Multiple Input Devices?

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User offline. Last seen 8 years 32 weeks ago. Offline
Joined: 2007-04-17

Maybe Ardour does this already I'm on my windows machine and haven't had a chance to play with it yet. But with the advent of XRL to USB conversion cables such as those from it would be great if I could connect say 6 or 8 of those bad boys and then record from each Mic to a separate audio track all at once.

The USB cables connect to any standard XRL mic, your SM57's ect. But every cable you plug in is detected as a separate audio device (at least in windows) so I need a program that can record from multilple audio devices simultaneously!

This way I could record a drum set with an individual audio track for each individual drum. Thus if the kick drum is too quiet in the recording I can simply increase the volume of the kick drum track! Or if I want to add a reverb effect to one of the tracks I can!

I have a linux box so I will eventually get around to downloading and playing around with ardour but so far no studio software I've found does what I'm describing. Does Ardour? Could Ardour?


User offline. Last seen 6 years 43 weeks ago. Offline
Joined: 2007-01-05

I think JACK will detect any working sound card in ALSA. You can connect whatever you want to the input in ardour, as long as jack recognises it.

User offline. Last seen 2 years 47 weeks ago. Offline
Joined: 2007-03-04

Ardour doesn't handle the communication with the sound device(s). JACK does it for it. So the right question is: Does JACK support multiple soundcards. And yes, it does. It is possible to stack multiple devices like your XLR to USB Mic together. The problem is, that this devices are not hardware synchronized. So it is possible that your seperated tracks are running apart after a while.

Seb's picture
User offline. Last seen 9 hours 4 min ago. Offline
Joined: 2006-04-07

Multiple Sound cards (each of those USB cables is a kind of sound card) are a bad idea because they have seperate clocks and they will eventually diverge in time as the recording goes on. Yes, ALSA supports more than one sound card at a time but jack only hooks up to one of them as far as I know. Someone I read about on the net somewhere actually managed to run multiple (identical) SoundBlaster cards in sync by soldering their quarz clocks together but that's only recommended for those who "Know What They Are Doing (R)".

Any sound card on the alsa sound card matrix (see can be used with jack and hence with ardour, and there are plenty with multiple channels. Some have XLR preamps build-in. The "XLR to USB" cable I did not find on the sound card matrix, but maybe it uses a sound chip that is supported for another device. I don't think hanging a microphone straight onto the USB is the best idea ever from a "noise" point of view, either. "Bad Boys" indeed.

User offline. Last seen 6 years 11 weeks ago. Offline
Joined: 2006-03-30

You can setup ALSA to combine multiple devices into a virtual device, and then connect to the virtual device via Jack.

However, as mentioned previously, their clocks will drift since they do not have a common clock source. This problem can be avioded if your devices can be connected to an external word-clock, but that is something that is only found on professional audio devices.

If your devices have digital IO, you _might_ be able to sync them by connecting them to each other using the digital IO ports. Digital protocols have a clock embeded into them that can be used to sync them up.