Thanks Alexsandr!
I do indeed appreciate your help.
Over the past week I had dilemmas whether to proceed with this project due to lack of MJL21193/MJL21194. Currently, it is virtually impossible to purchase these transistor pairs from reputable supplier - there are just few MJL21193 left whilst lead times for the complementary are prohibitively long. I have also considered using TO-3 MJ variants, but in the recent past I had bad experience with ON-Semi TO-3 devices. Namely, I have more than a dozen of brand new MJ15003/04 which are useless: their hFEs are in two groups differing by much more than 50%. On the other hand, I have almost perfectly matched 2SA1943/2SC5200 pairs, Also NJW3281G/1302G devices match just fine. I will abandon the path involving MJL21193/MJL21194 because I suspect none of them would ever match fine.
As far as I understand, Chalky is also experimenting with "faster" devices due to this problem. I intend to follow his path. Could be fun.
Don't worry Alexsander.
I plan even to make a PSU larger, with more, large, capacitance. Amplidude did the right thing: he uses an array of massive capacitors to provide enough power when needed. Amplifier will take power from it as much as it neededs. In this case more is better.
Of course. I will use also the PSU board, with everything you need integrated: Soft-start and separate speaker protection for both chanels are precious.
Only one thing regarding the PSU worries me: I prefer dual-mono where both sides are separated, except the input grounds. This is the guarantee for easily achieving a totally silent amplifier. That's what we all want: to hear nothing when nothing is at the input.
Hello hschier,
Have you tried a 2sc5200/2sa1943 pairs? Are there any problems with "faster" devices?
Hello Sensation45,
Where have you purchased 2sc3421 2sa1358?
I have purshased INCHANGE 2sc3421 2sa1358 for my previous project from Reichelt (Germany). These were good transistors.
