Stephen,
I'm not switching channels; the inputs of the two channels are bridged. If I were to do it again, I would build a single channel version with only the pentode section. Both channels sound great, but the pentode section is simpler, and has a bit of sparkle that the triode section doesn't have.
I built it point to point using terminal strips. i laid the strips out like a tagboard, which makes it very easy to cut and try components.
Here's an interior shot:
From the shot above, it should be clear that 12 x 10 is too small of a chassis for such an amp. More than once I considered starting over with a bigger box, but instead I promised that I'd not make the same mistake next time.
It's a bit of a spaghetti bowl, but the hum is tolerable and gets swamped by the hum from most pickups.
The schematic is essentially the same as a DC30 with a few differences:
-only 2 EL84's in the output section. More like a Lightning output.
-6AK5 instead of EF86. This 7-pin signal pentode sounds great and is way cheap.
-Instead of a 6-position switch tone control for the pentode channel, I used a spdt switch and chose 2 caps that sounded best to me. Right now, that's 330pf and 1000pf. That could change any minute, though. The switch is marked "brilliant" and "sinister".
-5AV4 instead of 5AR4 rectifier, a 5AR4 would drop in. The difference in sound escapes me, however, and NOS 5AV4's are inexpensive.
-Tone control caps and bright caps are different. I'm still experimenting with these.
I'll draw up an as-built schematic once things settle in.
I'll have some mp3's done by midweek.
-n
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