Mac, Audiofire 12, Ableton Input crackles.....

[orphee]

Utter hearsay, but I was told by someone at some point that in general the buffer size likes base 2 numbers e.g. 64, 128, 256, 512, etc. I have no scientific evidence or knowledge that there is anything to this theory, but I always use them - just in case...

FWIW I run 128 on my two AF12's at 24/48 with very little issues - I never change the buffer setting. I do change to 16/44.1 on occasion when collaborating with other folks who use that setting, and I've never had a problem.

One final thought - I'm still running 10.5.8, I wonder if 10.5 has a more stable implementation of the aggregate device system than 10.6+?

I'm a computer systems engineer, no it's not heresay that computers prefer powers of 2, but it depends on the way the software is programmed. The computer software can be more efficient if you use x^2, but only if the software was designed that way. I don't believe Ableton's audio buffers are designed this way.

Can I ask - what Mac hardware are you running? I'm running an iMac 2011 27", but I'm curious what you're having success on, because I've never got anywhere near 128 samples buffer with 2x AudioFire12s! One thing I haven't tried is driving the whole system from my MacBook Pro.

Thanks for the detailed system info! I haven't tried OS X 10.5, however I've had serious problems with aggregate audio in 10.6.x... In earlier versions of 10.6 the computer wouldn't start with aggregate devices, and Audio MIDI prefs wouldn't open and would hang the whole system (not kernel panic, just hang the entire computer). The only fix was to delete the aggregate device with the audio interfaces disconnected.

I don't have any concrete evidence, but I also suspect there is a problem with aggregate devices.

Can I please also ask what AudioFire12 driver version you're using?

Thank you!
orph

[southsounder]

I certainly don't pretend to even come close to understanding the intricacies surrounding host program and device driver interaction. I'm a bass player, this stuff is all voodoo to me!

I've been using the base 2 settings out of habit for a long time and have never really had problems - except with the aforementioned Presonus Universal Control, which had issues no matter what setting I tried. My friends who have switched to using base 2 buffer settings have reported better stability on FW systems as well. Again - not a scientific or controlled study by any means.

I'm running a circa 2009 Mac Pro, the typical 2x 2.8quad version, with 8gig RAM and OSX 10.5.8. I've got Echo console version 5.3, and ARM and DSP firmware 4.8. My usual settings are 24/48 which at 128 samples gives me just over 11 sec total latency.

[orphee]

I certainly don't pretend to even come close to understanding the intricacies surrounding host program and device driver interaction. I'm a bass player, this stuff is all voodoo to me!

That's alright I'm a drummer. We should make a good pair!

I've been using the base 2 settings out of habit for a long time and have never really had problems - except with the aforementioned Presonus Universal Control, which had issues no matter what setting I tried. My friends who have switched to using base 2 buffer settings have reported better stability on FW systems as well. Again - not a scientific or controlled study by any means.

I'm running a circa 2009 Mac Pro, the typical 2x 2.8quad version, with 8gig RAM and OSX 10.5.8. I've got Echo console version 5.3, and ARM and DSP firmware 4.8. My usual settings are 24/48 which at 128 samples gives me just over 11 sec total latency.

Cool! Thanks for answering, that's good to know. I tried 128 samples after you said and it worked solidly for a few hours! Then it all broke up and everything went to hell on any latency :-/. Something else is going on here, and it's crap. I'm wondering if it's something to do with the iMac firewire or OS X 10.6. I wonder if 10.5 would work better.

Seriously I'm over this. I had 2x Profire2626's before this, and they broke up too. I'm seriously considering a Windows box and getting off of OS X.. I would have already only my UAD2 Satellite doesn't work with Windows..

Thanks again for your help!
orph

[analogcabin]

Just an update on my situation.

So I tried each driver (and flashed the AF12 firmware. It really helped when I uninstalled the old driver and deleted the pref. file & .plist file etc.
I rolled back my Echo driver to 4.8 and all things are far more smooth. 512 sample buffer (at 80% CPU) but I monitor pre-DAW anyhow.

For a lark I bought a used Presonus Firestudio Project. Installed the latest driver and wow...... it is far cleaner buffer wise. Easily getting 64 sample buffer at 80% CPU and 32 at 60% CPU.

This is a mind blow. Both units are using a core audio driver so this is odd I think.

Running OSX 10.7.5. - Live 8.3.4

[orphee]

For a lark I bought a used Presonus Firestudio Project. Installed the latest driver and wow...... it is far cleaner buffer wise. Easily getting 64 sample buffer at 80% CPU and 32 at 60% CPU.

Right...! That doesn't bode well. Can I ask do you use the aggregate audio driver with the AF12 at all?

I get a lot more stable audio with 1x AF12 and not using the aggregate audio. I still think that's where the problem is...

This makes me sad man.. All I want is 24in/24out audio that's fast and stable and clear (and that i don't have to run lightpipes all over the place)

[analogcabin]

Hi
No I only run a single AF12. There is something goofy going on with the Echo unit or driver. They (in theory) are just using the Core Audio driver spec but there must be more to the equation.
Presonus makes solid stuff but I've never heard anyone brag about their drivers. But this Firestudio Project locks in thight.
The Audiofire and my (M80) pre's sound smoother though.

Not done yet