Motu M4 Audio Interface Review

[Chris M]

I'm currently trying to get the Raspberry Pi 4 running with Moode 7.21. So far without success. Kodi on Raspberry OS doesn't run either.

 

[jdubs]

Yeah, I don't think Moode works with the M4 yet. Hopefully it will in the (near?) future!!!

-Jim

 

[137tmxth]

Just got a M4 after about a month of waiting...

It appears to be the new version, bottom says "Made in China", not "Assembled in USA". On my Linux machine, audio output from computer was glitching very badly until I updated the kernel from 5.8 to 5.12... even though according to information on the interwebs, 5.8 was supposed to be already the first version which works flawlessly with the M4.

On my Windows machine, it seems to be working fine so far (but I haven't really tried to stress it yet, been just listening to music and fiddling with the controls) except that it almost always resets itself (or loses power momentarily?) if I toggle the 48V power on mic inputs...

I have no plans to actually use microphones which require phantom power with this box, but I still wonder if I should return it while it's in the return period... it does not seem to do this with my other machine, so it is probably some kind of a compatibility problem between the box and the mobo in the other machine, but on the other hand, there are no measurements to be found for the new rev anywhere either so who knows how it compares. According to info on the interwebs (elsewhere on this forum and a certain Russian forum), they have changed some of the chips at the very least.

 

[somebodyelse]

There were some updates from someone with a MOTU email address to improve M series compatibility. I don't remember if it was 5.10 or 5.11 they went into.

 

[137tmxth]

There were some updates from someone with a MOTU email address to improve M series compatibility. I don't remember if it was 5.10 or 5.11 they went into.

Yes, but AFAIK the original hardware revision should have fully worked with kernel 5.8 already. So I mentioned that just to emphasize that I indeed got a newer variant of the unit.

Other details which identify the new rev besides requiring a newer kernel if using it in Linux and it being assembled in China instead of USA seem to be:

• the new units all come with firmware 2.x out of the box which isn't even available as a download on Motu's website yet
• different USB ID
• doesn't work at all with the older Win7 compatible releases of Motu's Windows driver

(edit: and, as mentioned elsewhere, the chips have changed; eg. main controller chip is now a NXP part instead of XMOS, DAC is now a ES9026pro instead of a ES9016S, the board design also appears to have changed significantly based on photos)

In the end I deciced to keep it, even though there is also a slight issue with the big monitor volume knob which however doesn't seem to affect it's function in any way (looks like other people have returned multiple units for way less, lol). Hopefully I don't live to regeret it.

Certainly I can't hear any obvious problems with the inputs or outputs, but what if the eventual measurements of the new rev show that I could have got the same quality with less money. Only reason I went for the M4 instead of one of the cheaper interfaces I looked at (which would also have had SPDIF inputs) in the first place was the good-to-excellent measurements and reviews it (well, the original hardware rev) scored pretty much everywhere.

 

[hira]

The design has changed.
DAC ES9016S>ES9026PRO
USB XMOS XU216>LPC552x?
OPAMP OPA1688?>OPA1678
Various other

Quote source

 

[137tmxth]

The design has changed.

Indeed it has. Seems so far the new chips are all higher specced than the old ones were? Still, it's always at least a theoretical possibility that they have made a mistake somewhere with the new design, which would make it perform worse than the old one regardless.

Hopefully there will be measurements / reviews of the new version soon. I'd gladly send mine to be measured, but unfortunately I live in a country with relatively high fees for mailing pretty much anything outside the borders...

 

[kukocz]

How to differentiate new version from the old one?

 

[137tmxth]

How to differentiate new version from the old one?

I listed some ways in a post before the one with the embedded Youtube video which was visible for a while, but it went back to the new users' moderation queue after I edited it. Easiest is probably to look at the sticker on bottom, it seems so far all the old version units are "Assembled in USA" while the newer ones are "Made in China".

The new ones also have firmware version 2.x out of the box (not even available for separate download from Motu's website yet, probably 1.x is only for XMOS and 2.x is only for NXP chip or both), and if I understood the discussion on a Russian forum through Google Translate correctly, different USB hardware ID.

If you open the box, the older ones seem to all have a green PCB while the newer ones have a blue board instead.

 

[AnalogSteph]

Interesting, interesting. So I guess they ran out of their stock of ES9016s first, unlike the AK5554 I would have expected. ES9026PRO is just a more modern replacement with more filter options and stuff. The blue PCB may also indicate that they had to farm these out to another supplier, perhaps in the wake of the pandemic. With rev 2 now out, there is some hope that the stock situation improves.

Also, opamps (except headphone) are just OPA1678s now? The first rev also had some 4580s I think.

A bit of an oopsie there with the coupling caps on the instrument input. -1 dB at ~32 Hz --> -3 dB at 16 Hz with a 1 Megohm input impedance indicates a value of 10 nF. Expect a fair bit of 1/f noise in this input unless upgraded.

I see no special provisions for capacitive load driving on the line-in ADC driver... if the rev 1 was the same that would certainly explain the ultrasonic peaking observed by Amir. And with the THS4521 being a low power part, the rise in high-frequency harmonic distortion is no major surprise either.

