• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). There are daily reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

CHORD M-Scaler Review (Upsampler)

Rate this product:

  • 1. Poor (headless panther)

    Votes: 333 89.3%
  • 2. Not terrible (postman panther)

    Votes: 11 2.9%
  • 3. Fine (happy panther

    Votes: 7 1.9%
  • 4. Great (golfing panther)

    Votes: 22 5.9%

  • Total voters
    373

Dogcoop

Active Member
Forum Donor
Joined
Feb 12, 2021
Messages
136
Likes
265
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
Misleading???
I think misleading would be, for example, stating that they were able to hear differences in many usb cables but not supplying the proper blind/abx testing to substantiate those claims.
 

tmtomh

Major Contributor
Joined
Aug 14, 2018
Messages
1,619
Likes
4,934
Thanks for the reply, Amir. There is lots to cover here which is why I was hoping to break this down into just one question at a time.

Based on the replies I've seen so far, let me phrase it this way:

I understand and completely agree with running products through tests and you get zero argent from me about any measurements you or anyone else wishes to put products through. Where my concerns arose and the reason I reached out to to Rob was that it appears to me that the M-Scaler is being judged negatively for measurents that are objectively meaningless, specifically:
- the 1kHz tone which you stated did not benefit from upsampling
- the jitter measurement which you stated would be fixed by any decent DAC

Again, I'm not debating the measurements. My concern is there is a lot of discussion here about people being misled by audio companies while I feel that the subjective judgements of measurements that are objectively irrelevant to the real world performance of the device in question (whatever it is) is equally misleading.

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.

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)

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. I also respect the fact that he makes a point of not discussing other people's reviews (regardless of their objective or subjective content). Doing so would create a very combative and potentially disrespectful tone in our hobby. So, Rob not reading the review was in no way disrespect based on what he said to me and he was also quite familiar with much of the content of your review already because it had been posted and discussed at length on Head-Fi.

(I have no need or desire to defend Rob, but will definitely call out unfounded criticism when I see it, no matter the recipient.)

You’re missing a fundamental issue that could make this discussion much simpler: to the extent some of the measurements could be said to be “meaningless,” that’s because they don’t address the M-Scaler’s claim to fix or restore transient losses by upsampling the original signal.

What you’re missing is that @amirm ’s measurements don’t detect that feature because NO measurement can detect that feature. And the reason is that it’s impossible for upsampling to restore anything already lost when a recording was digitized at a lower sample rate.

To put it another way, it is impossible for a transient to be “too fast” for a given sample rate, EXCEPT if the transient is at a higher frequency than the sample rate can encode. And since 44.1k already can capture frequencies up to (and beyond) the limit of human hearing, there is nothing for the M-Scaler to “restore” or “reconstruct,” even if upsampling could do such a thing (which, again, it cannot).

So your argument, and as far as I can tell, that of everyone else critiquing Amir and defending Rob Watts here, boils down to, “I don’t believe that what Amir and others are saying about the basics of digital sampling theory is true - Rob Watts is smart and therefore you guys are untrustworthy, close-minded, and/or incompetent to test or evaluate his gear.”

That’s just bush-league Appeal to Authority fallacy, no matter how much you try to dress it up as some kind of nuanced set of interview questions.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
39,921
Likes
184,775
Location
Seattle Area
That is fine if my tenure is brief. All I am saying is @the_brunx is less than professional. I am also saying that people truly enjoy these products despite measurements. Why does everything have to be proved by blind tests? What is wrong with joy-filled subjectivity? At the end of the day, we are talking about a hobby; it is supposed to be fun, right? I can’t wait to try the M-Scaler. If I try it and dislike it, I will return it just like all of the soulless-sounding-negative-feedback-measurement-seeking Topping products I have tried.
You can have a hell of a lot more fun spending $6000 on family, good food, travel, etc. than spending it on a little metal box that does nothing for your sound. That you want to ignore that and buy it anyway, is of no concern of us. You are not being logical. It is like saying you are going to eat spoiled food and no one should get in your way of doing that by explaining what spoiled food is. Makes no sense.
 

