[Mike D]

Greetings from the near North. 

My Jolida 302a was mildly modded by Scott F at a Christmas hang years ago.  He and others got under the hood and upgraded the coupling caps between the EL34s to Aurica Thetas (.22).  The power supply caps were bypassed with an unknown brand.  The 4ohm taps were replaced by some fancy solid copper or brass connectors. 

Yesterday I called Jolida to see how and if I could run KT88s and KT 120s in the 302 by changing the tube resistors (grid resisters?).  They confirmed that I can.  I put in 4 22kohm resisters and put my 4 best EHKT88s after testing a pile of them with the B&K tester I got from Scotty years ago on a vinyl run.

The difference was an huge increase in midrange overtones ....  because I am only using the jolida to power the midrange panels of my magnepan IIIAs actively triamped.

Question:  what do I have to do to get the jolida to run quieter?  I can hear a small amount of hum and hiss (normal amp noise).  Should I try a power supply cap capacity increase, change resisters in the signal path, or diodes, or anything else? 

Thanks,
Mike

[mjosef]

The basic mod 'package'...
http://www.ellisaudio.com/jolidamods.pdf

I recently did several other 'parts upgrades' that I thought were worthwhile, replaced the clunky speaker terminals, replaced the RCA input connector (my unit came as a power amp, no balance or volume pot in the signal path.), replaced all the tube sockets: ceramic-gold for all the small tubes and teflon-gold for power tubes.
I still get a little hiss but my ears has to be within 6" of the speaker, inaudible from my listening position.

[Mike D]

http://www.partsconnexion.com/product7567.html

Are these the right size diodes?  Sorry for such a basic question, but I couldn't find specific amp or volt ratings in the archives.