For a design that doesn't absolutely use any more parts and power than it absolutely has to, this is doing pretty well for itself. The hiccup when turning on phantom power is not pretty though and may point to something being marginal in the USB power department. I might try another USB cable... I don't know whether it was this interface where people said the supplied one was crap but it may have been. The joys of bus-powered USB interfaces...

 

[phoenixdogfan]

Just bought one of these to use as an A to D converter. Impossible to tell if it's version 1 or two without opening it up, I think. No indicator on the box or case where it was made. Is there a way of identifying by Serial number? I'd kind of like to know, but I don't feel like opening up the case.

 

[137tmxth]

Just bought one of these to use as an A to D converter. Impossible to tell if it's version 1 or two without opening it up, I think. No indicator on the box or case where it was made. Is there a way of identifying by Serial number? I'd kind of like to know, but I don't feel like opening up the case.

If you are using Windows or MacOS, install Motu's driver and check whether the firmware version is 1.x or 2.x.

 

[jdubs]

Hey all, is anyone using the M4 via Wasapi in HQPlayer? Not sure how to get it to be in Wasapi exclusive mode.

Thanks,
Jim

 

[drake5000]

Hopefully there will be measurements / reviews of the new version soon. I'd gladly send mine to be measured, but unfortunately I live in a country with relatively high fees for mailing pretty much anything outside the borders...

I would love to see new revision’s measurements as well

 

[137tmxth]

Hey all, is anyone using the M4 via Wasapi in HQPlayer? Not sure how to get it to be in Wasapi exclusive mode.

WASAPI exclusive mode doesn't work for me either in any program. You may have to use ASIO if you need something better than WASAPI shared mode.

Btw., WASAPI exclusive does mode doesn't work at all for a couple of people I know who are using Steinberg interfaces either, or for me using my Windows machine's mobo's integrated Realtek audio hardware (with a Microsoft driver), so MOTU isn't alone in this.

And yes, we have tried closing all programs which could possibly be using the sound device, even killing explorer.exe via task manager, it still simply does not work at all, no program can ever successfully open the device in exclusive mode. (also yes, sound control panel settings have been set to allow exclusive mode)

I heard exclusive mode used to once work for at least one of the people I asked, so perhaps Microsoft has broken something in one of their usual garbage Win10 updates...

Another thing which doesn't work on the MOTU but does work on my mobo's Realtek (with the MS driver) is WASAPI low latency mode (<10ms buffer, it can go down to 2.5ms). But again, MOTU isn't alone in this, at least Steinberg's driver doesn't bother with supporting it either, I guess they assume everyone who wants low latency is going to use ASIO anyway.

 

[AnalogSteph]

Btw., WASAPI exclusive does mode doesn't work at all for a couple of people I know who are using Steinberg interfaces either, or for me using my Windows machine's mobo's integrated Realtek audio hardware (with a Microsoft driver), so MOTU isn't alone in this.

Peculiar.

I have some new machines to set up anyway tomorrow, will have to try this. In case it matters, Cortana will remain disabled.

 

[stemfencer]

Apologies if this is not the correct thread, thought it seemed more relevant here than new post.

What would be the next step change up from this, taking it up a level since the M4 seems to occupy most recommendations and performance? Additionally trying to find something with great to excellent headphone output, something not really found <$1000 from research.

Seems like RME Babyfacy still requires an external headphone amp if want critical listening, and the Universal Audio apollo seem like a bit of waste of money if not going to invest in their plug-in ecosystem. Do we have to go up to something like RME Fireface UCX II to find an integrated box that has noticably superior converters, preamps, output amps etc?

 

[Trell]

Apologies if this is not the correct thread, thought it seemed more relevant here than new post.

What would be the next step change up from this, taking it up a level since the M4 seems to occupy most recommendations and performance? Additionally trying to find something with great to excellent headphone output, something not really found <$1000 from research.

Seems like RME Babyfacy still requires an external headphone amp if want critical listening, and the Universal Audio apollo seem like a bit of waste of money if not going to invest in their plug-in ecosystem. Do we have to go up to something like RME Fireface UCX II to find an integrated box that has noticably superior converters, preamps, output amps etc?

It's all about features and connectivity after the point of inaudibility for most of us. The M4 is a pretty nice inexpensive interface and if you find the headphone out is too limited for you there is the option for an external headphone amplifier.

 

[DJBonoBobo]

Do we have to go up to something like RME Fireface UCX II to find an integrated box that has noticably superior converters, preamps, output amps etc?

I gave away a Motu M4 and bought an RME UCX II - not for reasons of SQ but simply because the Motu annoyed me. I had issues with ground loop and some driver hickups. The RME just works. Additionally, TotalMix FX is dope. Absolutely worth the money, even if i only use a fraction of it´s functionality.
"Who buys cheap, buys twice" was true in my case.

 

[Trell]

I gave away a Motu M4 and bought an RME UCX II - not for reasons of SQ but simply because the Motu annoyed me. I had issues with ground loop and some driver hickups. The RME just works. Additionally, TotalMix FX is dope. Absolutely worth the money, even if i only use a fraction of it´s functionality.
"Who buys cheap, buys twice" was true in my case.

If the RME ADI-2 Pro had a mic preamp I would have bought instead of the ADI-2 DAC FS while using the M2 for mic purposes.