New 18 Watt TMB Build (Mojotone Kit)

[72Blazer]

I just completed this build with all new components.  Sounds really good and really quiet with the exception of two very scratchy pots on the master volume channel (Gain and Treble Pots).  I' cleaned both pots to no avail.  Amp tech stated "It is very unusual to have 2 bad CTS pots.  Because these are on the same channel I bet you have a leaky cap somewhere allowing DC to pass.  This would explain why you can't get rid of the scratchiness with cleaner."
Anybody ever run into this type of issue?

[72Blazer]

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[72Blazer]

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[72Blazer]

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[sluckey]

Anybody ever run into this type of issue?

Yes, we all have. Very common. Most likely the 500pf treble cap. If not that one then one of the .022s.

[72Blazer]

It was the 500pf treble cap!
Thanks

[72Blazer]

Well it sounded great for about 5 minutes now I got an electrical storm in the MV channel which I did not have before. I've only got one more 500pf cap left in my supply.  I'll try that one and if that don't work I'll start changing out those .022s

[72Blazer]

I guess the third time (cap) is a charm...

[Willabe]

You have to be very careful with those silver mica caps, too much heat soldering them and their toast. 

[72Blazer]

Thanks for the tip-I'll use a heat shrink from now on.  Amp still working great but I sure miss fender spring reverb
Has anyone taken a similar amp and and added reverb?

[sluckey]

That's a good question for 18watt.com.

[dude]

Yes, several guys at 18 watt added reverb but that was several years ago. Maybe go over there and check it out

[Bieworm]

JMPGuitars designed an amp called " tremolo TMB reverb ". I have built 4 of them already and IMHO it's the best amp I ever heard. I know that's subjective, but nevertheless you're welcome to check it out on 18watt.com. you're very welcome!!!
Not trying  to steal you from EL34world or anything. Great guys here en great Help too...

[JB]

Marshall did make a version of the 18W amp with reverb, the "Master Reverb".  Very rare beast, I had a chance to play one and look inside.  They used a single ECC83 with the send half tapped off the first stage anode and the recovery stage feeding into the second half of the LTPI.  3 x ECC83 in total, single channel with tremolo.