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Crunch preamp + 2x6L6 build
#1
Sad to see the old forums die... And good I managed to save some of the core stuff.

Anyways, I bought an custom wound output transformer from a friend that built a JTM45, along with the power trannie that is suitable for a JMP, so I had plenty of reserve with heater current, and the secondary mains were 320V, sweet!

So, preamp is a "crunch" core project from AX84:
https://app.box.com/s/00mgwpjdc16ylkn...

Output section is directly from this schem:
https://app.box.com/s/irv6w05yi9hx1id...

I tweaked the power supply a bit, so my voltages are like this:
https://app.box.com/s/mx7j4k1fg2bdzbp...

And I used diodes for rectifying, I omitted the rectifying tube, I did not want to bother with it.

Got some used tubes from a friend of mine, hooked it up and fire it away, with two 6L6GC's.




I always wanted a clean amp to be able to use it with a pedal, instead of multichannel hi gain amp, and I think I am on to something! Smile

There are some things that I will try tommorow, for instance the cathode cap for the first ECC83, I will lower it to 22uF, since the 330uF I have now is 30+ years old and probably dry, and I think there is already tons of bass in this circuit, and going lower will maybe help a bit to get rid of the blocking distortion.
Also the coupling caps of 100nF, I will try 22nF, because for my style of playing, there is too much going on in the lows and I think it's giving the output section a bit of a problem with low notes...
Although I build it with the 60s/70s switch, I kinda like the voicing of the 60s (JTM), 70s does make it a bit tighter in bass, though!

Most of the info is in the description of the video!
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