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Motu M2 Review (Audio Interface)

audiofun

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i know, but RCA have lower dbu comparing to unbalanced plugged TRS, + i want to connect (sometimes) TRS stereo jack with TRS out of Motu M2 (no idea if such cables exist because all i saw - was TRS-2TS)
That won't work. you need both phases to have the doubled voltage.
 

audiofun

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and what if want to just have it connected with unbalanced input, i mean without double voltage?
Then you need a TRS -> RCA cable with R not connected to anything. Or you may be able to find in market a TRS -> dual RCA cable (I'm sure there are plenty of them) and you just leave one RCA (with the inverted signal) unconnected.

Bear in mind that by doing this you may end up with more distortion or dc bias compared to a simple RCA->RCA connection.
 

guildenstern

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Can the M2 serve as a USB DAC (connected to my PC) and output a mono signal (summed L+R) from the headphone jack? That’s what I need – a device that can let me play music from Qobuz and MusicBee on my PC and drive my (fairly sensitive) headphones with a summed mono signal. (Why? Because I only have hearing in one ear.) Thanks for any guidance.
 

Trell

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Can the M2 serve as a USB DAC (connected to my PC) and output a mono signal (summed L+R) from the headphone jack? That’s what I need – a device that can let me play music from Qobuz and MusicBee on my PC and drive my (fairly sensitive) headphones with a summed mono signal. (Why? Because I only have hearing in one ear.) Thanks for any guidance.

No, it can't by itself.
 

mightycicadalord

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Can the M2 serve as a USB DAC (connected to my PC) and output a mono signal (summed L+R) from the headphone jack? That’s what I need – a device that can let me play music from Qobuz and MusicBee on my PC and drive my (fairly sensitive) headphones with a summed mono signal. (Why? Because I only have hearing in one ear.) Thanks for any guidance.

Easier done in software, musicbee can downmix to mono, not sure about quboz.
 

guildenstern

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Easier done in software, musicbee can downmix to mono, not sure about quboz.
Thanks for your reply. True, MusicBee can mix to mono, and its software mixer sounds fine. Qobuz app has no provision for mono output. I can use the Windows PC audio settings to output mono from Qobuz but the result is a significant downgrade in audio quality (yes, I can hear it even with one ear). Perhaps there is some other software solution that would allow mono audio output from the PC that somehow avoids the built-in Windows audio software, which can do mono but does it badly.
 

PeteL

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Can the M2 serve as a USB DAC (connected to my PC) and output a mono signal (summed L+R) from the headphone jack? That’s what I need – a device that can let me play music from Qobuz and MusicBee on my PC and drive my (fairly sensitive) headphones with a summed mono signal. (Why? Because I only have hearing in one ear.) Thanks for any guidance.
Most semi-pro USB interfaces that I used provides a mixer app that makes this very easy. Apparently Motu Doesn't. Or if they do it's advertised poorly because I don't find to it on their site, just third party music production software that are not really suitable for this application. I have used Audients, Tascams, and RME, all of those can do that quite easily without any other outsourced app and configuration.
 

mightycicadalord

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Thanks for your reply. True, MusicBee can mix to mono, and its software mixer sounds fine. Qobuz app has no provision for mono output. I can use the Windows PC audio settings to output mono from Qobuz but the result is a significant downgrade in audio quality (yes, I can hear it even with one ear). Perhaps there is some other software solution that would allow mono audio output from the PC that somehow avoids the built-in Windows audio software, which can do mono but does it badly.

You can try foobar downmix mono but I mean, downmixing to mono is always going to incur a hit in quality. When you try take stereo information and collapse it to mono there's usually wonky cancelations of some elements of the music.
 

PeteL

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You can try foobar downmix mono but I mean, downmixing to mono is always going to incur a hit in quality. When you try take stereo information and collapse it to mono there's usually wonky cancelations of some elements of the music.
If it's the case the mixing engineer didn't do a great job. They should check their mix in mono, think of all Bluetooth speakers, table top radio or really the multitude of cases where correct stereo image is not possible. I am not saying you get the full experience but wonky cancellations can be avoided.
 

