• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many 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: 358 88.2%
  • 2. Not terrible (postman panther)

    Votes: 13 3.2%
  • 3. Fine (happy panther

    Votes: 7 1.7%
  • 4. Great (golfing panther)

    Votes: 28 6.9%

  • Total voters
    406

BeerBear

Active Member
Joined
Mar 9, 2020
Messages
264
Likes
252
I included audio samples. Can you tell the difference between them?
After a quick try... nope, I can't.
But I also can't entirely eliminate the possibility that it might be possible for some people in some cases (speaking of upsampling in general, involving all kinds of audio gear and poor filters...).

I expected this forum to help saving time when choosing gear, not the other way around :eek:;) Besides, I don't rate my own assessment capabilities on this field very high so I prefer an objective measurement and read informed people's opinions.
I would not recommend buying any gear without some solid evidence of audible benefits and so far I haven't really seen any for upsampling. The differences we're talking about here occur, for the most part, at very high frequencies, which are usually considered inaudible.
That's why I think you're not missing much if you just ignore this stuff. But objective measurements can only tell you what's there, not what you hear or don't hear. So if you're really curious, you can do similar experiments using software, for free.
 

AudioSceptic

Major Contributor
Joined
Jul 31, 2019
Messages
2,691
Likes
2,534
Location
Northampton, UK
This is a review, listening tests and measurements of the CHORD Hugo M-scaler upsampling digital transport. It is on kind loan from a member and costs US $5,295 (some show it as $5,650).

View attachment 216660

We have the usual lightshow of buttons as other CHORD digital products but here, due to less overloading of the buttons, it is not hard to navigate. Still, it is annoying to have to keep looking up the color coding in the manual until you memorize them. Here is the back panel:
View attachment 216661

The unit accepts digital audio over either USB or S/PDIF inputs (coax and optical). Very oddly for a device in this class, a large PC laptop type power supply is provided, needlessly causing anxiety for most of their customers buying this tweak. An internal power supply should have been provided. Output is in the form of S/PDIF again or dual BNC outputs which is proprietary to CHORD. Fortunately the member kindly provided a Hugo 2 and all the necessary (high-end Nordost) cabling to make the system work.

If you are unfamiliar with the marketing of this product, it takes an input and upsamples it to higher rate using incredibly high number of taps. High taps allows sharper transition from pass-band to ultrasonic. Company claims that one needs huge number of taps for better fidelity, literally going to millions of them. This has a side-effect of creating fair amount of latency so there is a "video" mode where if it detects 48 kHz sampling, it will shut off the upsampling (or lowers its taps?). While 48 kHz is a common sampling rate for video, many other rates are used so this is not a full fix. Fortunately a "bypass" mode is also provided which basically disables the filter. However, it still lowers the levels to make it match the level when upsampling is used (needed for headroom as to avoid overflow). Company rightly realizes that if the volume is higher in bypass mode, customer may think that sounds better and reject the whole notion of the unit. If so, I wonder then why company doesn't believe in going the next step and providing level matched, controlled blind test to show the efficacy of the unit.

Back to upsampling, the rates provided are 2X, 4X and 16X with the latter needing dual BNC connection at 768 kHz.

CHORD M-Scaler Measurements
My first test was to examine the quality of the Coax output with respect to jitter. Results were disappointing and depended in how you output bits to the unit. Let's start with USB connection:

View attachment 216665

The green line is the Audio Precision analyzer measuring jitter spectrum of its own Coax signal. The red, green and orange lines are what we get when we send the same digital signal through M-Scaler, i.e. USB In/Coax out to the analyzer. We see a large increase (in relative terms) of the baseline noise indicating random jitter. The correlated spikes are elevated much higher as well.

Turns out the above was the "good case." Here is the bad case when we use Audio Precision's coax output to feed the M-scaler:

View attachment 216667

Good grief. What is going on here? Not only do we have the same baseline (higher) noise floor but now have distinct deterministic spikes coming out of the unit. I captured the AP and M-Scaler's computed jitter level and it is embarrassingly bad:
View attachment 216668

It is so bad that you can see the problem just looking at the waveform of jitter:

View attachment 216669

On the left we see AP analyzer's benign, very low level noise. On the right we see clearly, somewhat sinusoidal of M-scaler. I have tested $100 digital bridges that far outperform the M-Scalar on this front! As a way of reference, 500 picosecond/0.5 nanosecond is enough jitter to equal one bit of 16 bit digital audio sample. M-Scalar is outputting 8X that amount!

