The Chord Electronics Hugo M Scaler is a unique high-end upsampling component capable of upsampling digital streams from 44.1k up to 705.6kHZ (maximum of 768kHz). It is priced at £3495.

Disclaimer: The Chord Electronics Hugo M Scaler sent to us is a sample in exchange for our honest opinion. We thank the team at Chord Electronics for giving us this opportunity.

You can read more about Chord Electronics products we reviewed on Headfonics by clicking here.

Chord Electronics Hugo M Scaler
The concept of a 'lens' on your music is apt, the idea that dynamic range and how 'vivid' your best setup can sound can be improved is relevant. However, you need a revealing setup to get the benefits.
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The Right Setup

The gestation period for this M Scaler review has been long, perhaps almost too long. However, the upshot is a degree of familiarity with the capability of this device almost like no other before putting pen to paper.

That is a critical point because if you simply plug the M Scaler into a DAC, turn on your amp and connect some headphones you may not necessarily get what the big deal is at first. That initial listen might not reveal what the magic is. That, combined with the top-tier pricing, might leave you feeling underwhelmed.

I had that initial issue during CanJam Singapore 2019 with a set of HE5SE’s from Hifiman plugged into a TT2 with the M Scaler right behind it. The HE5SE is not a reference headphone and its old school technical capability leaves much to be desired in terms of imaging. Its timbral qualities are appealing, technical capability less so.

Picking the right setup, the right headphone and tracks you know and understand is critical to overcoming that first hurdle. The Hugo M Scaler is not a quick fix timbral choice. It is not an EQ tool nor will it redefine the core FR of any headphone. The secret sauce of the M Scaler lies in the technical domain and in that domain it can and is utterly brilliant.


Chord M Scaler

Tech Inside


In short, The Hugo M Scaler is a standalone upscaling device that acts as the first port of call for any digital audio source or transport such as a laptop or CD Player. It then sends the resulting upsampled digital signal to the DAC of your choice for decoding into analog.

The upsampling technology first saw the light of day on their flagship BLU MKII digital/CD transport launch a year or two ago so it is not an entirely new line of technology from Chord. However, it is officially Rob Watt’s most advanced version at the time of writing and their first such standalone device to focus solely on upsampling.


The M Scaler uses a complex Xilinx XC7A200T FPGA with 740 DSP cores to create WTA (Watts Transient Alignment) filtering capable of upsampling digital streams from 44.1k up to 705.6kHZ (maximum of 768kHz).

DACs such as the Hugo 2 and Qutest actually share the same initial stage of converting a digital signal as the M Scaler, (upsampling). Duplication? Not quite because by using the M Scaler to bypass the initial stage or WTA 1 this is seen as a considerable upgrade on their stock stage 1 DAC process.

That is quite important as virtually all DAC’s have some element of upsampling but perhaps not as complex as the M Scaler. Therefore, regular DAC upsampling interpolation or resulting resolution may not be as accurate compared to the M Scaler output. That upscaled signal is then finally sent to the connected DAC which recognizes it in its new upsampled state rather than the original source rate.

Modular Benefits

By ‘outsourcing’ the process to a dedicated component, not only are Chord able to dedicate all the power required by the M Scaler’s internal FPGA but they, in turn, can build a modular system that is properly equipped at reducing any noise from those additional power demands.

The M Scaler is also not restricted to any single source such as a CD player. It can be attached to any compatible transport and DAC. It has the functionality to pair with any USB-capable output such as a laptop but ideally, it works best with a Chord Electronics DAC for a few reasons.

Chord DACs

Pairing with Chord DACs is not just sales speak in favor of Chord products. Whilst you can link the M Scaler to any DAC, the inclusion of dual BNC connectors means you can directly link 2 BNC cables to the likes of the DAVE, TT2, and the Qutest (which we have here) and all will recognize the M Scaler and respond accordingly.

