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New 28-bit DAC coming out.

The actual DA convertor output is stepped, i.e. it contains above-nyquist ultrasonic frequencies which must be removed (the steps "smoothed out") by the analog reconstruction filter. For 44.1 the nyquist is 22kHz - it's very hard to make an analog filter so steep to keep 20kHz and "completely" eliminate 22kHz. So e.g. upsampling 8x moves the nyquist to 176kHz - the analog reconstruction filter now must filter out everything above 176kHz, while keeping 20kHz - much easier to do.

Oversampling on the ADC side is done for the very same reason - the input analog filter before the ADC (again "completely" eliminating from nyquist up) does not need to be so steep because the AD conversion nyquist is moved much higher by the oversampling.
Is this why high sample rate music files might sound differentially better on DACs with less effectively implemented filters, while red book and even mp3/4 or ACC files can sound pretty great on DACs with more sophisticated/better implementation of filtering?
 
Is this why high sample rate music files might sound differentially better on DACs with less effectively implemented filters, while red book and even mp3/4 or ACC files can sound pretty great on DACs with more sophisticated/better implementation of filtering?
First you'd need to demonstrate the audible difference you are describing actually exists - rather than being bias based.

Then (if I am understanding your question) - No, because @phoman is talking about the analogue reconstruction filter. Upsampling allows the nyquist filter for 44.1kHz files to be done digitally as part of the upsampling process. Much easier to get sharp fast filters digitally than it is in analogue.

Then for both high res files, and redbook files the analogue filter is the same - and only needs to filter out higher (upsampled) sampling frequencies.
 
Most LPs you listen to have been digitally processed before being pressed onto vinyl. This idea that "digital sounds worse" or all the other silly ideas about "fatigue" and whatnot are absolute hore-s-h-i-t. There is no such thing and only people clueless about audio engineering try to perpetuate this stuff.
OK, maybe it’s only gopher s-h-i-t. I have at least 100 titles on vinyl that were recorded, produced and pressed before 1978, and very likely have zero digital elements in the recording chain. Some of my other boutique titles are much newer and claim to be recorded using 100% analog/tube gear from the microphone to vinyl, and I also own some MoFi reissues that I presumed to be 100% analog but turn out to have a digital step their production (they sound glorious in spite or because of this).

As both my analog and digital front ends improve (and implementation of digital to audio conversion in general improves), I notice that the sound quality of the two sources is converging in my system, at least for some recordings. That said, I notice records pressed from the late 1950s and early 1960 have a certain quality to their sound that is warmer - perhaps I am confusing the distortion of tube electronics used in recording and production with the differing effects of analog or digital mechanisms of extracting the sound from a disk or a file. But, digital Red Book file reissues of these recordings at least in some instances don’t have the same “warmth”. YMMV

kn
 
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There is no loss of precision for signals below Nyqust frequency. Please note, that if we talk about signal with frequency, we mean periodic wave, which consist of multiple samples. There is no shift of signal caused by error of a single sample. Actually with a proper dithering, quantization error is turned into noise. And you can hear periodic signals below noise level.
I was ignoring dithering, that's true. The linked site which was bein discussed also does so, as far as I can see. So with that, the error will be zero on average and uncorelated but not zero for individual samples, right?

I did also talk about multiple "samples" in my post: If you have a systematic error at each sample point of a periodic wave - which you do if you discretize it at a fixed bit depth without dithering - this should lead to small systematic errors in the reconstructed waveform. These errors could result in a small time shift, or I imagine they could also result in a tiny frequency modulation - but the error must go somewhere if it is systematic.
 
OK, maybe it’s only gopher s-h-i-t. I have at least 100 titles on vinyl that were recorded, produced and pressed before 1978, and very likely have zero digital elements in the recording chain. Some of my other boutique titles are much newer and claim to be recorded using 100% analog/tube gear from the microphone to vinyl, and I also own some MoFi reissues that I presumed to be 100% analog but turn out to have a digital step their production (they sound glorious in spite or because of this).

kn
Those Mofi digital steps are probably DSD masters and are going to be identical to the analog tapes they were archived from. I don't have an issue with digital recording or mastering as long as it isn't highly compressed. With some modern records the most important part about them saying all analog is they aren't compressing the audio during mastering. There are some amazing sounding digital albums though. Herb Alpert's Rise and Donald Fagan's Nightfly were recorded on 3M PCM digital equipment from the late 70s and those albums sounded amazing on the original vinyl records or the later 80's CDs.
 
