Carbon and Mac Pro 5,1 compatibility

[martthie_08]

that'd be super nice!
I am afraid that that model will not run Catalina though, without trickery... but thanks anyways!!

[dominicperry]

Originally Posted by martthie_08

that'd be super nice!
I am afraid that that model will not run Catalina though, without trickery... but thanks anyways!!

I tried just conecting the Carbon to the 2011 MBA, using a TB to Ethernet dongle, and MacOS sees the Carbon but it shows as having no ins and no outs. So, AVB is there - listed in the network browser of Audio Midi Setup - and I can see the Carbon firmware version, but even though it shows as two devices, as it should, (one for PT one for general use), both show up as 0 ins and 0 outs and it therefore can't be selected for use. I didn't load PT, as the version which works with Carbon won't (I don't think), work with High Sierra.

So, that doesn't help!!

[martthie_08]

ok, interesting, thanks for giving it a shot though!
I will at some point get a new macbook but really want to wait till end of the year for the 14" models to come out. Will need to do some location tracking in September, therefore me asking..

[dominicperry]

Originally Posted by martthie_08

ok, interesting, thanks for giving it a shot though!
I will at some point get a new macbook but really want to wait till end of the year for the 14" models to come out. Will need to do some location tracking in September, therefore me asking..

I'll try with my 2015 MBP which has Catalina and PT on it - but I suspect that has quite a bit more power than your older Air, so it may not really tell you much - I guess if it doesn't work (or the fans go nuts) then it rules your MBA out..

[dominicperry]

Originally Posted by martthie_08

ok, interesting, thanks for giving it a shot though!
I will at some point get a new macbook but really want to wait till end of the year for the 14" models to come out. Will need to do some location tracking in September, therefore me asking..

I tried the MBP 2015 with Carbon.
Machine is i7, 16GB RAM, no external monitor. I have Turbo Boost Switcher installed and have Turbo Boost off - so the CPU is permanently throttled to 2.5 GHz.
I ran the demo song - Kelly Malone, Earth and Stars, which is about 45 tracks at 44.1K, and recorded 16 tracks on the Carbon at the same time, buffer at 256 (no need - it could have been 1024, I just didn't check first). I was using 2021.3.1 as that's what's installed. Catalina 10.15.7

Machine was happy right until I deleted some big applications while it was running and caused a PT error. Don't do that!!
According to iStat menus CPU was 35% Memory was 49% so you just squeak in under 8GB. PT itself was only using ~1.5GB.
PT system usage meter was low - 15% and disk meter hardly flickering.
Carbon had an instance of Avid Channel Strip on each channel and was running in DSP mode on all 16 input channels (8 analog, 8 digital).
Mac fans ramped up from the base level of 2000rpm (silent) to about 3500 (audible but not terrible) - [maximum is 6000 which is very annoying].

Does that help - I don't know. My laptop is generally too noisy to use with PT on a heavy session, and Logic too.

Dominic

[martthie_08]

Wow Dominic, thank you so much for your testing, those are good results and it sounds rather assuring!

I wonder if the fan noise is directly related to the dsp usage on the DSP..

[dominicperry]

Originally Posted by martthie_08

Wow Dominic, thank you so much for your testing, those are good results and it sounds rather assuring!

I wonder if the fan noise is directly related to the dsp usage on the DSP..

Very happy to help.

The fan noise is directly related to the effort it takes to get the Pro Tools plates spinning and some extra for having AVB working - nothing to do with DSP on the Carbon. If I run the same song through another interface I get about 28% CPU usage. The extra 7% (taking it to 35% as stated earlier) is just from having the Carbon connected - AVB is bad for putting stress on the CPU - but it's a one-hit thing. It doesn't matter whether PT is running or not - or indeed whether you are playing any audio or not. It's just the overhead of AVB - as I've mentioned before, my Mac Pro 7.1 16-core steps up from 90watt consumption to 140watts just by connecting the Carbon, even though the CPU is in no way taxed.
The Carbon DSP is neither here nor there - unless you choose to offload some plugin processing from the session onto the Carbon, in which case the CPU load would go down a bit. But not by much quite frankly. 45 tracks (including some VIs and quite a few effects) is just too much for an old 2015 MBP to do without heating up the CPU a bit and getting a bit of fan noise.

[LukeHoward]

Originally Posted by dominicperry

... AVB is bad for putting stress on the CPU - but it's a one-hit thing. It doesn't matter whether PT is running or not - or indeed whether you are playing any audio or not. It's just the overhead of AVB - as I've mentioned before, my Mac Pro 7.1 16-core steps up from 90watt consumption to 140watts just by connecting the Carbon, even though the CPU is in no way taxed..

This seems to have been an issue with AVB on macOS right since I first tried using it with my S3 several years ago. I wonder if it is an architectural limitation of the way the networking stack works. I originally thought it might be due to the high packet frequency of AVB (8000pps for class A), but this is the same as high speed USB as I understand it. I'd have thought Apple would have sorted this by now.

[martthie_08]

Originally Posted by dominicperry

The fan noise is directly related to the effort it takes to get the Pro Tools plates spinning and some extra for having AVB working - nothing to do with DSP on the Carbon.

gotcha, thanks for the clarification.
I misunderstood and thought you were talking about the fan on the Carbon spinning up and making noise, but you were describing the fan on the Macbook.

[dominicperry]

Originally Posted by LukeHoward

This seems to have been an issue with AVB on macOS right since I first tried using it with my S3 several years ago. I wonder if it is an architectural limitation of the way the networking stack works. I originally thought it might be due to the high packet frequency of AVB (8000pps for class A), but this is the same as high speed USB as I understand it. I'd have thought Apple would have sorted this by now.

It is informative that RME have written their own AVB driver - presumably because the Apple one has some shortcomings.

There's very little information out there about AVB implementations, compared with USB or Thunderbolt. So we just have to trust that Avid and Apple will sort it out between them.