guildenstern

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You can try foobar downmix mono but I mean, downmixing to mono is always going to incur a hit in quality. When you try take stereo information and collapse it to mono there's usually wonky cancelations of some elements of the music.
Yes, agreed, downmixing to mono means "a hit in quality," but in my experience some devices, and some software, do a better job than others. The Windows PC downmix to mono results in what sounds to me like a noticeable downgrade. However, if I bypass the Windows audio engine (by way of "WASAPI Exclusive" output setting), and use the "mono" setting in the MusicBee software, I perceive little degradation in audio quality. The same is true of the PC (set to "WASAPI Exclusive") feeding an RME ADI-2 DAC FS with its mono setting on. I was just hoping to find a solution less expensive than the RME. I'll look into foobar, and thanks.
 

mightycicadalord

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If it's the case the mixing engineer didn't do a great job. They should check their mix in mono, think of all Bluetooth speakers, table top radio or really the multitude of cases where correct stereo image is not possible. I am not saying you get the full experience but wonky cancellations can be avoided.

I disagree a lot there. I do mix and write music myself and mono is always a compromise and tracks should IMO be mixed with stereo in mind first. One can get lost in chasing mono compatibility which can result in compromises to the stereo mix which I don't think is worth it. There are plenty of tracks out there, many considered to be excellent mixes by just about everybody, and they still lose entire elements when attempting mono.
 

carmico

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guys, do you think the Motu M2 gonna be an upgrade over my iFi Zen DAC v2 ? (both are balanced)

99% gonna use it as DAC/preamp for my iLoud MTMs

i don't care about ADC , just want better DAC sound quality and the possibility to do volume control within macOS

another thing, the Motu comes handy opening the possibility to use the MTMs mic as line-in to apply room correction using ARC 3 System

i made a topic for this: https://www.audiosciencereview.com/...s-audio-interface-upgrade.31140/#post-1098377
 

Chromatischism

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guys, do you think the Motu M2 gonna be an upgrade over my iFi Zen DAC v2 ? (both are balanced)

99% gonna use it as DAC/preamp for my iLoud MTMs

i don't care about ADC , just want better DAC sound quality and the possibility to do volume control within macOS

another thing, the Motu comes handy opening the possibility to use the MTMs mic as line-in to apply room correction using ARC 3 System

i made a topic for this: https://www.audiosciencereview.com/...s-audio-interface-upgrade.31140/#post-1098377
Was that mic specifically calibrated or is it ok for general use? I'm not sure about that.
 

phoenixsong

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guys, do you think the Motu M2 gonna be an upgrade over my iFi Zen DAC v2 ? (both are balanced)

99% gonna use it as DAC/preamp for my iLoud MTMs

i don't care about ADC , just want better DAC sound quality and the possibility to do volume control within macOS

another thing, the Motu comes handy opening the possibility to use the MTMs mic as line-in to apply room correction using ARC 3 System

i made a topic for this: https://www.audiosciencereview.com/...s-audio-interface-upgrade.31140/#post-1098377
I heard a Zen DAC at the end of 2019 (probably the original?), it sounded pretty bad with all of my own IEMs and also TOTL headphones in the headphone shop where I tried it. Audibly worse than even my Grace Design SDAC and JDS OL DAC which I had at the time. I'm now using the Motu M2; apart from a somewhat weak headphone amp section, the sound quality is at least 2 tiers better than the Zen's. Not sure how much of an improvement the v2 is, but having bought iFi's stuff years ago and seeing the measurements of their various products over and over again since then, I daresay the Motu would be better if you are going for undistorted/transparent sound
 

carmico

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Was that mic specifically calibrated or is it ok for general use? I'm not sure about that.
afaik , the MEMS mic that comes with iLoud MTM is the same mic included with ARC, from IK multimedia website:

ARC System 3 includes a precision-manufactured MEMS room analysis microphone, for the most precise measurements possible. But you can also use generic measurement microphones, and even load a mic calibration file for superior accuracy.

and for the subwoofer:

I have a 2+1 system that includes a subwoofer, how should I measure the room?​



If the subwoofer is handling the crossover and feeding the main speakers, or if you are using an external crossover the system will be seen as a normal 2 channels setup, so you can use ARC 3 without any issue.

