp. was hoping i can get some advice on where the issue would most likely be. i checked the PCB and everything looks fine. checked my modded choke and its reading 92 ohms with no ground short. ripped out my pcb (just not really ripped out) and everything looked good visually, checked with meter and capacitors and diodes checked out good but some resistors were not checking out, probably cuz im not gonna sweat them out and test. was thinking maybe somewhere on the tone stack board or the speaker output board? any productive input would be nice. please dont mention my neglect of research, i already expressed that. Thanks

 

[DamDoc]

Fuses?

 

[Joesatch]

id examine inside the chassis look for any burned components (resistors). might have pulled too much current. i think they only use 1/2 watt plate resistors on the triodes

 

[Jon Snell]

What did the 'mod' entail?

 

[PelliX]

What did the 'mod' entail?

The Lynch mod is a device that allows you to increase the number of gain stages in the form of a 'valve socket splitter':

Legendary Tones - Mr. Scary Mod - Handmade in USA, 100% Pure Tube, High Gain Module

Created in collaboration with George Lynch, the Mr. Scary Mod is a custom-modified version of the Hot Mod V2. Want to supercharge your classic Marshall (and many other!) amps with more gain without applying a permanent modification? Then read more below and welcome to the Mr. Scary Mod! George...

legendarytones.com

There are a few different versions out there, so it would be beneficial to know what was used here exactly and in which position in the DSL.

 

[rocker68]

1. Welcome
2. What tube position did you install the Lynch Mod ? V1, V2, V3 etc .
3. With correct working preamp tubes in place , try going into the front input then try bypassing the front input by going into the fx return jack.
4. Check ALL fuses including internal board mounted with multi meter.
5. Standard or reverse wired Lynch Mod?
Just swapping a pre tube with the Lynch Mod shouldn't cause Armageddon. ( Boat anchor itis )
Just saw Pellix's comment about which position.

 

[rocker68]

To be clear, you have the jcm 2000 DSL 100 correct ?

 

[Dogs of Doom]

What did the 'mod' entail?

The Lynch mod is a device that allows you to increase the number of gain stages in the form of a 'valve socket splitter':

he also said he added a choke... (mod)

 

[Dogs of Doom]

speaker plugged in?

which output?

 

[Leonard Neemoil]

Welcome to the forum.

If you look on their site, it makes no mention about the DSL 100.

Legendary Tones - Will my Hot Mod V2 or Lynch Mod/Mr. Scary Mod work in my amp?

Perhaps this is the most common question we receive here when people first inquire about the Hot Mod V2, Lynch Mod, and Mr. Scary Mod. And of course we also offer a reverse-wired version so that either model can also function in many of the reissue amps which the original Soldano Hot Mod could...

legendarytones.com

I understand the DSL 40 is the same circuit, so it should work though.

Not sure what will happen if the LM is used with a DSL 100, but hopefully you just popped a fuse.

Maybe email them and ask the repercussions of using the LM with your specific model of DSL.

Please keep us posted on the outcome.

 

[BakedBeans]

One note on your post: Resistors in a circuit do not need to be unsoldered to test their resistance (caps do). Typically when resistors fail, their resistance goes too high. Most common in resistors close to high heat (tubes), but also seen in amps that were kept in very damp conditions - I've seen such. Recently refurbished a '66 Vibrolux reverb that had been in a guy's moldy basement for 30 years. Several of the carbon comp resistors literally had crumbled from the dampness.

 

[PelliX]

One note on your post: Resistors in a circuit do not need to be unsoldered to test their resistance (caps do).

That's a very misleading statement; you have to be entirely sure of the circuit around it. Even then, in-circuit measurements are not entirely accurate in many cases. Just consider two resistors in parallel or a resistor and a coil, etc, etc.