5F2A-with-6L6 build

Keefy

Well I think I've worked out why my reverb pedal seems so noisy through this amp.

Yes it's a bright amp (even with a different speaker, and regardless of the valves used), but it's also massively gainy, and actually runs out of headroom at 9 o'clock on the volume dial (i.e. about 2 on a scale of 1-10) when running a 6V6. I followed the original 5F2A layout to the extent of fitting a linear pot for the volume control. In hindsight, it might have been better to use a log pot if I'd wanted the 'clean' section of the volume sweep to be broader. With the amp and guitar volumes set to give a harmonically rich sound that is highly sensitive to picking strength, the amp's small-signal gain is so high that it is amplifying low-level hiss from the reverb pedal that is all but inaudible in the way I normally use it, i.e. into a 5E3 (regular or micro).

It's a monster of a little amp, and well worth the modest outlay on parts, many of which were recycled. I'm not sure what I'll use it for yet, but hey, that's another successful build under my belt!

EDIT: NOTE TO SELF - Of course it's bright at low volume settings you doofus, there's a 500pF bright cap in the tone/volume circuit! Might try a 12AY7 in V1 to allow me to turn the volume higher without hitting the buffers.

Keefy

Yup, 12AY7 in V1 did the trick - I can now turn the volume to 5 (12 o'clock) to get harmonically rich edge-of-breakup tones from the 6V6. Result!