Lower mu works just as well when the tail is truly “long”, as in current source to the negative supply long.I would have expected it the other way round - 12SL7 as PI, 12SN7 as voltage amplifiers, due to the SL's much higher µ, from which a LTP would benefit..
Best regards!
Regulation has got to be pretty damn good in that power trafo to keep a whole 180 watts here. My home brew special power trafo drops me to about 420 at full continuous sine wave. 88% regulation, spot on what I get when I buy the darn things and run them to full VA rating. Only real difference in the supply is I used separate 120 and 245 volt windings with two full wave bridges. Got a pair of 800 VA cores out of a solid state amp that’s been decommissioned fixing to get rewound to power a bunch of 21LG6’s. Finally found enough decent compactron sockets!
Power transformer rewinding is fun and satisfying. It feels like cheating on your taxes in a BIG way and getting away with it.
Overall circuit topology isn’t much different, other than there’s a whole EQ chain and more gain in between the first two triodes, with one stage I can starve to add 2HD. I did transformer couple the mic input, though. XLR jack on the rear panel.
Power transformer rewinding is fun and satisfying. It feels like cheating on your taxes in a BIG way and getting away with it.
Overall circuit topology isn’t much different, other than there’s a whole EQ chain and more gain in between the first two triodes, with one stage I can starve to add 2HD. I did transformer couple the mic input, though. XLR jack on the rear panel.