Motu M4 Audio Interface Review

[AnalogSteph]

Instead of jumping through hoops like that, why not feed the external amp from the headphone output to begin with?

 

[Jimbomebub]

Does anyone have an idea of the effect that the main large Volume Knob (Monitor) has on distortion levels through the unbalanced line-out (red and white) outputs? I am feeding my Motu M4 into a Schiit Magni 3+ and I am wondering if having the Monitor knob cranked would cause an increase in THD in the signal chain.

Can someone answer this for me? I'd like to keep the Monitor knob maxed out in order to reduce the gain on my Magni, as I currently have to run it at round 2 o'clock on high gain. If I max the monitor knob on the Motu, I can keep the Schiit around 12 o'clock but again I am afraid I am introducing distortion by having the knob completely maxed out. I understand I may sound stupid asking this question. Thanks.

 

[antcollinet]

Does anyone have an idea of the effect that the main large Volume Knob (Monitor) has on distortion levels through the unbalanced line-out (red and white) outputs? I am feeding my Motu M4 into a Schiit Magni 3+ and I am wondering if having the Monitor knob cranked would cause an increase in THD in the signal chain.

Can someone answer this for me? I'd like to keep the Monitor knob maxed out in order to reduce the gain on my Magni, as I currently have to run it at round 2 o'clock on high gain. If I max the monitor knob on the Motu, I can keep the Schiit around 12 o'clock but again I am afraid I am introducing distortion by having the knob completely maxed out. I understand I may sound stupid asking this question. Thanks.

Bit difficult to answer without knowing exactly what the monitor knob does.

I'd assume it is just the volume control for the headphone (monitor) output - or does it adjust the other analogue outputs also?

EIther way - the only way it will introduce distortion is if the outputs reach a voltage limit, or if the voltage output from the M4 overdrives whatever is the next device down the stage. For that you would need to understand the gain staging of the M4 and the destination amp. It is quite unlikely the amp will be over driven, since you are then turning down the level on that with it's own volume control.

Having said that - if you are not hearing distortion, then I'd suggest it is not something to worry about.

 

[AnalogSteph]

AFAIR, M4 monitor volume affects the Monitor 1/2 outputs only (and it's a digital volume control). Headphone is separate, 3/4 is fixed. I would expect unbalanced line-out level to be 6 dB below balanced level, i.e. +10 dBu max (~2.45 Vrms). This is close enough to consumer CD player level that you aren't very likely to be clipping the Magni's input.

 

[Buckster]

checked earlier and a new firmware version was released for the V2 of the M4 30/11 that I'd not seen before today

new firmware is 2.03. No change-log

 

[PlateMail]

I was hoping I could use this device with Dirac Live Bass control, using 1-2 for mains and 3-4 to subwoofers. But maybe that isn't possible as the Motu m4 displays as multiple devices in Windows. Is anyone using this device in windows using software crossover and delays for integrating subwoofers in a stereo setup?

 

[peng]

I have the same question as PlateMail. Would like to use it with my Dirac Live PC standalone version to try DLBC, so I need a discrete subwoofer channel to integrate with the left/right speakers. Can someone please tell me if I can just run it as an USB DAC, that is, from my windows 10 laptop USB port to the Motu's USB-c input port and it windows 10 can be configure to output 2.1, that is discrete channel for the left, right and sub? If that works, then I will connect the Motu's output 1,2 to my 2 channel preamp and output 3, or 4 to my subwoofer power amp. I tried asking Motu the question, but it seems that I have create an account with them first; and I assume I can only do so if I have already owned the product.

 

[PlateMail]

I have the same question as PlateMail. Would like to use it with my Dirac Live PC standalone version to try DLBC, so I need a discrete subwoofer channel to integrate with the left/right speakers. Can someone please tell me if I can just run it as an USB DAC, that is, from my windows 10 laptop USB port to the Motu's USB-c input port and it windows 10 can be configure to output 2.1, that is discrete channel for the left, right and sub? If that works, then I will connect the Motu's output 1,2 to my 2 channel preamp and output 3, or 4 to my subwoofer power amp. I tried asking Motu the question, but it seems that I have create an account with them first; and I assume I can only do so if I have already owned the product.

I don't think this is possible with the current drivers for the Motu M4. Windows shows the outputs 1-2 and 3-4 as different devices, and you can't aggregate these. You can only add subwoofers in DLBC from the same device feeding the main speakers.

I had an idea doing the crossover using a combination of Voicemeeter Banana and Equalizer APO and make DIRAC treat this as a single speaker. This quickly became pretty complex and I gave up.

I also had the idea of using my integrated amp for mains and connecting the subwoofer for the other outputs from the Motu, but this setup would require using Windows for volume control. Instead i will use my AVR as preamp using the 7.1 analogue input in pure direct and use my integrated amplifiers HT bypass. I will then use my AVR for volume control.

I will give up DLBC for now with Motu 4. I guess an Asus Xonar U7 MKII or a GIGAPORT eX should work. Both are quite cheap and I might buy one of these just to try and compare.

Update: It seems like when using ASIO in Dirac Live Processor the 4 channels is listed under the same device. This never worked for me before, but after uninstalling ASIO4ALL this option became available again.

 

[peng]

I don't think this is possible with the current drivers for the Motu M4. Windows shows the outputs 1-2 and 3-4 as different devices, and you can't aggregate these. You can only add subwoofers in DLBC from the same device feeding the main speakers.

