A bunch of interfaces

itsbenagain

itsbenagain

New member
I have a problem...I went a little crazy and got way too many things daisy-chained via USB (midi controlers, interfaces, hard drives) in my studio, including four focusrite 18i20s hoping to be able to get all 32 channels out of them. but I know it was wishful thinking since my 13-inch MacBook running logic won't be able to handle all the data, at least without massacring the sample rate. Online i can only find help with linking 2 via adat, but nothing about about linking 3 or 4 separate 8-channel interfaces. Given that I have I need at least 3 of the 18i20s for my current studio template (preferably all four and perhaps even more - i have a couple 2i4s connected to RCA switches and would love to be able to expand even more to accept individual channels from my analog board), what would be the cheapest way to make it work?? I really don't want to drop 2k on 32-channel live box with no manual gain adjustment, and I really feel attached to the setup I currently have with two of the 18i20s in the control room and 2 in the tracking room. Is there any way to consolidate the usb signal from the four interfaces and then bring it into the computer? If I I find a suitable slave computer could I use Vienna ensemble pro to spread the cpu load, and solve the issue that way?
 
I've never got even two interfaces working simultaneously on my macs, and never on a PC - they're just not designed to do what you are doing. My mac is happy recording from the Midas desk with it's 32 inputs, and the similar X32 Behringer. I've never known anyone even try running 4 interfaces - especially the same models. I can't think how your mac and the DAW will access this. I'm a Cubase user and when I have multiple audio devices on the system, Cubase wants me to select 1 of them - no option for two at all?

Not being funny, but why did you go down this route? It's a unique idea. My understanding of USB also suggests that if you did find a way to access multiple interfaces, timing would be dreadful as USB connections involve lots of sequencial reading and writing and buffers. Did somebody tell you it would work? The ADAT linking might work, but you'd need some kind of extra gizmo to combine them? At best, you could use interfaces with two ADAT ins, so the number of inputs on the intercface plus 16 extra channels from, two interfaces in ADAT mode. I don't know of any interfaces with 3 or more ADAT ins. So your computer would talk to the 18i20, then have two others connected via ADAT. It's a real bodge though.
 
Have you tried creating an aggregate device of your interfaces in Audio/Midi setup?
That's what it's for - The aggregate contains as many I/O devices as you want, and the recording software sees the aggregate as a single device with all that IO.

If it's possible to have two of the interfaces connected to the mac, and part of an aggregate device, then two others fed in to the first two via Adat, that would give you your 32 channels seen as one device.

Whether or not your model of mac can handle 32 channels of simultaneous IO is another question but that's the way to find out.
 
As the Dubliner said to the American looking for the airport "If I was you sor, I wouldn't have started from here."

There is a reason why multi-channel mixers and other such computer systems have been developed! I used to read reviews of top end Firewire interfaces that had two 1364 ports so that other interfaces could be daisy-chained...never read of anyone doing it tho'but!

Sell the lot and start again with RME. Oh! Forgot, Dante?

Dave.
 
I would assume you can do it by running one of the interfaces as a master, and the others as 'slaves' via the optical connections. Seems you would be better off having all of the interfaces in control room and run snake to tracking room.

That is what I do with 2 Steinberg UR824's and a Behri Pro 8. That gives me 24 simultaneous input channels.

How to do that with your Focusrites you will have to look up.

You could call Sweetwater support. I bet they would be very helpful.
 
itsbenagain said:
I have a problem...I went a little crazy and got way too many things daisy-chained via USB (midi controlers, interfaces, hard drives) in my studio, including four focusrite 18i20s hoping to be able to get all 32 channels out of them. but I know it was wishful thinking since my 13-inch MacBook running logic won't be able to handle all the data, at least without massacring the sample rate. Online i can only find help with linking 2 via adat, but nothing about about linking 3 or 4 separate 8-channel interfaces. Given that I have I need at least 3 of the 18i20s for my current studio template (preferably all four and perhaps even more - i have a couple 2i4s connected to RCA switches and would love to be able to expand even more to accept individual channels from my analog board), what would be the cheapest way to make it work?? I really don't want to drop 2k on 32-channel live box with no manual gain adjustment, and I really feel attached to the setup I currently have with two of the 18i20s in the control room and 2 in the tracking room. Is there any way to consolidate the usb signal from the four interfaces and then bring it into the computer? If I I find a suitable slave computer could I use Vienna ensemble pro to spread the cpu load, and solve the issue that way?
Click to expand...
On a Mac you can - Aggregate devices - You can combine all 4 units in this way - then Name it so the Mac will see it as one device with 32 inputs that is an Aggregate of your 4 units - - all checked the 'Drift' box to keep them in sync - the only problem I think you have is getting a USB from the the Devices to the Control room -
 
My mac is happy with 32 ins and outs - but I've never got more than two audio devices to agregate properly? Must be something I'm doing. (or not doing)
 
If you run with two interfaces connected via USB and two via adat then you get your 32 channels and you can do a lightpipe run to the next room, rather than USB.
 
That's a neat idea - I'd love to hear how it works out as that solution makes a lot of sense.

Edit - I just tried 3 different interfaces on the imac and it actually worked seamlessly. I tried recording a click and then playing them back to see if they locked together. The oldest one seemed to drift a tiny bit (an elderly lexicon omega) but I could live with it.
 