It's also not totally clear if a time difference of 10 µs would be less or more audible at 20 Hz than at the frequencies where the relevant experiment was conducted (I think it was 300 and 3600 Hz).
Aren't such low frequencies considered to be non-localizable?
 
Time difference between what 2 things?
You can check the sources, various stimuli were tested: Gaps in playback, double-impulses, time differences between the ears for the same sound and so on. All with different outcomes. That's also why it is difficult to determine which stimulus would best apply in a case like this where some small shift in real music is being proposed.
 
I guess my question is, what timing differences (between what things) are you suggesting 24bits is better at than 16?
 
I guess my question is, what timing differences (between what things) are you suggesting 24bits is better at than 16?
If tmin in the equation in the link provided by @RandomEar earlier in this thread is demonstrably related to our current understanding of the lower limit of the sensitivity of human hearing for timing errors, then the answer is “yes”. For low frequencies and low amplitude signals, tmin approaches 10us which is near the limit of human hearing to differentiate timing errors, so signals in this range are certainly not orders of magnitude below our ability to detect timing differences.

Relating to the Imersiv D1 DAC which is the original topic of this thread, it is possible that significantly lowering the noise floor for low level signals in general could differentially benefit how we perceive higher bit rate recordings, at least for low frequency material.

kn
 
If tmin in the equation in the link provided by @RandomEar earlier in this thread is demonstrably related to our current understanding of the lower limit of the sensitivity of human hearing for timing errors, then the answer is “yes”. For low frequencies and low amplitude signals, tmin approaches 10us which is near the limit of human hearing to differentiate timing errors, so signals in this range are certainly not orders of magnitude below our ability to detect timing differences.

Relating to the Imersiv D1 DAC which is the original topic of this thread, it is possible that significantly lowering the noise floor for low level signals in general could differentially benefit how we perceive higher bit rate recordings, at least for low frequency material.

kn
As pointed out by @popej , the calculation I linked and my own example disregarded dithering, which is standard in music mastering. So the actual error is (on average) way smaller than that theoretical boundary without dithering.

And below I think around 80 Hz, it's commonly assumed that we can't locate sound sources as mentioned by @danadam . Locating sounds is based on perceiving time phase or differences for the arrival of the sound waves at each ear. Based on that, I think we can assume that the ear can't perceive differences as small as 10 µs at 20 Hz and probably not below 80 Hz. It's not a trivial topic and there's lots of things to consider.
 
As pointed out by @popej , the calculation I linked and my own example disregarded dithering, which is standard in music mastering. So the actual error is (on average) way smaller than that theoretical boundary without dithering.

And below I think around 80 Hz, it's commonly assumed that we can't locate sound sources as mentioned by @danadam . Locating sounds is based on perceiving time phase or differences for the arrival of the sound waves at each ear. Based on that, I think we can assume that the ear can't perceive differences as small as 10 µs at 20 Hz and probably not below 80 Hz. It's not a trivial topic and there's lots of things to consider.
Of course, which is why LFE for home theater is provided in mono and generally no one complains. Nevertheless, bass below 80Hz in stereo recordings “sounds better” to me and other listeners on some recordings played back through some systems and in some formats. More clarity, appropriate decay, etc are clearly discernible as “better”.

I wonder if you are confusing “Locating sounds” with listener capacity to identify differences in pitch, tone and accuracy in representing the dynamics or speed at which a bass note starts and stops”? The ability to hear such changes requires appropriate implementation of low frequency capable transducers and enough power to control them - most certainly one or more good subwoofers(s). And even applying DSP to improve in-room performance for notoriously difficult to accurately represent low frequencies is only as good as the information contained in the digital or digitized analog recording.

