I do not think this is true. Adding to @dc655321's post IMHO it is totally clear what the idea is: provide the best possible approximation to the ideal, the true sinc() reconstruction via upsampling, basically replacing the downstream DAC's filter. In a hardware blackbox, besides the cheaper but less convenient option of doing this software.Ultimately, the problem is what has been said many times in this thread: the M Scaler is impossible to really test in terms of measurements because it's impossible to quantify what is it is supposed to do. Even the transients point doesn't seem to hold up in measurements.
What constitutes best, though? Is it stopband attenuation? Passband flatness? Transition sharpness? Since we can't maximise all of those at the same time, what compromises are acceptable? Rob Watts takes a very simplistic "more taps better" view, and like the sheep in Animal Farm, his acolytes are happily bleating this mantra. It is, however, anything but clear that his approach has any merits compared to traditional methods.IMHO it is totally clear what the idea is: provide the best possible approximation to the ideal, the true sinc() reconstruction via upsampling
The two measurements I've flagged don't prove that and yet it's already being judged.
I see, thanks. Well, I'm not a sound engineer so I am probably way ahead of my skis in trying to understand this. I can tell you this, though, most dealers have no idea what it does.I do not think this is true. Adding to @dc655321's post IMHO it is totally clear what the idea is: provide the best possible approximation to the ideal, the true sinc() reconstruction via upsampling, basically replacing the downstream DAC's filter. In a hardware blackbox, besides the cheaper but less convenient option of doing this software.
True sinc() reconstruction takes the DAC fully out of the picture (except effect of its analog post-filter), what comes out are the sample values the recording ADC generated, plus exact waveform in between the samples. Therefore, the only filter function in place is that of the ADC, a combination of the analog pre-filter and the internal filter used for downsampling to the target output rate.
[Sidenote: Again, this process can be offloaded to an extra step by running the ADC oversampled and then apply a perfect sinc() filter (in software) for downsampling]
Obviously, this point becomes moot if the music is highly processed and/or non-acoustic source. However, for well-recorded acoustic music and the like, this device fulfills the whole idea of high fidelity, do not harm the original signal.
One practical drawback of true sinc() filtering/resampling is that you you need the highest amount of headroom for intersample-overs which is why the digital output level of the device is lowered.
As for audibility of all this, after a few tests I did in software (with a special version of the SoX tool) I'd say no, sorry.
no, no, no. Please don't mind if I correct some errors contained in your post. you should have written a correct summary of the evidence: "It is possible to test the M-scaler in terms of measurements. Some of these tests have shown objective defects, such as increased jitter on digital outputs and induced distortion in a non-Chord DAC connected to the M-scaler. Other standard measurements of digital devices performed on the M-scaler showed no benefit to upscaling." I find this phrasing more correct as a thread digest, thank me later.the M Scaler is impossible to really test in terms of measurements because it's impossible to quantify what is it is supposed to do. Even the transients point doesn't seem to hold up in measurements.
This product has been marketed as perfecting the perfection of their DACs. Now we hear that it doesn't have a great PLL and spits out jitter?- the jitter measurement which you stated would be fixed by any decent DAC
We only know this after I tested it. Prior to that, you wouldn't know if noise floor is way elevated for example. Or modulated as I discovered in the DAVE DAC yesterday. It could have also overloaded and clipped with 0 dBFS signal. And again, remember that the DAC is now running at higher sample rate and so that would change performance as well.- the 1kHz tone which you stated did not benefit from upsampling
Instantly? Why wouldn't they read the full review? BTW, they should be turned away because the entire measurement set shows that the M-scaler can actually degrade performance. And at best, it doesn't do anything other than provide a sharper reconstruction filter.Let's pretend for a moment that the M-Scaler does do what it's said to. If someone new to the hobby we're looking around for reviews and saw your comments on the 1kHz tone test (with Hugo 2) and on the jitter test, they'd likely be instantly turned away because they wouldn't necessarily understand that neither measurement matters.
My opinion has nothing to do with it. Or I would not bother testing any of these tweaks.So, I guess my question here is this. Are you looking to provide objective data and unbiased interpretation of that data or are you using the data to illustrate your own opinions of the products? (I am not judging either approach and not suggesting any manipulation of the data)
I don't see the distinction whatsoever. You asked him questions about my review and measurements and even showed the snapshots. This was the entire scope of the long interview. You also set it up as reading my review and thinking the product doesn't perform. I can't believe you are walking back from this.Finally, I want to clarify here that I reached out to Rob Watts to ask him to answer my questions about the measurements, not to read and critique your review.
This is the part I don't understand - RW claims this on head-fi and maybe other places, then goes on to do an interview (or maybe before), and nobody questions him "what is your source for this claim". Not even the interviewer who is supposed to play the role of a journalist here.That they used a noisier gaussian dither. Rob claims this is good for sound but he doesn't have a shred of evidence to provide. And literature shows that he is mistaken in this.
Please stop assuming you understand my motivations or have any real sense of my competency or knowledge.
I already explained you the scope of this judgement, being noise and distortion performance. And as explained, all parameters being measured are judged. Also when they're only relevant from a technical perspective. Hence the evaluation of jitter performance. So why insist?
Obviously the replies you've gotten don't fit your chosen narrative. They're not going to change. Either accept technical reality, or be elsewhere I think.I ask this because the content is put forward, as I understand it, as objective and unbiased. The conclusions don't seem to support this and I find that to be misleading so I am seeking clarification as to the intention - nothing more