This app note is a short example of recording multichannel audio on Linux using miniDSP devices.
Please note: miniDSP can't provide support for non-miniDSP hardware and software. In particular, we cannot trouble-shoot Linux-related issues. If you get stuck with Linux and miniDSP hardware, try a simple configuration such as the one we describe here and then proceed from there.
What you will need [Top]
For multichannel recording, you will need one of the following USB interfaces:
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The USBStreamer (or kit version) supports 8-channel ADAT and 8-channel PCM over I2S (with an additional two channels via TOSLINK).
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The MCHStreamer supports many different formats, including 8-channel ADAT and 8-channel PCM over I2S (optionally with an additional two channels via TOSLINK or SPDIF), PDM and TDM.
- The USB microphone array series (UMA-8/UMA-8SP/UMA-16) support multichannel audio for custom beamforming algorithm development
- The U-DIO8 supports 8 channels of input and output via AES/EBU or SPDIF (BNC).
These devices are all USB Audio class-compliant, so will work on Linux without any driver installation required.
In the case of the MCHStreamer and USBStreamer, the correct firmware must be loaded to configure it for the desired I/O format. For example, for ADAT I/O, load the ADAT firmware. See the relevant user manual for the procedure.
Linux setup and DAW installation [Top]
As a concrete example for this app note, we installed Linux Mint, a user-friendly distribution of Linux, on an Intel NUC. Because of the wide variety of Linux systems, you may need to do things a bit differently depending on the Linux distribution you have installed on your own computer.
For multichannel recording, you will also need a DAW (Digital Audio Workstation) application. For this app note, we installed Ardour. Once the installer is downloaded, open and install it. In Mint, for example, double-click on the downloaded file and then click on the Install Package button.
During the installation process, there were a number of options:
- We elected to install Jack (although we didn't use it for this app note).
- We chose to enable realtime scheduling:
Create a project [Top]
First make sure that your miniDSP device is connected to your Linux computer via USB. In the case of the U-DIO8, power it on.
To start Ardour, locate it in the main menu in the Sound & Video section. (Your version of Linux may be different.) When Ardour starts, set the parameters as shown here:
Note that the miniDSP MCHStreamer is automatically detected and can be selected from the dropdown menus for the Input and Output devices.
On the next screen, enter 8 for "Create Tracks," then click OK:
Record audio [Top]
Enable all tracks for recording. This screenshot shows the record enable button for one track:
Then press the main record and play buttons, in that order:
Ardour will record all 8 input channels from the MCHStreamer, USBStreamer, or U-DIO8. Here's our screen after recording an 8-channel file over ADAT with an MCHStreamer:
You can now proceed to mixdown or export to a file. Have fun, and please let us know how you go in our forum!
Related Products - USB Audio products