If there is any uncertainty related to the accuracy of implementation for the 16/44.1 file standard with respect to low level bass reproduction - for example, does dithering erase any perceivable issues - the definitive test would be an ABX blind listening test with Red Book and HiRes files of the same well-recorded music containing low level (amplitude) bass notes originally captured at high bit rate and sampling frequencies and employing playback gear in a listening space capable of accurate reproduction. This effort can get in line with the many demands for such surveys that have been made in this thread related to the claims about the Imersiv D1 performance, let alone on this site as a whole.

kn
 
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No confusion. Locating sounds works by time and phase differences between the ears, as well as level differences, reflections and spectral changes. My argument: If you can't locate sounds below 80 Hz then all those cues, including time differences, are not enough to be differentiated at those frequencies. If multiple cues are inaudible, then a single one of them (only time difference) must be inaudible too - up to a certain threshold, of course.

Quick calculation: At the speed of sound, the time difference between two ears 0.25 m apart would be around 730 μs. So quite a bit larger than difference we were talking about before. But maybe this is a bit too simplified and does not directly apply to other stimuli like double impulses.

In any case, thinking more about it, it seems counter-intuitive to me that low frequencies would be the problematic region for such errors. But we also wandered far from the topic of this thread. So in short: The manufacturer is welcome to provide solid blind A/B or A/B/X results for any audible improvements form this 28 bit DAC - including those in the bass region which you are thinking about :)
 
Nevertheless, bass below 80Hz in stereo recordings “sounds better” to me and other listeners on some recordings played back through some systems and in some formats. More clarity, appropriate decay, etc are clearly discernible as “better”.
Is this really because of the stereo, or it’s more about the dual subwoofer sources—even dual-mono—and their known benefit in averaging the room peaks & dips?
 
And below I think around 80 Hz, it's commonly assumed that we can't locate sound sources as mentioned by @danadam .
That's only true when looking at time-of-flight difference-based localization cues. Level differences are fully effective at all frequencies (as can be easily demonstrated with headphones).
This means low bass can be as directional as anything else depending on the distance of the sound source to the ear. This applies to both real sources as well as rendered image sources. Rendering images that are localized near the head of course poses some difficulties with speakers, but it is not impossible to do.
 
That's only true when looking at time-of-flight difference-based localization cues. Level differences are fully effective at all frequencies (as can be easily demonstrated with headphones).
This means low bass can be as directional as anything else depending on the distance of the sound source to the ear. This applies to both real sources as well as rendered image sources. Rendering images that are localized near the head of course poses some difficulties with speakers, but it is not impossible to do.
But level differences become smaller and smaller with decreasing frequency, because the dampening effect of the head is reduced. So for any "real" sources (as in: not artificially created level differences by using headphones or DSP tricks using speaker arrays and such), this effect should become equally insufficient for localisation.

The linked Wiki article says:
Interaural level differences are very low in this frequency range, especially below about 200 Hz, so a precise evaluation of the input direction is nearly impossible on the basis of level differences alone. As the frequency drops below 80 Hz it becomes difficult or impossible to use either time difference or level difference to determine a sound's lateral source, because the phase difference between the ears becomes too small for a directional evaluation.

Also, the critical point being discussed was time differences because of the idea that those might become problematic with 16 bit data - which I don't think is the case.
 
Interaural level difference at low frequencies where the obstacle (the head) is small compared to the wavelengths is purely a function of the distance difference from the source to the individual ear. Sound pressure in the free field goes with 1/distance and hence if the distances are small then level difference starts to become signficant. I leave it to the reader at what approximate distance from the head we get a 10% (1dB) level difference), may AI help if you want an answer quickly. You'll might surprised.
 
Owners of high-resolution measuring instruments will surely be overjoyed that there is finally an audio device that is better than anything they can measure.
I'm overjoyed that there is finally a solution to a problem I never had and never will have.
This saves me a tremendous amount of money and many sleepless nights.
Sometimes it's actually advantageous to be too stupid to understand every new technological development.
My limited knowledge tells me it's useless for the audio field I use. Please don't correct my subjective, simplistic viewpoint. I can't afford such a correction.
 
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