This one has 4 individual bias pots and 10R cathode resistors. The SE in the name is misleading and they do make an SE amp (confusingly). This one is P-P with two pairs of triode-strapped KT88s.
Could not locate any manual online, so you may have to contact the company. In any case, what voltage do you measre across the 10R now?
At the moment I've evened it out to 500mv. It had previously been messed up and randomly played around with. Plate voltage is 420v. It looks good on the scope and sounds OK. Output is a little shy of 28W per channel at the point of clipping and there's nice symmetry between both channels.
50mA is probably not too far from where it should be. But to make sure, you would need to get the word directly from Triode, it would be nice to know what the primary impedance of the output transformer is also.
I received a reply from Triode this morning - they use 30mA, which is cooler than I was expecting.
Yes, that's very cold bias, with hardly any Class A output. I'd leave it at 50mA as you already have done.
With 30mA there's a crossover notch when the volume is turned up to 3/4 and signal level of 0.7v RMS/1khz sine input that isn't there with the hotter bias. It's outside of normal listening levels and maybe something that wouldn't therefore be noticed unless you were scoping the output. It shows that the amp is only just into class A with the factory setting. I guess the intention is to run the valves as cool as possible to both minimize noise and extend lifespan.
TRV 88
Hi Mike, just picked up a Triode TRV 88SER and saw this old post. Did you ever locate a schematic for this amp?
Hi Mike, just picked up a Triode TRV 88SER and saw this old post. Did you ever locate a schematic for this amp?
I just saw you sent me a PM. Sorry, I didn't find one and spent a good deal of time looking around. You could try emailing the factory just in case they will let you have a copy, but I had no such luck.