Core Audio - Ravenna

[Mike Hatch]

Hi all, I have a question regarding accessing the Ravenna network via core audio on a Mac.

Currently the Core Audio driver seems to be limited to 64 channels. Does anyone know why this is and will it be extended in the future? A normal Horus (without extra cards) can handle 88 inputs, and more when additional cards are added. I can't understand why the Core Audio interface is currently unable to receive all these inputs....

Anyone know more?

Mike Hatch

[Ricardo Ryan]

Hi Mike,

For now we've limited our Core Audio to 64 IO by design and because some Mac cannot achieve more then than (glitches at certain sampling rates). We could consider more IO in a near future, but you must be aware that the more IO are enabled the more performance is taken, recent Mac will sustain this better.
At which sampling rate do you work?


Best Regards,
Ricardo Ryan
QA & Project Manager
Merging Technologies

[mpdonahue]

I think what Mike is starting to get at is that the limitation is purely arbitrary and designed to move folks into Masscore systems.
I realize that this driver is free and we get far more than we pay for with it. However, I feel that the same way you could purchase an unlimited IO (Alright 128 channel) for Native back in the pre-ravenna days, you should be able to do the same today.
Clearly folks like Mike and myself are capable of determining if our systems are capable of handling the increased channel count and understand network configurations and limitations.
Seems like a no brainer and would open your products to a large group of Protools/Nuendo professional users.
I have the sneaking suspicion that the vast majority of these users are PCM only users and would gladly pay a reasonable price to have more IO.
As always, YMMV.
All the best,
-mark

[Mike Hatch]

Hi Ricardo

What I am saying is that if you have a system that can handle the data rate then you should not come up against an arbitrary limitation in the software. As it happens I need to record 64T at 192k and this actually works with your driver. So given that my system can handle this data rate why won't the software let me do 96 channels at 96k which is actually a LOWER data throughput? Look at the speeds of SSD in Raid configuration - plenty of headroom there!

Mike Hatch

[Mike Hatch]

..and I should add that this is my BACKUP system. I do use Masscore systems as the main recorder and am very happy with them, but in a multi-format world we are all looking for maximum flexibly and connectivity...!

Mike H

[mpdonahue]

Hi Ricardo
What I am saying is that if you have a system that can handle the data rate then you should not come up against an arbitrary limitation in the software. As it happens I need to record 64T at 192k and this actually works with your driver. So given that my system can handle this data rate why won't the software let me do 96 channels at 96k which is actually a LOWER data throughput? Look at the speeds of SSD in Raid configuration - plenty of headroom there!
Mike Hatch

Mike,
The other thing to remember here is that you get a bonus with the Core Audio driver. On the Windows side you lose half your channel count with each bump in sample rate (64 at 1fs, 32 at 2fs and 16 at 4fs...)
BTW, What software are you recording on? I've tested Boom Recorder on my MacBook Pro 2013 and it works fine at 64 channels/192k to a single 7200rpm drive in a thunderbolt drop-in.

Ricardo,
I know several people that are holding off on Horus/Hapi upgrades specifically due to this limitation. For those of us who own the extended native keys, it would be a nice gesture to get this functionality returned to the system for Ravenna ASIO as well.
All the best,
-mark

[Mike Hatch]

HI Mark

I use either Boom Recorder Pro or Reaper as the backup system. You can get a 4 slot hot swappable SSD raid to Thunderbolt from Blackmagic design at a really reasonable price and the write speed to that is fantastic!

Mike H

[Perfect Record]

Huub (frequently on this list) recently wrote about writing 100+ tracks to Reaper. I don't know any of the details.

I'm currently looking at Reaper as a cost effective backup recorder.

[DJS]

Yes, this is my plan. When the redundant eth port becomes available on Horus, an i5 NUC running Reaper will be plugged into it down at the stage. Enabling its remote desktop is the next challenge.