PassionforSound

Member
Reviewer
Joined
Jul 24, 2022
Messages
45
Likes
12
If you have the knowledge then I seriously wonder why this review is your main concern, and why you were not more critical for all the questionable statements Watts made? Upsampling having an effect on timing and depth? Small signals needing at least -301dB accuracy? Unlimited sensitivity for noise floor modulation? No published reseach or blind tests?

Cynically the recent review of the Chord Dave DAC shows it probably has the worst noise floor modulation ever, next to some other deficiencies. Curious how you're going to tackle that.

OK, let's move this conversation forward then. Where is the evidence that the M-Scaler is not improving the accuracy of the timing of transients (or rapid fluctuations of the music waveform - whatever we want to call it) as this is the primary claim from Rob Watts about the benefit of the device.

I agree that the noise floor is higher with the 2x and 4x upsampling modes and I am not going to attempt to debate the subjective and objective merits of triangular and gaussian dither because I am not qualified to. I also think that Chord having these modes active in the M-Scaler is a bit troublesome (as I raised with Rob Watts) and, if I were in charge of Chord, I would probably have had simply 16x or no oversampling and marketed the device entirely for use with Chord DACs.

What I am not seeing is any evidence that the device isn't doing what it claims to do. Before you come back and say that Chord have offered no evidence that it is doing it, that's a different discussion and a reasonable request. My point here is that the M-Scaler is being criticised for not doing anything (or adding extra noise in 2x and 4x modes) when I don't see any measurements actually focussing on what it is claimed to do and other measurements that are objectively irrelevant to its actual performance as confirmed by Amir in his review.

I also don't understand why listening tests weren't conducted at 16x oversampling with the provided Hugo 2 when that is realistically the intended use of the M-Scaler even though it can (but probably shouldn't as I said above) work with other devices.

One final point. I borrowed an M-Scaler ages ago for my review. After spending time listening to it in all modes and using the TT2, I enjoyed its sound (in 16x mode) sufficiently that I purchased it for myself after the review. At the outset of my review process, I had no vested interest in it being good or bad (I have no access to any kind of affiliate programs for any Chord products except sometimes Mojo 2 when it's available via Amazon sellers) but found it to be a very enjoyable addition to the TT2. It's with that experience in mind that I believe it is subjectively improving the listening experience and without evidence to the contrary, I can only assume that it is because of an improvement of the timing information as claimed. There is strong evidence based on studies of auditory processing neurons in the brain that we have very acute timing accuracy in our auditory system so Rob Watts is accurate with his claims about our timing acuity. This IS in my area of expertise. I haven't seen objective data in either direction that proves or disproves this and so I am going with my personal listening experiences at this stage.
 

Dogcoop

Active Member
Forum Donor
Joined
Feb 12, 2021
Messages
136
Likes
265
OK, let's move this conversation forward then. Where is the evidence that the M-Scaler is not improving the accuracy of the timing of transients (or rapid fluctuations of the music waveform - whatever we want to call it) as this is the primary claim from Rob Watts about the benefit of the device.

I agree that the noise floor is higher with the 2x and 4x upsampling modes and I am not going to attempt to debate the subjective and objective merits of triangular and gaussian dither because I am not qualified to. I also think that Chord having these modes active in the M-Scaler is a bit troublesome (as I raised with Rob Watts) and, if I were in charge of Chord, I would probably have had simply 16x or no oversampling and marketed the device entirely for use with Chord DACs.

What I am not seeing is any evidence that the device isn't doing what it claims to do. Before you come back and say that Chord have offered no evidence that it is doing it, that's a different discussion and a reasonable request. My point here is that the M-Scaler is being criticised for not doing anything (or adding extra noise in 2x and 4x modes) when I don't see any measurements actually focussing on what it is claimed to do and other measurements that are objectively irrelevant to its actual performance as confirmed by Amir in his review.

I also don't understand why listening tests weren't conducted at 16x oversampling with the provided Hugo 2 when that is realistically the intended use of the M-Scaler even though it can (but probably shouldn't as I said above) work with other devices.

