What good does it serve for other readers to describe what only you can perceive in your own unique setting?
One can speculate till the cows come home but that won't do anyone any good except for marketing literature.
What process revealed that known artifact? Without a clear description, you are just inviting more complaints.
I guess you missed my joke: the piano used in the recording was actually a Bösendorfer
Thanks... makes me think that all records should be forced to state "NOT A STEINWAY" if that is true (for the Steinway fanatics).
Can you guarantee that the fundamental spectrum component in an FFT as being referenced to 0dB is undistorted?
Not good enough... nothing to do with audibility...
It's how much of distortion is audible or not.
Can it be guaranteed that, in only the observation of an FFT spectrum, whereupon the fundamental component at 0dB (being mathematically perfect) can itself still be considered a contributor of distortion?
In-band IMD is not inherent to NOS. It only seems to be an issue in intellectual contemplation, and which depends on the design of the post D/A circuitry. I’m aware of no logical argument for why NOS is inferior to OS for the purpose of humanly audible music playback, where the ear acts as a biological low-pass reconstruction filter, effectively removing the image bands. As I had observed earlier, the top 5 DACs of the post #1 listening tests ALL featuring NOS, while the remaining two at the bottom feature integrated OS. Which argues that, at worst NOS does no subjective harm, and at best is a significant element to the subjective performance those top ranking DACs. It remains unanswered in the test, to what degree NOS is responsible for the sound among the top tier group. Just to make it clear, I don’t see the problem as OS, in itself. For it is, in mathematical sampling theory, perfect in digital signal reconstruction. Instead, I see the problem as the inadequate practical implementation of the integrated interpolation-filters within a great many monolithic DACs chips. External OS via s/w on PC, for example, can subjectively perform at a level with NOS.
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No, but the higher the ultrasonic components the higher the IMD products of ultrasonic components.
Sure, if the lower ultrasonic images of NOS were a problem in the first place. Which, they evidently weren’t in those five NOS DACs which were all subjectively judged as surpassing both of the OS DACs.
As "relevant" do you mean one that doesn't threaten to "deny thy faith"?
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My comments were not related to OP's listening test. Sure you can argue that the IMD products caused by NOS were not a problem for these listeners. Who knows, they may prefer distortions and other non-linearities. Others may feel different.
Since you have a difficult time understanding the concept, the following are some examples of relevant questions which I still haven't seen the answer.
1)
Relevant question:
2)
Relevant question:
What "concept"? No difficulties here. Are you suggesting that answers to your so called "relevant" questions are ones threatening to "deny thy faith"?
The -85 dB we discussed earlier came from a transimpedance amplifier without overall feedback, so chances are it is low-order distortion.
Regarding undithered quantization, the RMS level of all quantization distortion products together stays at about the same level as the desired signal drops, so it gets worse with respect to the desired signal; -98 dB at 0 dBFS becomes -58 dB at -40 dBFS. It also gets less noise-like with dropping level, that is, the chances of getting a spectrum that doesn't resemble noise at all gets worse (1). It is still so soft that it is questionable if it will be heard under domestic circumstances, but I'd rather avoid it.
(1) It's not a completely fair comparison, but when I was 17, I built a circuit that could store a few seconds of sound in 1 Mbit of DRAM, using an undithered first-order delta modulator to digitize the signal. I use it as a doorbell with programmable sound. It sounds pretty bad at any level, but it clearly gets worse when you record very soft sounds with it.
It's a good test. An old trick to hide idle tone issues in sigma-delta modulators is to add a small DC offset that is large enough to shift them well outside the audio band. Play back an opposite DC offset and they shift right back into the audio band.
The chaotic mode of my valve DAC (which is a sigma-delta DAC) has no audible tones, but non-stationary noise that depends on DC offset. For very small DC input signals, you hear the noise varying with a speed that depends on the offset. It is due to a combination of the behaviour of the chaotic modulator and imperfect settling of the DAC. I'm in good company, as Lars Risbo had similar issues with the chaotic sigma-delta DACs of his PhD thesis.
While that is true. What I’m really getting at is, that NOS may be a very key factor in the top five DAC rankings. It certainly jumps out as a common feature across all the favored DACs in this evaluation. There's no way to tell via the result details shown, of course, without further experimentation.
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