ARC 3 will also adjust the level of the LF range matching it perfectly with the main speakers.

so seems like the M2 gonna do the job

I heard a Zen DAC at the end of 2019 (probably the original?), it sounded pretty bad with all of my own IEMs and also TOTL headphones in the headphone shop where I tried it. Audibly worse than even my Grace Design SDAC and JDS OL DAC which I had at the time. I'm now using the Motu M2; apart from a somewhat weak headphone amp section, the sound quality is at least 2 tiers better than the Zen's. Not sure how much of an improvement the v2 is, but having bought iFi's stuff years ago and seeing the measurements of their various products over and over again since then, I daresay the Motu would be better if you are going for undistorted/transparent sound

well, i don't use the headphone amp that much to be honestly, because when need headphone i use the Airpods Pro with bluetooth because way more pratical, even if i have iem Shure SE215 and Beyerdynamic DT770 80ohm too

i don't need ADC because i don't record instruments or things like that, i just want a sweet DAC for multimedia use (music, videos, etc)

seems like the M2 fits exactly what i need , the other choice could be the Topping D10 Balanced , but no mic input for ARC3 (i could grab an usb UMIK mic and go REW or DIRAC way) , and don't know if the D10B is okay with macOS volume control (probably with Soundsource yes, because the Zen DAC can't becasue Analog Volume control knob)
 

phoenixsong

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afaik , the MEMS mic that comes with iLoud MTM is the same mic included with ARC, from IK multimedia website:



and for the subwoofer:



so seems like the M2 gonna do the job



well, i don't use the headphone amp that much to be honestly, because when need headphone i use the Airpods Pro with bluetooth because way more pratical, even if i have iem Shure SE215 and Beyerdynamic DT770 80ohm too

i don't need ADC because i don't record instruments or things like that, i just want a sweet DAC for multimedia use (music, videos, etc)

seems like the M2 fits exactly what i need , the other choice could be the Topping D10 Balanced , but no mic input for ARC3 (i could grab an usb UMIK mic and go REW or DIRAC way) , and don't know if the D10B is okay with macOS volume control (probably with Soundsource yes, because the Zen DAC can't becasue Analog Volume control knob)
Yeah I've never used mics before I got the M2, but I love its versatility so much that I got myself 2 Behringer XM8500, 1 SE Electronics V7X, 1 Neat Worker Bee Original, 1 Rode NT1 and 2 MXL CR21 since I got it maybe a year and a half ago :p
 

BeerBear

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I was pleasantly surprised to see a proper reconstruction filter that chops everything off at 22 kHz rather than the common 24 kHz:
index.php
Has this filter performance been confirmed anywhere else?
Because it really looks too good to be true, especially when the Motu M4, which has the same DAC, doesn't perform like this.

Disclaimer: my speculations, not necessarily correct. The tests were done with ASIO4ALL, if you see all other interfaces (non-DAC) measurements they were all done with dedicated ASIO drivers, including M4.
View attachment 112919

M2 also uses ES9016s.
https://prosound.ixbt.com/interfaces/motu-m2.shtml

Even higher-end chips can't achieve this level of steepness and attenuation.
index.php


As well as non-Pro chips:
index.php

index.php


You can see that the filter really struggled to achieve this level of steepness, which scarifies passband ripple and stopband attenuation.

But the filter shape looks pretty similar to the one on Windows mixer (the third screenshot):
https://www.audiosciencereview.com/...r-mirror-images-short-study.20318/post-674646

Windows mixer is "bad" when compared to something like SoX with 160dB+ attenuation, and when using non-integer resampling ratios, but it is more precise than typical on-chip filters which only use integer ratios. Played through Firefox rather than dedicated audio players to 100% avoid any potential hidden high quality SRC within the player.

That said, I tried ASIO4ALL on the Realtek but cannot reproduce the same result, it is only achievable when playing through Windows mixer. ASIO4ALL's built-in SRC performed pretty poor in my tests.
Interesting, this looks like it might explain it.

I saw a similar filter performance in the Ultralite-Mk5 review, which makes me wonder if MOTU hasn't come up some magic after all.
But the Ultralite-Mk5 uses the ES9026PRO DAC and, looking at the specs for the filters, I don't see one with such a steep response:

ES9026PRO filters.png

The only one that promises -100dB at 0.5fs is the "Brickwall", but it's already at -3dB at 0.451fs (~19.9kHz at 44.1k sample rate).
Here's the whole datasheet for ES9026PRO.

It's possible that I missed something or that I don't understand how this works. But so far it looks like it's probably a mistake to me.
I've been told that you can't have such steep filtering with low latency and these MOTUs are rather low latency devices (although not quite with the lowest latencies in this market segment).
 
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Bamboszek

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MOTU has rather powerful DSP FPGA already so we can guess that low pass filter is done on FPGA side instead using filters build-in DAC chip.
 
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