Fortunately any half-respecting DAC will filter this and not let it in the output but still, what is the claim to fame of M-scaler if it is not precision of its digital transformation? Let's save our frustration for other test results.

Next I connected a Topping D70S to the analyzer and captured its output by itself:
View attachment 216670

We see the great performance that we expect from this DAC. Now let's put the M-scaler in the loop:

View attachment 216671

What the heck happened here? Even in pass through mode performance of D70s is heavily degraded. We have spikes at oddball frequencies which I can't explain. I see reviewers with company blessing using M-scaler with third-party DACs. I would say be cautious, very cautious doing so.

Fortunately there was no problem using M-scaler with Hugo 2:
View attachment 216672

Then again there was no benefit to upscaling either:
View attachment 216673

And here is the response with dual Coax:
View attachment 216676

Still the same.

I should note that the Hugo 2 was running on battery for all of these tests per suggestion from the owner.

Let's go back to basics and see if the M-scaler is doing what it is supposed to be doing by running our filter test with the D70s:
View attachment 216674

It is indeed. Both 2X and 4X modes provide an ultra sharp response. However they do so at the cost of higher noise floor/lower attenuation.

I ran a very high resolution frequency response test focusing on the end of the spectrum and results are basically the same in all modes:
View attachment 216675

The bypass mode has the sharp filter and the others do not because the DAC is operating at higher sample rate. With respect to audible band up to nearly 22 kHz though, the frequency response is essentially the same. So anyone saying tonality has changed with upscaling modes needs to re-think that.

CHORD M-scaler and Hugo 2 Listening Tests
Conveniently, the switch between bypass and 2X upsampling was seamless. So I used that to perform listening tests. I say some because the button cycles to higher rates and there, it causes a glitch/pause which completely throws off your mind. Going by forward mode of bypass to 2X, I detected no difference at all. Nothing changes as far as tonality, soundstage, etc. I captured a couple of samples for you to listen as well:



You can listen right in the dropbox or download them. If you are sure there is a difference, go ahead and say which one is M-scaler bypass and which is 2X.

FYI I could not run a null test with DeltaWave as there is too much clock drift and clips are not lined up. The difference shown was the same as two consecutive captures without changing anything.

Conclusions
I was very disappointed to see high noise levels and jitter on Coax outputs of such an expensive digital products. And one where its designer claims you can hear problems at 300 dBFS. Well, if you can hear that well, then maybe you can hear this jitter too so I suggest not releasing a product that performs this bad. Second, there is a serious compatibility issue with third-part DAC that I tested. Maybe it is OK with other DACs, I don't know. But grabbing a sample DAC and having such serious degradation in its performance with M-scaler is very concerning.

Putting design issues aside, I found no audible difference in upsampling with company's own DAC. As it should be. The differences in the filter are above audible band so they should not be audible. Is it nice to have a sharper filter? Sure. But I sure as heck wouldn't pay nearly $6,000 to get that.

Bottom line, I don't see a reason to own M-Scaler. It can damage the audio signal in some cases and in others, provide no audible benefit. If people think otherwise, I highly suggest performing a blind test with enough repetition to provide statistically valid results. Otherwise, the M-scaler remains as a product with no purpose.

Needless to say, I can't recommend the CHORD M-Scaler.

-----------
As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
I never could understand the point of the M-Scaler when a competent DAC already does all that you need, but I had no idea that it would actually make things worse! At best I thought that you would be wasting money on perfect performance but inaudible improvements, but you are not even getting that. I wonder what any user thinks they can hear to justify the very high price. Is this the worst digital product that Chord makes?
 

PeteL

Major Contributor
Joined
Jun 1, 2020
Messages
3,303
Likes
3,838
To it's specs thought.
(please excuse me if bits can reduce a dac's sinad.etc.,I don't know that much)

When I say immune I mean in terms of noise,jitter,etc.
For example I don't remember the exact case but I remember that a single isolator between the circuit and the screen circuit of an expensive dac save it in it's current version (and it was the only thing added.)
There is a couple different things. If a Dac is USB powered and the Power is noisy, but Data is clean, that's one thing, but if signal line is so noisy or fluctuating that it don't ressemble a squarewave anymore, some bit flips will occur, something that was suppose to be low level (0) may show up high level (1) because of the noise on the line. That's noise. There's a limit to what jitter can be corrected too but that limit is quite high, it shouldn't matter in most modern dacs. . In both case, we have an error rate. Errors are random. By definition bit errors that have a random nature will be converted as noise, bit errors that are correlated to the signal will be converted as distortion. Both influence SINAD yes. But we don't even have evidence that it's what happening. The signal itself may have error in it from the source, in the sense that it would have been modified and not bit perfect, but that will be a Sinad hit anyway. errors are errors.
 
