on the JTM45 layout there is a 16uf cap connected to the pin 6 of the V2 tube
at  the JTM50 layout there are two 33uf caps
whats the name of this section and what is the sonic result of these different caps?

just a picture of a little amp meeting in germany
you can see a overtone HRM, my JTM45 plus a 18 TMB...

@ROE

I did some remarks on the JTM45 layout... could you check if its right??

marked with "A"
the first preamp tube is called v1.  see the cap on pin 3 and 8 (shared cathode) reduce it to 25uf, 16uf, 8uf or even 3.3uf

marked with "B"
see the caps after pin 1 and 6 on the same tube - reduce them to .018 mustards (or even .015) - see if you can find originals - .018 aint that expencive.

marked with "C"
see the last mullard or mallory tupe caps at the other end of the board (the phase splitter) - remove the 2 .1uf and try a .047uf, .033uf, .027uf or .022uf

marked with "D"  leave unchanged??

same question for me... I want to put EL34 in my JTM45...

Hello...
V2 and V3 position: JJ 12AX7 / 83s
V1 position: EH 12AX7
nice combination....
the same in my Ceriatone 18W

Hello... I already own a wonderful ceriatone 18W TMB and a german JTM45 clone...the tone of the JTM45 clone is not what I espected, the sound clips of other JTM45 are much better (Ceriatone, Metro)
 I am looking for some nice clean sounds, warm but also a
nice overdriven sound like the JTM45 or the 18W
does the HRM Bluesmaster cover this?? I want an amp which a wide sound spectrum... playing mostly blues and rock like ZZ Top, Free, Cream, Led Zep
but  I also want to play Peter Green, BB King, Clapton stuff....
best would be a Fender and a Marshall in own amp