One final point. I borrowed an M-Scaler ages ago for my review. After spending time listening to it in all modes and using the TT2, I enjoyed its sound (in 16x mode) sufficiently that I purchased it for myself after the review. At the outset of my review process, I had no vested interest in it being good or bad (I have no access to any kind of affiliate programs for any Chord products except sometimes Mojo 2 when it's available via Amazon sellers) but found it to be a very enjoyable addition to the TT2. It's with that experience in mind that I believe it is subjectively improving the listening experience and without evidence to the contrary, I can only assume that it is because of an improvement of the timing information as claimed. There is strong evidence based on studies of auditory processing neurons in the brain that we have very acute timing accuracy in our auditory system so Rob Watts is accurate with his claims about our timing acuity. This IS in my area of expertise. I haven't seen objective data in either direction that proves or disproves this and so I am going with my personal listening experiences at this stage.

This is from your YouTube site:

Passion for Sound
5 days ago (edited)
No Lagunakid, we should believe Rob Watts because he backs up everything he's spoken about here with the scientific (psychoacoustic) and engineering principles that support it


I don’t understand what you are doing here if you already believe “he backs up everything he’s spoken about here (you’re interview with Watts in regards to Amir’s review) with the scientific (psychoacoustic) and engineering principles that support it,” but supplies zero evidence, and don’t understand the various explanations that have been posted here?

BTW a simple null test would confirm your ability to hear differences between properly functioning usb cables. I await the results.
 

dc655321

Major Contributor
Joined
Mar 4, 2018
Messages
1,564
Likes
2,151
Where is the evidence that the M-Scaler is not improving the accuracy of the timing of transients (or rapid fluctuations of the music waveform - whatever we want to call it) as this is the primary claim from Rob Watts about the benefit of the device.

What does “improving the accuracy of the timing of transients” actually mean? Did you put that question to Mr. Watts?

Is this is the “4 microsecond timing needed and 22 microsecond Redbook is not even close” thing from Chord’s marketing material?
 

PassionforSound

Member
Reviewer
Joined
Jul 24, 2022
Messages
45
Likes
12
What you’re missing is that @amirm ’s measurements don’t detect that feature because NO measurement can detect that feature. And the reason is that it’s impossible for upsampling to restore anything already lost when a recording was digitized at a lower sample rate.

Based on my interview with Rob Watts, this can be measured and understood using the digital domain. As I understand it, this involves feeding in the input data and reviewing the output data. My understanding is that you cannot measure it in the analog domain, but that doesn't make it false. Also, not being able to measure something doesn't make it inexistent. The Higgs boson couldn't be found/measured prior to 2012 but was theorised in 1964. Similarly, many of the medicines we are familiar with today (Lithium, Tylenol, Penicillin) are still not understood in terms of how they work. We just know that they do.

Further to that, my superficial understanding of the sinc function theory used as the foundation for the 1,000,000 tap design of the M-Scaler and how it is doing the upsampling (possibly more important than the fact that it is upsampling) is that the fine detail accuracy of the reconstructed wave form gets greater as it moves towards the infinite product. If that is true and the sinc function theory isn't wrong then does it not stand to reason that more processing of that algorithm will result in tighter timing accuracy?
 

iamsms

Member
Joined
Dec 14, 2020
Messages
31
Likes
120
I believe it is subjectively improving the listening experience and without evidence to the contrary, I can only assume that it is because of an improvement of the timing information as claimed.
Why though? That is a very flawed line of thinking. Even if your subjective experience was better with M-Scaler (and lets say it was), why do you have to assume it is because of the improvement of the timing information? Why not start with the assumption that 'we do not know the reason' and then look for reasons/explanations that can/has been proved/disproved. Just because you don't have a reason (or say even the entire scientific/engineering community don't have a reason), why do you have to settle for the reason the engineer is claiming (without proof)? Why not just say 'this is better, and I/we don't know why' and go from there?

Also, I will accept - "There is strong evidence based on studies of auditory processing neurons in the brain that we have very acute timing accuracy in our auditory system so Rob Watts is accurate with his claims about our timing acuity. This IS in my area of expertise. ". I genuinely will. But let me ask you this - how much do you know about signal reconstruction? Do you understand that we hear reconstructed signal, not digital bits? As long as the signal is 'properly' reconstructed, we have the timing information in it.

