Studio Reference Amplifier

[jlester87]

Originally Posted by apexaudio

There is no mosfets on SR200

My mistake, I was thinking about HV350 which uses mosfets. BTW, viki_v2 used 2sc2922-2sa1216, will it increase the power capability of the amplifier as well since it is rated @200w per pair? Thanks

[carlmart]

Originally Posted by apexaudio

No, use buffer preamp from post #177,

I think it's a shame to use such expensive parts and then put a large (electrolytic) capacitor at the output to block DC offset.

Why not try something simpler, like this:

DAC output stage

[apexaudio]

Originally Posted by carlmart

I think it's a shame to use such expensive parts and then put a large (electrolytic) capacitor at the output to block DC offset.

Why not try something simpler, like this:

DAC output stage

Why not try something like this:
http://www.passdiy.com/pdf/B1%20Buffer%20Preamp.pdf

[carlmart]

That's much better, but it still needs an output capacitor.

As you also have a 10uF capacitor at the SR100/SR200 input, why not integrate that Pass preamp to it?

Why not eliminate R1, R2, C1 and R3 from the amp, or C101, R104 and R105 from the buffer? That is: leave just one 10uF cap and pick a top quality film type for it.

[apexaudio]

Originally Posted by carlmart

That's much better, but it still needs an output capacitor.

As you also have a 10uF capacitor at the SR100/SR200 input, why not integrate that Pass preamp to it?

Why not eliminate R1, R2, C1 and R3 from the amp, or C101, R104 and R105 from the buffer? That is: leave just one 10uF cap and pick a top quality film type for it.

You can use 'REF' (DC) input ( schematic in post #50)...Studio Reference Amplifier

[carlmart]

Originally Posted by apexaudio

You can use 'REF' (DC) input ( schematic in post #50)...Studio Reference Amplifier

Indeed, going into REF will bypass all those parts and you only use the buffer output cap. Nice call.

[apexaudio]

Originally Posted by jlester87

My mistake, I was thinking about HV350 which uses mosfets. BTW, viki_v2 used 2sc2922-2sa1216, will it increase the power capability of the amplifier as well since it is rated @200w per pair? Thanks

No, with same rail voltage and load amp output power will be same.
Regards

[viki_v2]

Mile,
Today I tested both the amps properly connecting to my floor standers,
Checked both channels Individually for difference, Speaker with Amp having 2sc2922 is giving better performance in comparison to 2sc5200. Even with 2 pairs of transistors it out performs amp with 3 pairs of transistors in bass section at same volumes.

[carlmart]

Is there any US supplier that stocks Sanken transistors like the 2sc2922? Who does?

[apexaudio]

Originally Posted by viki_v2

Mile,
Today I tested both the amps properly connecting to my floor standers,
Checked both channels Individually for difference, Speaker with Amp having 2sc2922 is giving better performance in comparison to 2sc5200. Even with 2 pairs of transistors it out performs amp with 3 pairs of transistors in bass section at same volumes.

I prefer SanKen, but Toshiba is easy available and I want to share high-end diy amp useing standard parts.