Studio Reference Amplifier

[mihailo]

Leonatax, you can use BC557,BC556,BC560 and BC546,BC547,BC550. Just dont use BC548/BC558. They are only 30V limit. There are also some 2SC/2SA, that can be used.
Regards

[leonatax]

Thanks a lot

[mihailo]

2SC1815/2SA1015 can be used instead of BC546/BC556, but look pin position.
Regards

[carlmart]

Originally Posted by mihailo

Leonatax, you can use BC557,BC556,BC560 and BC546,BC547,BC550. Just dont use BC548/BC558. They are only 30V limit. There are also some 2SC/2SA, that can be used.

Voltage limit will depend on the position the transistors are in.

For Q1-Q2 you can use better, lower voltage transistors, even dual types if you can find them. Like MAT01 and MAT02.

[apexaudio]

There is no any voltage limit for replace BC550/560 transistors. BC550/560 works in cascode 15V is maximum DC voltage for input pair, and only 1,5V in cascode VAS.

[carlmart]

Originally Posted by apexaudio

There is no any voltage limit for replace BC550/560 transistors. BC550/560 works in cascode 15V is maximum DC voltage for input pair, and only 1,5V in cascode VAS.

Yes, of course. There are 15v zener regulators up and below.

Just curious. Did you try a better regulator to replace the zener ones?

[apexaudio]

Originally Posted by carlmart

Yes, of course. There are 15v zener regulators up and below.

Just curious. Did you try a better regulator to replace the zener ones?

No, zener regulators is simple shunt regulators and work good

[apexaudio]

Originally Posted by apexaudio

This is my amp from 80', modular drivers and protect pcb only caps is too big to be fit on amplifier motherboard. I considering to use this design for 'Studio Reference Amp'.

I find schematic of this old amp from '80.

[leonatax]

injoy my type of pcb

[leonatax]

enjoy my pcb