[Xakepa]

Depends very much on the position in the signal path and the rest of the setup. Check my sig.

 

[cotdt]

This one:

http://www.welbornelabs.com/miniamp.htm

 

[Freq Band]

How have y'all been comparing opamps....
What was your method ?
How did you eliminate subjectivity ?

=FB=

 

[audiofil]

I don't think that subjectivity as well as circuit dependency can be eliminated while rolling opamps or doing mods in general.

 

[Joshatdot]

What are all these op-amps for..I know for headphone amps, but which ones?

 

[audiofil]

Opamps cover an immense area of applications starting with power supplies to buffers, I/V converters and so on.
You can read a broad presentation about what they are and what they dohere.

 

[ryssen]

Quote:

What was your method ?

Long time test,with switch back and compare,to find my favorite..

 

[NelsonVandal]

Quote:

Originally Posted by Freq Band /img/forum/go_quote.gif How have y'all been comparing opamps.... What was your method ?

With good stuff: going back and forth, back and forth..., and long time listening to a lot of different recordings. If everything tends to sound the same, it's no good. With not so good stuff: 2 seconds than away (like AD823). I actually gave it some more time, but it only takes 2 seconds to find out it's not for my ears.
Quote:

How did you eliminate subjectivity ?

I wish I had the energy to do blind A-B tests. But I didn't. To do that, you must have two identical amps and some kind of switch box, and I don't. I think long time listening to a lot of different recordings is second best.

 

[Filburt]

.

 

[NelsonVandal]

Filburt, I didn't mean to toss the opamps out of any CDP, I meant the headphone amps. I still can't see why you need an amplifying stage after the CDP. What good could it possibly do? Why reduce the voltage and then amplify it?

 

[ryssen]

Quote:

Why just not toss this opamp away, turn up the volume a bit and enjoy less coloration.

Did you try that?I did,It didn´t sound good at all.
To much midrange,no trebble no bass,why?I don`t know.

 

[Filburt]

Quote:

Originally Posted by NelsonVandal /img/forum/go_quote.gif Filburt, I didn't mean to toss the opamps out of any CDP, I meant the headphone amps. I still can't see why you need an amplifying stage after the CDP. What good could it possibly do? Why reduce the voltage and then amplify it?

Well, you probably at least need a buffer, since the output stage of the CD player may not be suitable for driving the load directly. Many people do do this, but it's not a given that just any buffer stage will outperform any IC op-amp in a given application.

 

[ryssen]

I have a dicrete buffer,didn´t sound good without a opamp..

 

[dsavitsk]

Quote:

Originally Posted by NelsonVandal /img/forum/go_quote.gif Filburt, I didn't mean to toss the opamps out of any CDP, I meant the headphone amps. I still can't see why you need an amplifying stage after the CDP. What good could it possibly do? Why reduce the voltage and then amplify it?

http://www.geocities.com/rjm003.geo/...o/diy_sze.html

http://www.ecp.cc/3sz.html

 

[NelsonVandal]

Quote:

Originally Posted by dsavitsk /img/forum/go_quote.gif http://www.geocities.com/rjm003.geo/...o/diy_sze.html http://www.ecp.cc/3sz.html

Thank you dsavitsk. I've seen that. I agree, that's probably what I want. I just don't know where to get those 2SK21x MOSFETs, and I don't think I'm clever enough to implement IRF510. How would you describe the sound of it?

Ryssen - what buffers did you build, and what cans do you have? Those Sijosae buffers I use don't sound that way. They sound warm and full and without irritating colorations. Not the same slam as AD8397, but that's all artificial to my ears.