MOTU 24AI - limited to 24x24?

[monkey man]

Yeah... but this was in MOTU's documentation... not Apple's.

Yeah, but Apple set the standard so it's likely MOTU got the info from the company.

OTOH, MOTU may have tried to run an OS native to one of the newer machines on an "incompatible" 'puter for testing, which is unlikely IMHO.

[monkey man]

What it comes down to is I don't know for-sure and of course I'm keen to hear what Mike or anyone who's conducted the testing I referred to above has to say.

[James Steele]

Yeah... but this was in MOTU's documentation... not Apple's.

Yeah, but Apple set the standard so it's likely MOTU got the info from the company.

I really have no idea where it came from. We don't really know for sure.

I think this is as good a time as any to break out this emoji:

[Funkstar De Luxe]

I’ve got a new Mac Studio arriving in a few weeks. Can test it out then

[PhireAlly]

Hi All,

One thing to note is ....
The Apple Core Audio Driver is limited to 24 in and 24 out when connected via USB.

I have seen scenarios where the MOTU AVB Audio Interface was not connecting to the MOTU Driver but rather, connecting to Apple's Core Audio Driver (which as stated in the previous sentence) was the cause of the I/O limitation.

In some situations, either an update to the OS or an uninstall and re-install of the MOTU Driver may serve as a solution.

Hope that helps
PhireAlly.

[Funkstar De Luxe]

Hi All,

One thing to note is ....
The Apple Core Audio Driver is limited to 24 in and 24 out when connected via USB.

I have seen scenarios where the MOTU AVB Audio Interface was not connecting to the MOTU Driver but rather, connecting to Apple's Core Audio Driver (which as stated in the previous sentence) was the cause of the I/O limitation.

In some situations, either an update to the OS or an uninstall and re-install of the MOTU Driver may serve as a solution.

Hope that helps
PhireAlly.

This is exactly what was happening. Thank you for clearing that up.

[PhireAlly]

Just went digging a bit more and found the info below at this link:

https://motu.com/techsupport/technotes/ ... imitations

Limitations Regarding Direct AVB Audio Connection to a Mac

While you can connect a MOTU Pro Audio interface to a computer running macOS 10.10 or later with just an ethernet cable, there are some performance drawbacks compared to connecting with USB or Thunderbolt.

Apple's current implementation of direct AVB audio streaming in macOS (first introduced in macOS 10.10) does not allow the use of third party drivers. You will not be able to use the MOTU Pro Audio driver when connecting your MOTU interface to your Mac via Ethernet for the purposes of multi-channel audio I/O. Using Apple's AVB audio driver has several limitations. These include:

1) Sample Rates of 44.1 kHz, 88.2 kHz and 176.4 kHz are not supported.
2) The MOTU Audio Tools application is not supported.
3) MIDI is not supported.
4) Increased latency between the interface and computer when compared to USB and Thunderbolt connections.
5) Audio MIDI Setup settings for the AVB device are not saved upon reboot.

What's interesting to me here is that you cannot use a sample rate LOWER than 48 kHz. You can't use 44.1. Your choices are 48, 48 or 48. Sometimes you can even do 48. Again, though, in practical terms that's not much of an issue. That's all I use now.

And yes... "increased latency... when compared to USB and Thunderbolt connections."

I have been down this road....
I've posted somewhere around here the steps I've taken to get my MOTU AVB interfaces to work with AVB via Ethernet.
This was the way I had to work before MOTU developed an Apple Silicon Driver.
It was challenging the say the least ... but it worked.

It does require some basic understanding of the AVB protocol and a few specific setup adjustments of the Core Audio AVB Driver.

In regards to latency .... The AVB protocol allows for sub 2ms "hops" between devices but the Built-In CoreAudio AVB Driver is not as optimized as MOTU's Driver.

Also true .... AVB only supports 48k and 96k sample rates. (Great if you're gonna do Dolby Atmos)

I don't recall having to change settings in the Audio MIDI Setup whenever I shut down or rebooted while I was working this way but its been awhile since so my memory could be foggy on that.

PhireAlly

[James Steele]

One interesting tidbit I picked up on another forum somewhere is that with Apple Silicon computers, you have to enable the Ethernet port to use AVB. There was someone with an issue where his Mac wasn't communicating via the Ethernet port with an AVB device and he had to go in and toggle this setting (shown below with red arrow):

It's in Settings > Network > Ethernet > Details

Just passing this along in case it's useful... not necessarily pertaining to this situation, but it's good info I wasn't aware of before.

ethernetavb.jpg (66.03 KiB) Viewed 2829 times