M2 & M4 iOS Compatibility 2021 iPad Pro (M1 USB-C)

[tbwnm]

Is anyone using the M2 on an iOS device? Specifically; a 2021 iPad Pro (M1 USB -C) running Garage Band? The 2021 iPad Pro should also be able to provide buss power to the M2 from the USB C. Trying to decide between the M2, the Audient ID4 and the Focusrite Scarlett Solo 3rd edition (which from my research are compatible).

[stubbsonic]

That's a good question. I ran into a snag with a non-pro iPad, and found out the hard way that the right USB hub was required to use it with iOS.

Having to use a USB hub is kind of the "fine print" of MOTU's compatibility claim. Hopefully, someone can come on and report if it works hublessly. If not, and those other options do work hublessly, that might influence your decision.

There were other little conditions, like the order of operations in terms of powering on, and connecting cables in the right order. (I don't recall, but if you need that info, I can search and find that thread. It's kind of a long one, but I'd find the info pretty fast.-- As an aside, I've had trouble finding closed TechLinks in the past. Hopefully, MOTU is keeping them up there longer now.).

[mikehalloran]

All three use the same chip.

The M2 is the only one with a) two CombiJacks and mic preamps, b) MIDI c) full metering and d) more flexible monitor options.

There are many on the iPad Music Facebook page using the M2 without problems. The potential issue is bus power with phantom power on and both mic pres active. That's more juice than the others need with their single mic pre. The USB-C M1 iPad Pro supplies more bus power than previous iPads. Whether or not you'll need a powered hub with may depend on your uses and anything else you are connecting such as a keyboard (USB MIDI keyboards connect via a hub, not the M2). MOTU does not offer an interface as feature-poor as the other two you are considering.

[tbwnm]

Thanks for the reply(s). I'll sign up to the iPad Music Facebook group. I have been using DP hardware and software for hundreds of years now and I'm looking to set up a mini composing/songwriting/project studio for my daughter who is 14 (she sings and writes songs). She already had the 2021 iPad Pro and is familiar with Garage Band and I would like to use the M2 as the audio interface if it works seamlessly. The KRK Rokit 5's seem like a good choice for monitors.

[tbwnm]

Other factors to consider between the MOTU M2/M4, the Audient ID4/14 MK II and the Focusrite Scarlet Solo 3rd Gen/2i2 3rd Gen is how quiet the preamps are when using a gain hungry mic and which interface actually has a USB 3 connection that will support additional power and data transfer rates. Although the superior metering options on the M2/M4 is appealing, it does not feature a USB3 connection (and from what I have read the M2/M4 is also on the nosier side). The only interface that has a USB 3 connection is the Audient ID4/14 MK II. Given that the 2021 iPad Pro I'm connecting to has a Thunderbolt/USB 3/4 compatible connector that can take advantage of both the additional power (which among other things is needed for true phantom power operation over the USB bus) as well higher data transfer rates (which from my research effects the overall performance/sonic performance specifically when it comes to the headphone outputs), the Audient makes the most sense for my purposes.If I was connecting to a desktop/laptop and not the iPad Pro then the USB 2 on the other interfaces would be just fine. Still need to decide if it's worth the extra $100 ($299) to go with the iD14 vs the iD4.

[mikehalloran]

Other factors to consider between the MOTU M2/M4, the Audient ID4/14 MK II and the Focusrite Scarlet Solo 3rd Gen/2i2 3rd Gen is how quiet the preamps are when using a gain hungry mic and which interface actually has a USB 3 connection that will support additional power and data transfer rates. Although the superior metering options on the M2/M4 is appealing, it does not feature a USB3 connection (and from what I have read the M2/M4 is also on the nosier side). The only interface that has a USB 3 connection is the Audient ID4/14 MK II. Given that the 2021 iPad Pro I'm connecting to has a Thunderbolt/USB 3/4 compatible connector that can take advantage of both the additional power (which among other things is needed for true phantom power operation over the USB bus) as well higher data transfer rates (which from my research effects the overall performance/sonic performance specifically when it comes to the headphone outputs), the Audient makes the most sense for my purposes.If I was connecting to a desktop/laptop and not the iPad Pro then the USB 2 on the other interfaces would be just fine. Still need to decide if it's worth the extra $100 ($299) to go with the iD14 vs the iD4.

Almost none of that is correct except in "Marketing Departmentland", a mysterious place where "reviews" make it up as they go along.

a) They all use the same chip family containing the mic pres and DAC (and Line I/Os and 'phone amps etc.). I'm under an NDA and cannot reveal the manufacturer but I was paid to look under the hood and write a comparison report. Reading the specs and doing a little research isn't hard. I figured it out quickly and did so before I cracked open the first unit. The 8 I/O version including 2 headphone amps cost $6.76 each (min. 1000) when I looked it up. The specs and RTL are excellent and at those prices, why would anyone use anything else in their inexpensive interfaces? A: They don't. Besides the M2/M4, I'm pretty certain that MOTU is using these in the Ultralite Mk5.