What is M-Scaler doing to 'more properly reconstruct' the signal in audible bandwidth do you think? Do we have so much aliasing that we can't hear the frequencies near Nyquist limit? What do you think is happening here? I have to know before paying more attention to your questions/reviews.
 

PassionforSound

Member
Reviewer
Joined
Jul 24, 2022
Messages
45
Likes
12
This is from your YouTube site:

Passion for Sound
5 days ago (edited)
No Lagunakid, we should believe Rob Watts because he backs up everything he's spoken about here with the scientific (psychoacoustic) and engineering principles that support it


I don’t understand what you are doing here if you already believe “he backs up everything he’s spoken about here (you’re interview with Watts in regards to Amir’s review) with the scientific (psychoacoustic) and engineering principles that support it,” but supplies zero evidence, and don’t understand the various explanations that have been posted here?

BTW a simple null test would confirm your ability to hear differences between properly functioning usb cables. I await the results.

My point here is that I haven't seen any evidence of the M-Scaler not doing what it is claimed to do. As I said above, inability to measure something doesn't prove its in-existence.

My point in that response in the comments was that Rob Watts offers solid researched (and publicly available) principles to explain why he is making the design decisions he makes. I lieu of actual evidence (not a lack of evidence) that he is wrong, I will trust what I have heard and question the claims coming from this forum that it doesn't do what it is claimed to do. I am very open to being shown otherwise.
 

iamsms

Member
Joined
Dec 14, 2020
Messages
31
Likes
120
Based on my interview with Rob Watts, this can be measured and understood using the digital domain. As I understand it, this involves feeding in the input data and reviewing the output data. My understanding is that you cannot measure it in the analog domain, but that doesn't make it false. Also, not being able to measure something doesn't make it inexistent.

Thank you for saying that, I really appreciate it. There is just nowhere to go from there, at least for me.
 

AdamG247

Fishing Permitted-Must Eat what you catch!!
Moderator
Forum Donor
Joined
Jan 3, 2021
Messages
3,187
Likes
8,514
After spending time listening to it in all modes and using the TT2, I enjoyed its sound (in 16x mode) sufficiently that I purchased it for myself after the review.
The other shoe drops! Finally. Defending the product you own and not disclosing that fact up front is dishonest and misleading. All the virtue signaling in the beginning was suspicious and now we know why. :facepalm:
 

PassionforSound

Member
Reviewer
Joined
Jul 24, 2022
Messages
45
Likes
12
Why though? That is a very flawed line of thinking. Even if your subjective experience was better with M-Scaler (and lets say it was), why do you have to assume it is because of the improvement of the timing information? Why not start with the assumption that 'we do not know the reason' and then look for reasons/explanations that can/has been proved/disproved. Just because you don't have a reason (or say even the entire scientific/engineering community don't have a reason), why do you have to settle for the reason the engineer is claiming (without proof)? Why not just say 'this is better, and I/we don't know why' and go from there?

Also, I will accept - "There is strong evidence based on studies of auditory processing neurons in the brain that we have very acute timing accuracy in our auditory system so Rob Watts is accurate with his claims about our timing acuity. This IS in my area of expertise. ". I genuinely will. But let me ask you this - how much do you know about signal reconstruction? Do you understand that we hear reconstructed signal, not digital bits? As long as the signal is 'properly' reconstructed, we have the timing information in it.

What is M-Scaler doing to 'more properly reconstruct' the signal in audible bandwidth do you think? Do we have so much aliasing that we can't hear the frequencies near Nyquist limit? What do you think is happening here? I have to know before paying more attention to your questions/reviews.

Thanks for approaching this question respectfully!
I am accepting the explanation of timing accuracy because the pieces of the puzzle (the theories and principles proposed by Rob Watts as the explanation) make sense. It doesn't mean I won't consider alternate opinions or evidence, just that I am operating on that assumption until evidence to the contrary comes forward.

