- Thread Starter
- #301
Absolutely. With one caveat. I get to pick the amplifiers under test. I say this because with some amplifiers, there is no detectable difference. With others, there are marked sonic signatures. And the test will be done at our lab / studio using our blinded AB technique and reference chain. One neutral observer attending.
Amir, I'm not sure why you think this test will fail. You've already presented evidence of an AES amplifier listening study in which at least some ABX differences were in fact repeatably detected by blinded listeners. This is all the evidence you should need. The answer is in your lap. Differences were detected. Mission accomplished, Done. Science wins. The premise that "IC differences cannot be detected" was proven invalid by one lone peer-reviewed AB test. Why do you continue to insist otherwise in the face of peer-reviewed evidence?
What would be even more instructive is to put together 2 or 3 top-end -130EIN / -120dBTHD industry micamps and do some DPA-based recording of difficult sources (rattling keys, bell tree, etc.), align the tracks on AB test DAW (Sequoia), and do the same blinded comparison testing. Easily detected differences, likely due to input capacitor transient behavior rather than periodic / harmonic distortions of the active stages.
In fact, we recently did a similar test for the most advanced micamp we've ever developed (premiering at NAMM in 2 weeks!). The test was to AB the sonic signature of various candidate input capacitors. At least two or three were rejected almost immediately. 10/10. A number were in the middle, OK but iffy. And two parts were clearly more transparent to the source, at least 8/10. We are using those qualified parts in the new product. (keep in mind, none of the capacitors under test impacted the baseline noise or THD performance of the signal path -- the source of detectable distortion is something other than THD -- which is another conversation that goes to root of why -120dB THD does not "guarantee transparency")
Anyway, if you let me pick the amplifiers myself, the AB differences will be even more pronounced than those detectable IC's in the AES Journal test. It's sort of not fair (to you).
But I'm puzzled about the $1,000 reward. If I do get a reward, I'll donate it back to the ASR community.
Now to the more important issue.
None of this is about me. Testing my AB chain, claims, ears ... is a silly side-show. Audio claims aren't settled by one test on one person. Rather, it takes a large population of samples and trials and participants to achieve peer-review acceptance (like the AES paper you highlighted). But you know that.
So, I'll make this deal. If I can score minimum 8/10 on a simple blinded comparison of two amplifiers, you will make my suggested changes to the ASR community site.
Night night. I'll address all your other recent comments tomorrow.
...and there are the conditions...........
No chance.
The test is to compare op amps, similar performing op amps which you said you could hear the difference between.
Test circuit to be designed collectively by the various experts here (or existing design approved). Then tested on Amirs AP.
Tested using a collectively agreed technique, not yours (unless of course its seen as OK by the collective).
Your listening room/equipment - OK but it has to be fully detailed and OKd by the collective.
You need to be able to identify which op amp is which to statistically significant levels.
The test is not to compare complete mic amp designs.
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