A dual BNC connection will also give you the highest rate of sampling possible at PCM 768kHz (from 96kHz input). Other single BNC DACs will tap-out at PCM 352.8 kHz.

Of course, you are not limited to BNC input and outputs with the M Scaler. You can also use an optical and coaxial output as well as 2 optical inputs giving you the potential to link up to 4-5 different sources to the M Scaler and upsample and output to 3-4 different DACs.

Chord M Scaler


The M Scaler is unmistakably a Chord Electronics product. There is a certain ethos, design flow if you will, for any Chord Electronics gear from the Mojo up to the DAVE and the M Scaler is no different.

Well, it has to be that way to fit neatly on top of a TToby or TT2 which is how the team has envisaged this all comes together. For those that are coming from a Hugo or Hugo 2, it is a bit like having a giant version of that design, the two are not that far off.

It is also extremely robust with a very high level of build quality. The silver-finished chassis, much like the Hugo 2 is carved from an aluminum block and consists of two parts adorned with 4 rubber feet on the base and held together with 4 discreet screws.


The front houses the same color orb scheme as the Hugo 2 also, although on a more complex level. From left to right there are options for Video filtering, input selection, sample rate as well as 3 DX choices which only come alive when they receive a sample rate (DX OP) or, as Chord Electronics has alluded to when connected to future product lines that have yet to be revealed.

Input Selection

The Hugo M Scalers input selection on the left is color-coded with up to 7 color options. Two of these options are more of an auto-select and the rest a manual selection. Those two are coded pink for automatic and blue for automatic Dual BNS.

Basically, if you set the M Scaler to the pink it will default to whatever source is currently connected and active without you having to worry about chopping and changing. Pink will be the default input selection for the majority of systems. The remaining manual sections are as follows:

  • White – USB
  • Orange – BNC 1 input
  • Red – BNC 2 input
  • Green – Optical 1
  • Dark Blue – Optical 2

Chord M Scaler

Sampling Rates

The switchable sample rate or OP SR is your key button on the M Scaler for audio playback. Here you can select from 4 core options and they are also color-coded:

  • Red – low
  • Green – medium
  • Blue – high
  • White – maximum

The designations are a little crude but it is more a high-level interpretation of what to expect. The actual sample rates you will get under each designation do vary with factors such as the input medium, (USB, BNC or optical) and the output cable (BNC, dual-BNC, and optical).

For reference purposes, only Dual-BNC output will give you the top rate of 768kHz output. Optical output has a maximum upsampling capability of 176.4kHz which is logical considering you cannot go further than 24/192 on an optical interface. If you are using hi-res files already, (24/192), the benefit of using optical output upsampling is marginal to none.

If you elect to use a single BNC input or single BNC output to a 3rd party DAC then the maximum sampling rate is capped at 352.8kHz input and 384kHz output. Even if your input is USB and your output is a single BNC then the output rate is the same. This is the benefit of going Dual-BNC with Chord own DACs which can receive a Dual-BNC cable input.

Video Filtering

Just a note on the far-left video filtering feature which is slightly different from the core switchable sample option. You will not get quite the optimal tap length and sample rate output using video because of the latency inherent in the upsampling process.

The video feature thus lowers the sampling marginally to achieve a proper sync with audio and video from your source file. Having tried that using YouTube and some high bit rate local storage video files I can confirm it does exactly that.

Chord M Scaler


One other function, and one that Chord Electronics product users often find necessary is the ability to dim those orb lights. You can dim or enhance the orb light strength via the last two DX buttons. Generally speaking, I tend to take them all the way down so they do not distract me when watching a movie or streaming.

The Orb light sequence works in much the same manner as the Hugo or Qutest and with dual BNC I have found our Qutest to match the color sequences of the M Scaler, particularly for sample rates which are very assuring.

Chord M Scaler


The rear panel is more of a traditional hi-fi design rather than the inset Hugo 2 style which I do like. Mind you it is not really possible to inset BNC connections and there are 5 coaxial sockets for that, with 4 dedicated for BNC (input and output) and one for SPDIF (output).