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I think if you make sure all devices are at the same sample rate (outside of the aggregate),
then also add the built in I/O to the aggregate and use it as your clock source for all, there'll be no drift or issues. (y)
 
rob aylestone said:
I've never got even two interfaces working simultaneously on my macs, and never on a PC - they're just not designed to do what you are doing. My mac is happy recording from the Midas desk with it's 32 inputs, and the similar X32 Behringer. I've never known anyone even try running 4 interfaces - especially the same models. I can't think how your mac and the DAW will access this. I'm a Cubase user and when I have multiple audio devices on the system, Cubase wants me to select 1 of them - no option for two at all?

Not being funny, but why did you go down this route? It's a unique idea. My understanding of USB also suggests that if you did find a way to access multiple interfaces, timing would be dreadful as USB connections involve lots of sequencial reading and writing and buffers. Did somebody tell you it would work? The ADAT linking might work, but you'd need some kind of extra gizmo to combine them? At best, you could use interfaces with two ADAT ins, so the number of inputs on the intercface plus 16 extra channels from, two interfaces in ADAT mode. I don't know of any interfaces with 3 or more ADAT ins. So your computer would talk to the 18i20, then have two others connected via ADAT. It's a real bodge though.
Click to expand...
Just to be clear I have them under one aggregate device already and I bought adat cables to make it into two pairs if necessary...have been able to record all 32 inputs simultaneously with the aggregate and seems to work but not been able to sound check all channels at once with full band and can't tell what's going on with sample rate or sound quality, or whether it will crash if i attempt a full session using all bells and whistles. Reason I have 4 is because I was using 2 originally, worked well for a whil but I upgraded to the newer versions (aka bought two more), and now I'm trying to see if I can incorporate all 4 into the setup
 
Papanate said:
On a Mac you can - Aggregate devices - You can combine all 4 units in this way - then Name it so the Mac will see it as one device with 32 inputs that is an Aggregate of your 4 units - - all checked the 'Drift' box to keep them in sync - the only problem I think you have is getting a USB from the the Devices to the Control room -
Click to expand...
That's actually how I currently have it going, but I kept reading that the sample rate halves for each additional unit. Do you know if this is true with aggregate devices?
 
Also thanks to everyone for replies thus far. I currently have been able to hit record button for all 32 inputs but am worried enough about sample rate and other issues to not want to have a band hire me for their recording, hence this post
 
Oh, ok. If you've already got an aggregate of two then just add in your new interfaces via lightpipe.
That really should be problem solved, as far as I know.

No, sample rate doesn't halve, or change, because you've added more devices.
You can look at your Aggregate Device settings in Audio/Midi setup in MacOS, and it will show you the sample rate there.
 
itsbenagain said:
Also thanks to everyone for replies thus far. I currently have been able to hit record button for all 32 inputs but am worried enough about sample rate and other issues to not want to have a band hire me for their recording, hence this post
Click to expand...
Gotcha.
To be honest it should like you're good. Sample rate is a non issue - Maybe a misunderstanding or bad info.
Ultimately you won't know until you do a dress rehearsal.
Maybe someone can correct me but I think recording 32 channels without actual input would be just as data intense as recording 32 sources, no?
I suppose fire up a 32 track session, hit record on everything, and see if it'll happily run for X minutes.
 
Steenamaroo said:
Oh, ok. If you've already got an aggregate of two then just add in your new interfaces via lightpipe.
That really should be problem solved, as far as I know.

No, sample rate doesn't halve, or change, because you've added more devices.
You can look at your Aggregate Device settings in Audio/Midi setup in MacOS, and it will show you the sample rate there.
Click to expand...
Thanks for your help. The halving had to do with adat only I guess. I currently have the four coming in through their own separate usb connection and am able to create an aggregate device easily. Is doing it via 4 USB cables a problem?
 
Steenamaroo said:
Gotcha.
To be honest it should like you're good. Sample rate is a non issue - Maybe a misunderstanding or bad info.
Ultimately you won't know until you do a dress rehearsal.
Maybe someone can correct me but I think recording 32 channels without actual input would be just as data intense as recording 32 sources, no?
I suppose fire up a 32 track session, hit record on everything, and see if it'll happily run for X minutes.
Click to expand...
It seems to work when I test it that way but haven't had a chance to really put it to the full test with a full band...and hear how it sounds and see if I can run chrome or plugins or whatever. But so far so good
Thanks for the info!
 
Oh, I think maybe I know what you've read - When using adat you can generally have 8 channels of input at 44.1/48.
If you switch to 88/96 you can only have four channels.

If you record at 44.1 or 48 it shouldn't be a problem.

If it is a problem, because you record at higher rates, go to plan B and just connect all the interfaces directly via USB, where adat limitations don't come into play.
Don't want to open a can of worms but most people have no real need to be recording over 48k anyway.

Edit - You got there before me. (y)
 
Steenamaroo said:
Oh, I think maybe I know what you've read - When using adat you can generally have 8 channels of input at 44.1/48.
If you switch to 88/96 you can only have four channels.

If you record at 44.1 or 48 it shouldn't be a problem.

If it is a problem, because you record at higher rates, go to plan B and just connect all the interfaces directly via USB, where adat limitations don't come into play.
Don't want to open a can of worms but most people have no real need to be recording over 48k anyway.

Edit - You got there before me. (y)
Click to expand...
Oh wow, so I had everything right already lol?
I guess I was just paranoid because the internet doesn't seem to have any reference to what I'm doing, and the adat halving sorta scared me. As long as I'm good, I'm happy
Thanks to you, and everyone else who contributed to this thread, for your help.
If anyone still sees something wrong with having 4 18i20s coming in via separate USB into an aggregate device please let me know!
 
I don't know how well multiple Focusrite drivers work but I do know that RME devices are intended to be used in multiples. For example, you can use up to 3 Digiface USB interfaces on one machine to give up to 96 inputs and 102 output channels.
 
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