Tube-I-zator SRPP DAC I/V-Stage circuit discussions

[gabanyayaya]

Oliver

What if the DAC is V-out which usen a single tube, dual triod...?

[SY]

More fundamental question- why an SRPP in the first place? You're throwing away linearity and S/N to achieve.... what?

[dvb-projekt]

Originally Posted by SY

More fundamental question- why an SRPP in the first place? You're throwing away linearity and S/N to achieve.... what?

As i wrote, i had insert this stage in my DAC project and being absolute satisfied of the sound.
Because i am not a developer, i could only state about the sound performance and not to any technical data from a SRPP or other stages.
BTW, for me the only interesting thing.
We could discuss so much about linearity, NonOverSapling yes or no etc., but this is not the part of this thread.

Here i would like to focus question around this circuit.

Originally Posted by gabanyayaya

Oliver

What if the DAC is V-out which usen a single tube, dual triod...?

I don´t see any problem to integrate this circuit after a V-Out DAC.
You must only insert a small capacitor around 0,47µF between the V-Out DAC and the input of the PCB.

[Koifarm]

Here is a little excel application where you can calculate the output impedance of several tubes in a srpp stage.

http://www.ict-net.net/tube.xls

[SY]

Here i would like to focus question around this circuit.

Well, my question was specifically about this circuit. So I'll ask again- since you're decreasing linearity and degrading signal-to-noise compared to a simple voltage amplifier, and at the same time you've increased parts count and complexity, what is the advantage of this circuit? Unless the motivation for this topology is explained, how can anyone suggest improvements?

[dvb-projekt]

Originally Posted by SY

...what is the advantage of this circuit? Unless the motivation for this topology is explained, how can anyone suggest improvements?

i think the advantages of the circuit to normal standard SS output stages in most of all CD-Players and DAC´s you could read allover the net, also in this forum.

If you would like, i could give you the link

[SY]

Please do.

But... my question was not advantages over a poorly-designed SS output stage, my question was the advantage over a much simpler, properly designed common-cathode voltage amplifier stage (or, for that matter, a well-designed simple SS output stage). SRPP is useful for large signal swing applications (which this certainly isn't), but trades off linearity and gain to achieve that. So, for the extra parts count and complexity, the performance for the 2V or so of a digital source would seem to be degraded. If you can point me to data to the contrary, I'd be grateful.

[dvb-projekt]

HERE you could read the experiances from other members.

For you again, i am not a developer to answer questions about different stage technics.
I opened this thread around the SRPP Tube-I-zator circuit.
For any questions beyond, there are threads like the linked thread, where you get answers to your question.

Regards,
Oliver

[danzup]

Originally Posted by SY

Well, my question was specifically about this circuit. So I'll ask again- since you're decreasing linearity and degrading signal-to-noise compared to a simple voltage amplifier, and at the same time you've increased parts count and complexity, what is the advantage of this circuit? Unless the motivation for this topology is explained, how can anyone suggest improvements?

Sy : I think the improvements is in sound and it is only in the ears and not in measurements !
( As a friend of mine say : I do not care about measurements and benchmarks and oscilloscope but I always care about what I hear : the music ! )
Some time we tend to be to precise and academic .....

[Karsten Sømand]

I really do understand SY´s questions, but I don´t think I fully understand the answers?.

Could the reason for the SRPP be that it is (very close to?) a circuit used by Audio Note? AFAIK Audio Note are extremely careful when designing circuits, and I know that Mr. Fikus is a big fan of Audio Note. Mr. Fikus has made a lot of experiments and maybe this type of tube circuit is the best for his ears?

However, in the other thread which Oliver links to, DIYAudio member regal (#48) shows a SET stage which he claims to be superior to the SRPP circuit. Might be something like this SY has in mind?

Have anybody tried both topologies against each other?

Karsten