The Hugo M Scaler does use a switching 15V/4A SMPS power supply but I am told the power demands are not that high for a desktop product.

In the middle, you have 3 optical ports, 2 for input and 1 for output and a single USB socket for receiving a digital signal from the likes of your PC or other digital audio transport.

This is my first time working with BNC cables but I am impressed with their locking mechanism. Just a simple push, twist and release and it grips tight. the cables also seem pretty sturdy though not terribly long so you do need your partnering DAC fairly close.

Chord M Scaler


The Hugo M Scaler is designed to be the first stop digital processor from whatever transport you are using and before the source signal is decoded to analog by a DAC.

So long as you have an outgoing connection either via USB, coaxial or optical then the setup is entirely up to you and the system you have. Just remember to keep your input selector on the automatic input pink color orb option so you can move quickly between multiple sources.

We would say, however, a USB/dual-BNC input/output is likely to yield the most beneficial results given its ability to transmit at a higher rate than optical.


For the review, we opted for a Windows 10 Acer Nitro setup, Roon and Foobar2000. File playback was in FLAC from 44.1K up to DSD512 as well as a selection of video streamed or on external storage.

From the Qutest we have our analog signal initially connected to the Auris HA-2SE and Xi Audio’s Formula S. However, we found that electrostatic amplification and electrostatic headphones to be the most impressive with the M Scaler.

Outside of electrostatic headphones, we focused on using the excellent Diana Phi or Hifiman’s Susvara which are two planar headphones I believe can best capture the way the M Scaler changes the presentation.

We do have one other highly capable upsampling device, the NuPrime CDP-09, which is primarily a DAC and CD Player but does have some switchable sample rates. You will find out direct comparison also on page 2 of the review.

Chord M Scaler Accessories

Accessories & Packaging

Nothing fancy here really, it is more of a traditional Hi-Fi style unboxing experience with a plethora of brown cardboard and gridwork foam bars protecting both the unit and the accessory boxes for transportation. You will not find anything ‘Hollywood’ with the M Scaler unboxing experience.

Chord M Scaler


The accessory line-up for the M Scaler comes in two plain brown rectangular boxes and packed with all the essentials to get the M Scaler up and running. More than that they include a couple of BNC coupler terminated cables which means you can hook up your TT, Qutest, or DAVE right away for maximum performance.

The full accessory line up is as follows:

  • 1.5m 15v 4A Switching power supply
  • IR Remote Control (with 2 non-rechargeable Chord Electronics branded batteries)
  • Dual BNC Cables
  • M Scaler User Manual
  • USB Cable
  • Optical cable

Hang onto that remote. In our testing to date, the remote has been excellent. A product like the M Scaler, whilst not exactly being tucked out of sight is rarely something I want to continually walk across the room or reach for to change sample rates or inputs during listening. The remote takes care of everything for that couch potato lifestyle that we audiophiles wholly embrace.

Click on Page 2 below for Performance Impressions & Comparisons

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17 Responses

  1. Phoenix

    I play from Mac Mini (Roon), directly into my Dynaudio Focus XD 20. Roon’s “parametric EQ” setting seems to “upscale” 16bit to 64 bit floating. Not sure if this is similar? Will M-Scaler really make a huge difference in sound if the starting point is 44Hz/16?

  2. John H

    Thanks for as great review ! I have a TT2 together with Focal Utopia / Stellia and was trying to decide if a loaned HMS was worth it, given it is a huge amount of money on top of what I have already spent. The law of diminishing returns definitely applies but the difference is one, to my ears, worth having …. not a big difference but one which brings voices especially alive ! It seems so close to having a vocalist in your room and you allude to the changes I hear – nothing massive but at the same time significant. I do wonder if the upscaling makes some stuff a bit bright and not as relaxing as ‘lower quality’ but the overall sound is superb.

  3. paul chiu

    Hello Marcus,

    Did you try using other dual BNC coaxial cables other than Chord stock provided?


