JCM2K DSL

[sahlomonic]

Bought this cheap from a guy who said it was whisper quiet even when the volumes were dimed. Brand new power tubes, unknown age of Mullards in the preamp.

PT and OT was changed to Classic Tone

Not a very good wiring job, but looks to be hooked up to the right spots per schems and Marshall Forum.

Any quick suggestions here? Have yet to put a meter to it, so I don't know what voltages are reading.

 

[Dave M]

Any quick suggestions here? Have yet to put a meter to it, so I don't know what voltages are reading.

Yeah, get it properly wired. The BS splice jobs are BS.

 

[sahlomonic]

Found the main culprit, then reworked every connection off PT and OT to have proper spade connectors and dress it up a little. Now it sounds fantastic.

 

[sahlomonic]

Update:

Found R8 was also toast. Measured 1.6M. Explains why I was getting 24v bias on the right side. Replaced with new 1 ohm 1w and was able to get proper ~90mV each side.

Now ...

It's quiet again. Will keep digging, but at least the board is Issue 20 so it cuts down on factory failure a bit.

 

[sahlomonic]

Another update:

Found out the old Tung Sol 12AT7 I popped in the PI slot was the cause of the latest round of super quiet sound. Put in the Millard that it came with and roaring to life.

Since I solved that I put in a 3H Hammond choke. Really digging this amp now!

 

[Laputan Machine]

The green channel on those comes very close to MV JMPs imo.

 

[glpg80]

You gotta post some clips with the new iron and choke installed. I’m sure it sounds great!

 

[CLUBTURBO]

I Think The JCM 2000 Line Is Amazing Sounding.
I Have The TSL 602 And This Baby Is A BadAss.
I Use Two Plamers With This Amp Too.
That Really Helps Too. PGA-05 And PDI-03 (16 Ohm)
Normally The PGA Gets Hooked Up As
This Unit Really Makes The Amp Sound Better.

I Will Get The DSL Also At Some Point.
The Drift Issue Is An Easy Fix If One
Can Do The Research And Solder.

I Like The TSL For Its 3 Channels
And A Few Other Things.
But The DSL Is Still Calling.