Gallery Photos of My Amp

[gravitylow]

Thanks to Gabi I now have high resolution pictures of my amp in the gallery. I still need to get the Baxandall tone stack preamp working - it only seems to squeal at this point. I think I have a bad 12ax7. It checks out fine in the tube tester but in the curcuit the second triode seems to not be working.

The normal channel REALLY sounds great. I am very impressed with this amp. I am very glad I added a master volume as it allows me to get a great sounding crunchy compressed sound without blowing my ears out.

I'm running it into a Weber Blue Pup and Silver 10 which I am quite happy with - but I haven't heard the amp through anything else.

I made a few modifications to the original design to make things interesting:
I used a dual star ground with the preamp grounds going to one star and the power stuff going to the other. I then connected them together with a 22 awg wire.
I used metal film resistors and poly caps.
I used isolated jacks so everything is isolated from the chassis except at one point at the power star so I could easily isolate the grounds from the chassis..
I put all the components on the turret lug card because I don't like the way the orriginal amp has "flying components" soldered to the pots.
I added a 3h choke similar to a Fender amp with the choke between to 32uf caps just after the standby switch. I don't really have a good reason for this except that I though it might give the power supply a little more filtering and punch. All the other amps I've looked at had one as well.
I brought the filiment windings to a terminal strip and stared them to the tubes. I did this mostly because I had a lot of difficulty running a serial connection with 18awg to all the tubes. Also, since I am using the Mercurey Mag 20 watt transformers there is no second filiment winding for the rectifier tube so it is tied to all the other filiments.

Feel free to comment or critcize.
Wayne

[markh]

Nice-looking build, Wayne. That is one loooong board. You might want to try decoupling (adding an R and C in the P.S. line) the two stages around the baxandall tone controls.

Also try swapping the 12AX7s around in different positions to eliminate the tube as a problem source. The PI position is least critical about microphonics.

--mark

[gravitylow]

The decoupling is an excellent idea - if only it was mine .
When I get it back on the bench I will give it a try. I did try tube swapping but I got inconsistant results - the first time it seemed to fix the problem and the second time it didn't work. Right now I'm having too much fun playing the amp to put it back on the bench.

Thanks for the input,
Wayne