b) There are other interfaces claiming USB 3 and TB3. You can't use a Thunderbolt interface with an iPad because Apple supports TB3 for video only. The difference between "Fast USB 2" and USB 3 claimed RTL (round trip latency) is about the same as moving your ears a foot or so closer or further away from your monitor speakers when all other things are equal. You cannot hear it. Read the specs, do the math using the speed of sound at sea level. This is "Marketing Departmentland" in all its glory. Changing your buffer size has a much greater effect on RTL.

c) There is no such thing as "true phantom power operation over the USB bus". Reading that on one web site makes me ask the question: What else are they making up? Phantom power is generated by the interface and how much current draw is determined by the preamps + microphones. This is an overall power draw and the older lightening iPad Pros didn't supply as much voltage and current as the M1 iPP which should have enough for any current bus powered device. That does not mean you won't need a hub because you'll want to keep your iPad battery charged. As the old saying goes, YMMV.

The M2/M4 is also on the nosier side…

None of my tests revealed that using the same mics and line loads. Beware of "Marketing Departmentland" where tests and zeros are quoted without any references to a measurable standard.

BTW, many of the features claimed by them such as "Loopback" and "Ultra Low Latency Software Mixer" do not exist in iOS. The M2/4 has the same limitation—no Loopback either. Class Compliant only, no drivers in iOS.

Lastly, I have no dog in this fight. Everything using this chip family is excellent. Buy the features you want and ignore the nonsense from "Marketing Departmentland".

Although I have an M4, it's not the one I use day in and day out. Mine has 8 channels I/O over USB, including a pair of DIs plus 2 Line I/Os plus 2 'phone amps plus MIDI and 4 mic pres with an additional emphasis circuit that can handle my SM7b and ribbon mics. It's not bus powered but I don't need that and it works great with my lightening iPad Pro. MOTU doesn't make anything with that feature set.

[tbwnm]

Thanks for the most helpful/informative response. Yes, "Marketing Departmentland" is a place that I find myself a frequent guest! I found this review helpful (also offers some technical comparisons to the M2 and comparable interfaces).

https://youtu.be/sXDn2CPoaMQ

At 9 minutes in, this review tests USB power generation, but I don't know what material effect (if any) this will have on the iPad Pro 2021 M1 (and I can't find anyone who has actually done a comparison using this iPad Pro model). Based on the test, this review recommends "for the best headphone monitoring quality choose an audio interface with an external power supply or USB 3 connectivity".

https://youtu.be/EkwWzJa-i4M

As you mentioned, you really can't go wrong with any of these interfaces (certainly more than enough for my 14 year old daughters project studio ( which begs the questions is this really for her or me?)! Can you confirm that the M2/M4 can draw enough power from the iPad Pro 2021 USB C connection for phantom power and also drive the headphone output sufficiently without distortion at higher levels without the need for a powered USB 3 hub and finally is it compatible with Garage Band on iOS? Although more just "Marketing Departmentland" speak, the M2/M4 manual makes not mention of iOS compatibility and does not appear to have been designed with this purpose in mind.

Many thanks!

Gerard

[rezwits]

Finally, I can say this is an AMAZING BUS POWERED 4x4 Audio Interface!!

So, I just wanted to help out the MOTU M4 communities, as I finally have solved my problems with the MOTU M4.
I used a simple USB-C 3.0 cable and connected the M4 to my iPad Pro M1, results:
every 10 seconds crackle crackle, after 1 month, I couldn't take it, so then...
I used a really good TB3 cable and connected the M4 to my iPad Pro M1, results:
every 30 seconds crackle, after 6 months, I couldn't take it, so then...
I bought and used an OWC TB4/USB4 cable (0.7 meters), connected the M4 to iPad, results:
Not 1 crackle and whisper quiet! Works 100%, bus powered from iPad Pro M1.

Summary, literally less noise and crackling as you go from USB3 -> TB3 -> TB4...
Even tho it's "Data" it's still garbled...

As a side note, connecting an M4 to a MBP w/M1 using the TB3 cable was fine, unless connected right next to the MagSafe Cable, (USB3 cable, crackle crackle), and this TB4 cable from OWC deliveries 100W power so there should be no problems... I highly recommend spending $25 for the TB4 cable if you have the M1 iPad Pro (or M2 now)

Laters...

[mikehalloran]

Thanks for that. A number of users have reported similar noise issues—but the MOTU supplied cable wasn't a problem except that it wasn't long enough. The solution was a well built USB 2 cable. Many TB3 /4 cables do not support USB 2 (and state this) — glad that you found a cable that does.

uSB 2 and USB 3 are separate protocols. Many, including some cable resellers, do not understand this and believe that USB 3 is backwards compatible—it is not. A properly built cable carries wiring for both protocols with only the ground in common.

In the early days of USB 3 Macs there were a lot of problems with this and the solution was to buy a hub that had separate ports for USB 2 and 3 Out. Fortunately, that isn't an issue anymore but along comes USB-C and a lot of people are confused—and not just consumers.

USB-C is a port only and has no protocol of its own. One must read cable specs carefully nowadays and hope that the vendors understand what they are selling (or reselling). USB-C cables that support USB 2 are readily available if you need to buy another.