I didn't test it with any measurement gear.
I'm not sure why. It's very hard to make perfect audio gear without having proper measurement tools, and tweaking several prototypes until the measured results are optimized.
I would suggest you check out Samuel Groner's work, he has excellent independent test of many opamps, including some mentioned here.
http://www.nanovolt.ch/resources/ic_opamps/pdf/opamp_distortion.pdf
Alan
http://www.nanovolt.ch/resources/ic_opamps/pdf/opamp_distortion.pdf
Alan
It would be great to get the 994-enc-ticha working properly also with Boggit's input buffer. Espesially if it could be worked out without modding the inputboard, but with a special dip8 adapter. Unfortunately i am not kind of person who can debug such problems.
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I know you did not test them I just wondered if you could see any obvious problems causing the extra noise in your system. I have both boards myself but I am not an electronics engineer like yourself.
It's likely Johnson noise from the resistors. But I'm not an electronics engineer either. When I want things like that built, I hire electronic engineers. And if it doesn't meet spec, they don't get paid 🙂
...well if that is the case, Resistors...they shouldn't be hard to swap out - the Vishay ZFOIL are the best one can get according to John Westlake (but not cheap @£10-20 each) if they can be had at those values!?
This was the Rep I was speaking with last year about Z-Foil
Elida
Texas Components Corporation
Customer Service/Sales
P: 713-468-3882
F: 713-461-2098
elida@texascomponents.com
www.texascomponents.com
Elida
Texas Components Corporation
Customer Service/Sales
P: 713-468-3882
F: 713-461-2098
elida@texascomponents.com
www.texascomponents.com
The problem is that Johnson noise (properly "Johnson-Nyquist noise" (yes, that Nyquist) is pure thermal noise. There are no "better" or "worse" resistors in that respect. Johnson noise *only* depends on the absolute temperature, not any other property of the resistor.
So in terms of Johnson noise, the Vishay resistor is no better than the cheapest no-brand resistor you can find.
Another reminder that just using expensive, "audiophile-grade" components doesn't necessarily improve anything (at least objectively).
I am trying to reconcile that statement with this:
I am assuming that when you wrote "I have tested all 3 already" you meant "tried" rather than "tested"?
If I was releasing a commercial amp using them it would come with the same spec sheet the the NC 500's come with, but with the buffers in place.
Not sure I am any wiser. Did you or did you not test the 3 opamps? And what does "test" mean in that context?
Just trying to clarify/understand what you are saying. So, which is it,
a) you have tested the opamps, but you are not sharing the results with us (because you are not releasing a commercial product), or,
b) you have not tested the opamps
Well I did share pictures testing them. I'm not sure why you are so deeply concerned with this?
OK, let me rephrase my question by asking if you *measured* them? or what do you mean by "testing"?
I am not "deeply concerned", just intrigued by your admirable effort at trying to avoid actually answering 🙂
If you don't want to answer, just say "I'd rather not answer".
I've already explained my testing procedures. Look back in the archives. Although I'm not sure what was deleted because lots is missing now.
Indeed, seems it was deleted or moved elsewhere. So would it be too much effort to repeat it again?