I had an idea doing the crossover using a combination of Voicemeeter Banana and Equalizer APO and make DIRAC treat this as a single speaker. This quickly became pretty complex and I gave up.

I also had the idea of using my integrated amp for mains and connecting the subwoofer for the other outputs from the Motu, but this setup would require using Windows for volume control. Instead i will use my AVR as preamp using the 7.1 analogue input in pure direct and use my integrated amplifiers HT bypass. I will then use my AVR for volume control.

I will give up DLBC for now with Motu 4. I guess an Asus Xonar U7 MKII or a GIGAPORT eX should work. Both are quite cheap and I might buy one of these just to try and compare.

Do you think the Topping dac will work, such that windows can use it for 2.1 implementation simply using the USB ports? Too bad there don't seem to be any 3 or 4 channel usb dac for under $350 that can do the job. I guess I can only test DLBC on my HT setup for now and if it works well then figure a way to do it in my two channel system.

Topping DM7

https://www.amazon.com/Topping-DM7-USB-DAC-Multi-Channel/dp/B0B6BLF91P/ref=sr_1_1?crid=31XMBP7FBGL41&keywords=topping%2Bdm7&qid=1672167373&sprefix=topping%2Bdm7%2Caps%2C77&sr=8-1&th=1

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[PlateMail]

An update on this:

Using ASIO as Audio Device Type in Dirac Live Processor the MOTU now lists all 4 channels for the device, and I can now choose all 4 channels and dedicate these as subwoofer channels. I still haven't done any calibration but just looking at the VU meters on the M4 running the volume calibration in Dirac Live 3 it seems like it's working.

 

[peng]

An update on this:

Using ASIO as Audio Device Type in Dirac Live Processor the MOTU now lists all 4 channels for the device, and I can now choose all 4 channels and dedicate these as subwoofer channels. I still haven't done any calibration but just looking at the VU meters on the M4 running the volume calibration in Dirac Live 3 it seems like it's working.

Great, please updating this when you have more news. Again, I just want to make sure connection below will work with Dirac Live PC standalone version + DLBC:

- Windows 10 laptop USB to MOTU M4 USB-C port
- MOTU M4 output 1,2 to preamp analog inputs L, R
- MOTU M4 output 3, or 4, to subwoofer amp RCA input

Then

- un Dirac+DLBC on the laptop and calibrate
- After that, play music via JRiver, or stream from Amazon unlimited, Tidal etc., from the windows 10 lap top.

Not much to ask right.

Thanks again for sharing your experience with the M4.

 

[AudioKC]

Seems like a great device for office setup with Dirac Live Bass Control. Considering getting it and testing it. Now I run virtual multichannel DAC based on Apple USB C dongles (lol).

 

[PlateMail]

- Windows 10 laptop USB to MOTU M4 USB-C port
- MOTU M4 output 1,2 to preamp analog inputs L, R
- MOTU M4 output 3, or 4, to subwoofer amp RCA input

Will you use Windows for volume control?

 

[peng]

Will you use Windows for volume control?

I would prefer not to if I can figure out a way. For now, I would say yes, use windows. At least for the beta test.

 

[bequietjk]

I just saw the Motu M6! Is that new? Would love to see that on the test bench.

 

[trl]

Based purely on their specs, I see not much of a difference, just 1dB better for the Line In on M6:

https://motu.com/en-us/products/m-series/m6/specs/ vs. https://motu.com/de/products/m-series/m4/specs/

However, looking forward for someone to have it on its bench too.

 

[MCH]

I was hoping for a 6in/6out interface, but it is double the price vs the M4 and has just 2 more channels in and same 4 out.... If nothing else has changed, doesn't seem a great value...

 

[PlateMail]

Great, please updating this when you have more news. Again, I just want to make sure connection below will work with Dirac Live PC standalone version + DLBC:

- Windows 10 laptop USB to MOTU M4 USB-C port
- MOTU M4 output 1,2 to preamp analog inputs L, R
- MOTU M4 output 3, or 4, to subwoofer amp RCA input

Then

- un Dirac+DLBC on the laptop and calibrate
- After that, play music via JRiver, or stream from Amazon unlimited, Tidal etc., from the windows 10 lap top.

Not much to ask right.

Thanks again for sharing your experience with the M4.

Now I've had some time to connect everything and try a calibration. The MOTU4 is connected to a USB port on my PC running Windows 10. I've connected all outputs from the MOTU4 to my AVR multichannel inputs. The AVR is only used as preamp as the L+R is connected to an Arcam A32 in HT bypass mode and the subwoofer out is connected to an SVS SB2000.

I've configured Dirac to use MOTU4 in ASIO mode and I've tested Foobar2000 and Squeezelite-X and configured those to use the virtual Dirac soundcard and everything works. I get output to left, right and subwoofer and I can use my AVR's volume control.

I only did a quick calibration with 3 measuring points and I've only verified that it works and have no comments yet on the results.

 

[cajadas]

Is there any chance that Apogee Duet 2 can sound any better than MOTU M4?

 

[antcollinet]

Is there any chance that Apogee Duet 2 can sound any better than MOTU M4?

Not really.

All of the measurements of the Motu show noise/distortion etc lower than our ability to hear. Even if the Duet measures better, you won't hear the difference.