Last edited:

spooky

Active Member
Joined
Jan 30, 2021
Messages
136
Likes
36
Did you not consider testing the higher sampling rates? The review seems incomplete and ideally would have been done with a TT2.
 

fordiebianco

Senior Member
Forum Donor
Joined
Mar 11, 2020
Messages
355
Likes
752
Location
British Isles
  • Like
Reactions: MJB

Sokel

Master Contributor
Joined
Sep 8, 2021
Messages
5,834
Likes
5,760
By definition bit errors that have a random nature will be converted as noise, bit errors that are correlated to the signal will be converted as distortion. Both influence SINAD yes.
I really didn't know that,all this time I thought that "bad" bits would be rejected or something.
Thanks for that!
 

PeteL

Major Contributor
Joined
Jun 1, 2020
Messages
3,303
Likes
3,838
I really didn't know that,all this time I thought that "bad" bits would be rejected or something.
Thanks for that!
There is no error correction neither in SPDIF or USB audio. There is error corrections in the IP protocols (like in audio over IP), or in file transfers (like in ripping a cd). but not in what a regular DAC can do.
 

Jomungur

Member
Joined
Jan 3, 2022
Messages
92
Likes
591
High end audio is about selling dreams. Lot's of people who want to believe.
These type of comments are really interesting. My experience is it's not quite like this.

Let's say you are in a position where you have enough disposable income so that for you personally, time is more important than the money needed to buy a high end audio system. Let's say that you like audio but don't have the time or knowledge to put lots of pieces together and test components in isolation. It's also impossible to tell from reviews because they are all over the place. Let's say you can hire someone who designs complete audio systems, the kind of person who will go to your house/apartment, do an acoustical test and configure everything. You give them a budget of $100-$150k to get a system for you. Person has been recommended to you from a friend.

You go to his/her studio and listen to various speakers and set ups. Different speakers do sound different. There's no pressure, actually, you can come back and listen several times on different days to be sure.

You are not being an idiot. You don't have time to really care about each individual component, and you know you are probably buying unnecessary things. That's understood. You also know that some of the cost is made up because the consultant gets discounts and you don't pay list price on anything (easy to check). It happens to be the M Scaler is part of the set up, but is about 3-5% of the total cost of the set up. You don't have time or really care about each individual component. Since you know you like how it sounds as a whole you go for it. System set-up and you are happy.

Is it a waste of money? Sure, on some level. If I did it again I would leave out the M Scaler as part of the package. But it's not irrational. Just depends on your personal valuing of time vs. money. It's a lot of work to test audio components, assuming you have the know-how. One of the reasons the M Scaler stayed in my system despite my doubts is it didn't seem to hurt, and I'd rather listen to my system than swap cables which are admittedly in an inconvenient spot for me (out of sight).

I only found this website this year. And as I get into the technical aspects audio more and more, I am curious about what each of these parts do, if anything. And I've frankly been a little shocked at the lack of transparency of the industry, and in particular the audio reviewing industry. I have to think that if a company provides you with a review model, it will bias you a bit because you want the next one, right? You need products to review, or your website will never take off. So if you have a positive evaluation of a company loaned product you will post it, but if you have a negative evaluation, you have every incentive to simply not post the review rather than give a negative review. Hence my support of what Amir is trying to do.
 
Last edited:

Sokel

Master Contributor
Joined
Sep 8, 2021
Messages
5,834
Likes
5,760
There is no error correction neither in SPDIF or USB audio.
That would be a step forward if possible.
(then again if it was someone would already have done it so we stay in what we have)
 

PeteL

Major Contributor
Joined
Jun 1, 2020
Messages
3,303
Likes
3,838
That would be a step forward if possible.
(then again if it was someone would already have done it so we stay in what we have)
That's one of a reason Network based audio is gaining momentum i think, it allows that. Sure there would be ways to get that with USB as well but it's not. The USB Audio Class 2 protocol has ressources to detect errors, for developpers error rates can be monitored but not corrected, a sample with error in it will be converted with them.
 

Jimbob54

Grand Contributor
Forum Donor
Joined
Oct 25, 2019
Messages
11,064
Likes
14,694
Goldensound performed similar tests and to my untrained eyes, the takeaways are about the same:

Bad jitter -especially on SPDIF inputs - Chord DACS seem to be able to handle it- 3rd party products not so much.

