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Motu M4 Audio Interface Review

Little question:

Inputs 3 and 4 on my M4 are already taken by my modular system. If I want to connect an Analog Rytm to my interface, I still have inputs 1 and 2. Do I just need to connect two 6.35 mm jack cables between the Rytm's main outputs and the M4's inputs 1 and 2 for it to work in stereo?

Of course I'd have to set up the stereo outputs on Ableton Live.

Is it better to use balanced or unbalanced cables? Should I be careful not to press a certain button (48V or another) to avoid destroying the Rytm? I'm not sure about the last question, but I think I heard that once.

Thank you!
 
Guys, how to be sure if the M4 knows that it works with line signal? I'm talking about front combo jack line-in.

What I'm doing; Engl Fireball 25 line-out (0 db) -> instrumental cable -> front line-in of M4.
What's the case; If I set Master level high (let say 12 o'clock) and Lead Volume this same on FB25, in DAW I get -3db peak recording level, is too high for mixing. I can't set volumes on FB25 lower because of change in sound.
So,
1. If the M4 automaticly knows that the line-in is connected? (there is no button on M4c like INST or something to set on M4).
2. Is there any way to control power on line-in connection? (some loud box with attentuator or something?)

Thank you!
 
Guys, how to be sure if the M4 knows that it works with line signal? I'm talking about front combo jack line-in.

What I'm doing; Engl Fireball 25 line-out (0 db) -> instrumental cable -> front line-in of M4.
What's the case; If I set Master level high (let say 12 o'clock) and Lead Volume this same on FB25, in DAW I get -3db peak recording level, is too high for mixing. I can't set volumes on FB25 lower because of change in sound.
So,
1. If the M4 automaticly knows that the line-in is connected? (there is no button on M4c like INST or something to set on M4).
2. Is there any way to control power on line-in connection? (some loud box with attentuator or something?)

Thank you!

the DAW doesn't care for the level. just make sure to have no red light on the input LEDs and you are good. without buttons, it probably bypasses the pre-amps when using TS/TRS on inputs 1/2
 
Привет, у меня топпинг а90 дискретный, что купить?
Motu m4 и подключить trs(motu) к xlr(a90) или топпинг d90 и подключить xlr(d90) к xlr(a90)?
Будет ли разница в звуке? Что будет лучше для audeze lcd-x?
Есть ли какие-либо другие соображения, которые мне не хватает, или рекомендации?
 
Привет, у меня топпинг а90 дискретный, что купить?
Motu m4 и подключить trs(motu) к xlr(a90) или топпинг d90 и подключить xlr(d90) к xlr(a90)?
Будет ли разница в звуке? Что будет лучше для audeze lcd-x?
Есть ли какие-либо другие соображения, которые мне не хватает, или рекомендации?
* grabbing popcorn
 
Greetings - I recently have been considering using my M4 to take some measurements of some lesser performing audio gear. I want
to use it both as a signal generator and capture device. When I did some initial tests I was a little surprised by the results -
I went from the Line Out (3L / unbalanced) to Line In (3L / unbalanced). At full scale I measured the output of Line Out
at 2.508 v and I fed that directly into the Line In. I measured SINAD and THD+N and was expecting to see numbers close to
the worst case of DAC and ADC (according to Amir's measurement), but in this case my results pretty much exactly
matched Amir's DAC result. I was surprised to not see numbers more resembling the ADC's. I guess the only thing
I am not 100% sure about is what level Amir's drives the ADC with?

1704644642197.png
 
This would have been a more perfect interface if:
  1. Volume knob for main outs or switchable source for headphone out (channels 1-2 or 3-4)
  2. Toslink/digital in (so it can work as a standalone DAC)
  3. Digital mixer to tame the main outs
Still trying to find a good interface w/ independent volume for headphone and main outs in a small format. M4 came close! 2 and 3 are linked, they both would require the M series to have minimal DSP onboard to support an embedded mixer. So my upgradetitis will subside and I shall continue to use my usbpre2 :)
 
Greetings - I recently have been considering using my M4 to take some measurements of some lesser performing audio gear. I want
to use it both as a signal generator and capture device. When I did some initial tests I was a little surprised by the results -
I went from the Line Out (3L / unbalanced) to Line In (3L / unbalanced). At full scale I measured the output of Line Out
at 2.508 v and I fed that directly into the Line In. I measured SINAD and THD+N and was expecting to see numbers close to
the worst case of DAC and ADC (according to Amir's measurement), but in this case my results pretty much exactly
matched Amir's DAC result. I was surprised to not see numbers more resembling the ADC's. I guess the only thing
I am not 100% sure about is what level Amir's drives the ADC with?

