Phil Budgell wrote:

I recently purchased one of these little amps and was wondering what I
should do in terms of mods if any. I am not at all familiar with tubes so I
really can't say if I am getting good sound right now or not. Any help would
be greatly appreciated.

Nice small amp within its capabilities, an actual 15 or so watts per
channel. The EL84/6BQ5/7189 output tube is good-sounding but they run
hot. See that the ones you have are up to snuff, and clean up the
switches and controls with Cramolin or DeOxit-5.

Amp could benefit from beefing up power supply capacitance, and higher
quality film capacitors for interstage coupling.

The preamp tubes need to be checked too. The 7199 drivers are now being
made in Russia again after years of unavailability, so if one is bad you
don't have to rewire the socket for a 6AN8 or 6GH8; but they don't go
bad very often. If yours are working and they don't look milky or
cloudy they are likely OK. If they are weak or bad, Antique Electronics
has them.

-GP