    • Marcus

      I actually got offered the loan of some expensive ones to try with them but the dealer never pushed through due to COVID19 logistics issues. So in summary, no.

  4. frans callebaut

    is this device only for upscaling streaming sources or for cd’s too ?
    best regards,
    frans callebaut

    • Marcus

      As per page 1, paragraph 5:

      In short, The Hugo M Scaler is a standalone upscaling device that acts as the first port of call for any digital audio source or transport such as a laptop or CD Player.”

  5. Michael John Wadge

    Hello Marcus,

    You will have seen my comments about the M-Scaler. Sadly, my plans to have a home trial have been temporarily scuppered by the old cliche known as Sod’s law. For reasons not yet clear to me, my TT2 has suddenly developed a bad case of hiccups and I know not why. It could be a problem with the PSU or it could be the TT2 itself. I have looked at a thread online and see another owner has had a similar problem. Rob Watts, no less, has responded by saying there could be a faulty PSU and I sincerely hope he is right, as getting a repair of the TT2 done by Chord at this time is impossible. Sadly, the testing of the M-Scaler will now have to wait, so my trusty Mojo/Poly will have to do instead. Things could be worse!

  6. Michael John Wadge

    An interesting review. I have recently changed my Hugo2 to the TT2 and have noticed a big improvement. My best headphones are Focal Utopias and I either use with them my Moon Audio Black Dragon V2cable or my Atlas Zeno, which produces a slightly brighter sound. I am now considering purchasing the M-Scaler. I have two concerns. First, the price, which is obviously considerable. Secondly, nearly all my music is hi res and a lot is in a format I enjoy, DSD, up to and including DSD512, which I can play natively through the TT2 using JRiver Media Center 26 on my laptop. I wonder whether the M- Scaler is really designed to upscale music in DSD format. Can you please comment?

    • Marcus

      Hi, thanks for the feedback. Well, upscaling is relative to where you are starting from in terms of sample rate so the higher your sample rate already is the less of an improvement you will notice. I tend to have a lot at 44.1k 16BIT FLAC so I notice it quite a bit. As for upscaling DSD, it’s converted to PCM before being upscaled. Not sure that’s what you had in mind to achieve optimal resolution.

      • Michael John Wadge

        Hi there,

        Many thanks for the information. I suppose with DSD one always has to accept that it is still very much a niche format and not a great deal of music is actually recorded natively in DSD. I have purchased a lot of DSD format music from NativeDSD, which does produce, at a price, some excellent recordings and the TT2 reproduces them natively. Converting them to PCM as the M-Scaler requires may arguably defeat the whole object. However, I have been promised a home trial soon, so will defer my judgment until a later date.

  7. John

    One of the best descriptions of what the M-Scaler does for your music that I’ve read to date, bravo.

    I noticed two bits that are worth correction.

    1. The output sample rate is not determined by the input type. The manual is very confusing about this. The M-Scaler will upscale any of its inputs to 16x (705.6/768kHz). It’s the optical and single bnc output that are limited to the lower rates, chosen by the OP SR button.

    2. The “Red” OP SR state is equivalent to “bypass” for the upsampling stage. The reason for its existence is to facilitate A/B comparisons. Note that this stage is still subject to the same latency as using upsampling, but the audio itself is not being upsampled.

    • Marcus

      Thanks for the positive feedback. Yes, good spot on the output sampling. I read back and made a few changes to make it clearer on the output caps.

      YUp, the red bypass stage was very useful for examining the differences between ‘regular’ audio and upsampled audio.

    • Leo Kuan

      “The M-Scaler will upscale any of its inputs to 16x (705.6/768kHz). It’s the optical and single bnc output that are limited to the lower rates, chosen by the OP SR button.”

      Shall be “The M-Scaler CAN upscale its inputs UP to 16x” . If input is 192K, it can’t do 16x. Also user can select to upscale only to 8x even input is 44.1K.


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