Nice steep filters - but GS measurements seem to suggest it drops over 100dB quickly whereas Amir measured more like 80db- maybe I am misunderstanding this bit. Interestingly, when he measured the DAVE with and without the Mscaler in play- the filters look about the same to me

 

Jimbob54

Grand Contributor
Forum Donor
Joined
Oct 25, 2019
Messages
11,064
Likes
14,694
Did you not consider testing the higher sampling rates? The review seems incomplete and ideally would have been done with a TT2.

What would change if either of these had been done, do you think?

 

AudioSceptic

Major Contributor
Joined
Jul 31, 2019
Messages
2,691
Likes
2,534
Location
Northampton, UK
Hey guys, I'm going to out myself on this one. I loaned these. I had my suspicions about the M Scaler; I use Chord DACs (main DAC is not the Hugo2) and it was hard to tell what it was doing to the sound, if anything. Still, it's disappointing that such an expensive product has such poor results. I'm not a technical person, but I think Amir is saying that the M Scaler does what it says it does but that the "improvement" is not discernible on an audible level?

Anecdotally, I've been listening to my audio system without the M Scaler the past week and I can't tell the difference. Anyway, hope ASR's review helps someone who was considering purchasing this item. There are some extremely glowing reviews of the M Scaler out there.
Unless I misread Amir's review, it actually, measurably, makes things worse, so at best it's audibly doing f*** all.
 

Jomungur

Member
Joined
Jan 3, 2022
Messages
92
Likes
591
Any chance your unit is defective?
It's possible (I haven't compared it to other models), but I don't think so. With both the Hugo2 and the DAVE, the DAC tells you the sampling rate of the input signal. The Hugo2 tells you by color and the DAVE gives you a numerical readout. And sure enough, when I hit 16x on OPX button on the M Scaler, the receiving DAC immediately recognizes the increased sample rate (768hz in that case).
 
Last edited:

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
7,604
Likes
7,313
Location
UK
Did you not consider testing the higher sampling rates? The review seems incomplete and ideally would have been done with a TT2.
Do you disagree with the measurements? Do they not show that the insertion of the device in the audio chain does nothing beneficial that can be measured?
 

testp

Senior Member
Joined
Jul 22, 2020
Messages
390
Likes
229
Please elaborate. First time I heard this term.
ok, i should have phrased it a little better, its like certain ppl who shop to feel better, buying accessories that might not provide anything else, so based on the measurements i consider this product being that..
 

spooky

Active Member
Joined
Jan 30, 2021
Messages
136
Likes
36
What would change if either of these had been done, do you think?

Well perhaps a different level of upscaling might have produced a noticeable difference. Otherwise it's like testing a mountain bike by riding it to the pub (assuming you don't live up a mountain). Or maybe doing the shopping in a supercar and not taking it to a track. You're only getting part of the picture. The review is surely incomplete if only the lowest of the upscaling options is used.

Subjectively, I found a difference with the higher upscaling levels with a TT2 (particularly the middle setting). With a DAVE I'm not convinced it makes as much, if any, difference to my ears with my speakers in my room. I might actually prefer my DAVE without the M-Scaler - perhaps that's related to noise or just my personal preference.
 

sarumbear

Master Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
7,604
Likes
7,313
Location
UK
Any chance your unit is defective?
The faulty unit excuse has arrived. This time it took 72 posts.

However, given the fact that the device is not doing bad things to the signal the fault description is now pretty unique: It can’t improve the quality of the audio because it’s broken but it doesn’t hurt the signal.
 

BeerBear

Active Member
Joined
Mar 9, 2020
Messages
264
Likes
252
Archimago published an article regarding the use of bazillion number taps upsampling: Archimago's Musings: Mega-taps upsampling: Remastero's Pan Galactic Gargle Blaster (PGGB) software. (Broadly on audiophile software & the noise boogeyman.)

In the article he uses 'Remastero', a software to apply the filter offline because it takes so much CPU and time to calculate that applying it in real time isn't feasible. It goes further than what the Chord is attempting.

Guess what the outcome is .... "Alas, I see/hear no evidence of any "magic" here and whatever special processing is being done seems to be low-level and inaudible".

Also a DeltaWave analysis didn't show any meaningful.
Seems reasonable. But bazillion taps is not important, IMO. The difference, if any, should happen with even simple upsampling for a DAC that has really poor filtering and with speakers/headphones that are very sensitive to ultrasonics and with IMD lower in the spectrum... All of this coupled with the right audio material and with good hearing abilities could result in something audible.
Hypothetical far fetched situations, sure, but that's at least theoretically where I see upsampling being potentially beneficial.
 
Top Bottom