I don't know much about signal reconstruction and again defer to the fact that the theories proposed make sense and I haven't seen evidence to the contrary. If someone can show me evidence that the WTA approach is no different in its reconstruction (at a timing accuracy level because that's its claimed difference) when compared to regular filters in other delta sigma DACs I will gladly change my mind.

As for more properly reconstructing the signal, see above and post #1127 about the sinc function
 

PassionforSound

Member
Reviewer
Joined
Jul 24, 2022
Messages
45
Likes
12
The other shoe drops! Finally. Defending the product you own and not disclosing that fact up front is dishonest and misleading. All the virtue signaling in the beginning was suspicious and now we know why. :facepalm:

There was no deliberate intent to hide it and I have no need to defend my purchase choices in a subjective hobby where everyone is entitled to enjoy whatever they like
 

DonR

Major Contributor
Joined
Jan 25, 2022
Messages
1,760
Likes
3,082
Location
Vancouver(ish)
Thanks for approaching this question respectfully!
I am accepting the explanation of timing accuracy because the pieces of the puzzle (the theories and principles proposed by Rob Watts as the explanation) make sense. It doesn't mean I won't consider alternate opinions or evidence, just that I am operating on that assumption until evidence to the contrary comes forward.

I don't know much about signal reconstruction and again defer to the fact that the theories proposed make sense and I haven't seen evidence to the contrary. If someone can show me evidence that the WTA approach is no different in its reconstruction (at a timing accuracy level because that's its claimed difference) when compared to regular filters in other delta sigma DACs I will gladly change my mind.

As for more properly reconstructing the signal, see above and post #1127 about the sinc function
hypotheses, not theories. It is unproven speculation.
 

dc655321

Major Contributor
Joined
Mar 4, 2018
Messages
1,564
Likes
2,151
I don't know much about signal reconstruction and again defer to the fact that the theories proposed make sense and I haven't seen evidence to the contrary. If someone can show me evidence that the WTA approach is no different in its reconstruction (at a timing accuracy level because that's its claimed difference) when compared to regular filters in other delta sigma DACs I will gladly change my mind.

Here ya go, courtesy of @mansr - https://www.audiosciencereview.com/forum/index.php?threads/chord-quest-vs-rme-adi-2-dac-fs-tap-count.22124/post-734918

EDIT: also from Mans, because this seems to be what you're misunderstanding (or have not understood).
 

PassionforSound

Member
Reviewer
Joined
Jul 24, 2022
Messages
45
Likes
12
hypotheses, not theories. It is unproven speculation.

Yes, but show me the evidence that you are using to say that it doesn't do anything? It seems that both sides are speculating at this point and it's pointless. If no-one has any actual evidence that it's claimed objective benefits are/are not real then everyone should just go back to enjoying the music and agree that some things can't be measured.
 

DonR

Major Contributor
Joined
Jan 25, 2022
Messages
1,760
Likes
3,082
Location
Vancouver(ish)
Yes, but show me the evidence that you are using to say that it doesn't do anything? It seems that both sides are speculating at this point and it's pointless. If no-one has any actual evidence that it's claimed objective benefits are/are not real then everyone should just go back to enjoying the music and agree that some things can't be measured.
Burden of proof lies at the feet of the claimant. Russell's teapot.
 

PassionforSound

Member
Reviewer
Joined
Jul 24, 2022
Messages
45
Likes
12
I don't know much about signal reconstruction and again defer to the fact that the theories proposed make sense and I haven't seen evidence to the contrary. If someone can show me evidence that the WTA approach is no different in its reconstruction (at a timing accuracy level because that's its claimed difference) when compared to regular filters in other delta sigma DACs I will gladly change my mind.

Thank you, but without any information about timing accuracy, this doesn't help
 

PassionforSound

Member
Reviewer
Joined
Jul 24, 2022
Messages
45
Likes
12
Burden of proof lies at the feet of the claimant. Russell's teapot.

I agree. Where is the proof that the M-Scaler doesn't do what it is claimed to in relation to timing accuracy? That is the claim of Amir's review and many on this forum. If you want proof from Chord, that's fair and reasonable too.
 

iamsms

Member
Joined
Dec 14, 2020
Messages
31
Likes
120
Top Bottom