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So it's a hole? Care to elaborate?
Figure of speech? The industry at large will probably not explore any other solutions.
So it's a hole? Care to elaborate?
Figure of speech? The industry at large will probably not explore any other solutions.
The biggest objective detraction I have seen regarding delta-sigma converters is the potential for noise modulation (hand-wavingly, the noise floor changing with the signal). My impression is that issue, like earlier issues with tones and other artifacts, has been solved with modern designs using dither (noise decorrelation), higher-order and multibit loops, and better filters. Don't know for sure, though, but Amir's measurements don't seem to show any problems... I have lost touch with my old teacher and mentor that helped me many years ago (Dr. Gabor Temes) but imagine Scott and others could answer (at length). My delta-sigma experience (ADC and DAC) was at RF and used much simpler designs than used at audio frequencies.
Modern (audio) delta-sigma converters use upsampling to push modulation noise away from the audio frequency band and use LPF on analog circuits to filter it.
In fact, this has been done from TDA1541 and even earlier DAC chip architectures (though not necessarily a delta-sigma architecture)
The 9018 series did have the noise floor modulation issue. The noise floor is modulated by the signal. This phenomenon is also shown by Okto research hear in ASR. (I can confirm this too). The following generations have other modulation issues which are solved by external design. Such issues have never been found on any chip (that I'm aware of) from AKM, TI or, Cirrus logic.The biggest objective detraction I have seen regarding delta-sigma converters is the potential for noise modulation (hand-wavingly, the noise floor changing with the signal). My impression is that issue, like earlier issues with tones and other artifacts, has been solved with modern designs using dither (noise decorrelation), higher-order and multibit loops, and better filters. Don't know for sure, though, but Amir's measurements don't seem to show any problems... I have lost touch with my old teacher and mentor that helped me many years ago (Dr. Gabor Temes) but imagine Scott and others could answer (at length). My delta-sigma experience (ADC and DAC) was at RF and used much simpler designs than used at audio frequencies.
but imagine Scott and others could answer (at length)..
And someone can make "true-SAR" vinil rip records via AP HF channel (1.25MHz)?
For compare with DS-rip via LF-channel (90 kHz max).
.
I want to see comparison Holo vs. Mark Levinson 360s (PCM1704):
https://www.audiosciencereview.com/...ts-of-schiit-yggdrasil-v2-dac.3607/post-86611
Delta-sigma topping dx7 generate strange 2 sidebands.
And someone can make "true-SAR" vinil rip records via AP HF channel (1.25MHz)?
For compare with DS-rip via LF-channel (90 kHz max).
FYI comments about ADC architecture:
"Delta sigma's suppose to be a cheap alternative of the expensive and more advanced SARs, this article is sponsored by Texas Instruments and of course they aren't great at SARs, SAR is the first choice of the experienced professionals, everything else is cheap advertise"
https://www.electronicdesign.com/adc/what-s-difference-between-sar-and-delta-sigma-adcs
R2R DACs and SAR ADCs have a guaranteed settling time, deltasigma - not.
Listening to the benefits of R2R DACs is difficult on phonograms (records) corrupted by delta-sigma processing.Vinyl ripping would not be my choice
Listening to the benefits of R2R DACs is difficult on phonograms (records) corrupted by delta-sigma processing.
Old digital recordings (before 1990-1995) are SAR frequently.
corrupted by delta-sigma processing.
(even though audibility is not a valid standard by which to judge DACs or ADCs)
"It is not a new technology now, and has been well tested over the years."Literally the first reply:
This is a commemorative prototype
MSB Select II DAC (3072 kHz/24 bit PCM R2R) is new, have 2000V/us output speed.