View attachment 340325
When you test things this way you don't decouple ADC from DAC. To test AD and DA independently you need to drive the ADC using an external calibrated and measuring-grade device and record the DAC's output using the same or similar device.
 
My m4 came in the mail yesterday and I got a chance to test it out.

Sure enough, the rear line inputs are hard panned for direct monitoring.

I probably could have lived with that, if not for a much bigger problem: weird digital crackling when adjusting the monitor mix knob or preamp gain knobs while playing an instrument plugged into any of the inputs and direct monitoring.

I tried reinstalling the firmware, changing sample rates, but couldn’t get the weird crackling to stop, so I’m sending the m4 back. Too bad because I like the big bright meter display, solid build with metal knobs, power switch, and excellent audio quality (when not direct monitoring).

I probably got a bad one but it’s discouraging. Has anyone else had this issue?

Pretty sure this was the newer MIC version.
I doubt it would help now, but I've had this with several different high and low-end interfaces over the years, and it has been a driver-related issue linked to latency. When buffers are set too low it may be ok at the volume currently set, but going to adjust the volume causes a digital crackling and sometimes requires refreshing things in a mix session. It is tied to latency when that happens more because of system bus/buffering. Those things aren't an issue as much these days with much faster RAM and front-side bus chache much faster (usually) but can still happen if you ever run into having enough bandwidth from too many USBs sharing a hub.
 
Looking forward to using this as my interface and not have to worry myself about the headphone out as long as it is loud enough
 
I am on the fence on getting the M4 as a primary audio interface first and audio fidelity second.

After all these years since launching, the aging(?) M4 has some competitions near the price point.

Should I still be thinking about the M4?

What made you guys brought the M4?
 
I bought the M2 otherwise I would have bought the M4 or M6. I bought it for music fidelity but also use it for all of my audio and video mixing needs. I think the usb c port is questionable on the M2, might differ on the M4. At the end of the day I think it's a good device. My interest in the M6 is solely for the purpose of inputs being on the back of the unit which is HUGE for desk space.
 
After all these years since launching, the aging(?) M4 has some competitions near the price point.

Like what? Aren't the competitors aging as well? (Focusrite?) The biggest issue happens when the manufacture stops updating the drivers for the device. As soon as the manufacture stops producing the device (probably because of parts availability), they tend to stop any required driver maintenance / updates too.
 
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for my hobbystudio ; I'm a windows guy & previously had thought of MOTU as a MAC-specific interface outfit. 4 yrs ago bought an M2 and have been w/o a hiccup. Sounds great.
Cheers
 
Like what? Aren't the competitors aging as well? (Focusrite?) The biggest issue happens when the manufacture stops updating the drivers for the device. As soon as the manufacture stops producing the device (probably because of parts availability), they tend to stop any required driver maintenance / updates too.
Focusrite-wise, models prices near the M4, I think they got updated versions. Hence, I wonder if MOTU would do the same since silicon chips, these days, improve a lot every four years, yet nothing have changed with the M# series.
 
Does anyone know the Line Input 3 and 4 at the back of the M4 go directly to ADC or they go to the interface pre-amp first then ADC?

I read the User's Guide but it stated connect keyboards and other line-level audios there without explicatively stating the specific.
 
Does anyone know the Line Input 3 and 4 at the back of the M4 go directly to ADC or they go to the interface pre-amp first then ADC?

I read the User's Guide but it stated connect keyboards and other line-level audios there without explicatively stating the specific.

I don't know what you mean. The adjustable preamps are only available on the front 1/2 (front gain knobs up to +60db). Input 3/4 are fixed gain inputs as spec'd in the manual for sure.
 
Some audio interfaces, such as the SSL 12 and Audient Id 22 & 24, have specified inputs that skip the interface's amp and straight to the ADC as indicated in their manuals. MOTU does not have that hard written in the manual, but do have a paragraph that somewhat alludes to it on a page. I am ask if others know for sure.
 

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