Professional audio/Hardware

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M-Audio Delta 1010

The M-Audio Delta series cards are based on the VIA Ice1712 audio chipset. Cards using this chip require that you install the alsa-tools package, because it contains the envy24control program. Envy24control is a hardware level mixer/controller. You can use alsa-mixer but you will save yourself some hassle not to try it. Note that this section has no information on MIDI setup or usage.

Open the mixer application: 

$ envy24control

This application can be more than a bit confusing; see envy24control for guidance on its use. That said, here is a very simple working setup for multitracking with Ardour.

  1. On the "Monitor Inputs" and "Monitor PCMs" tabs, set all monitor inputs and monitor PCMs to around 20.
  2. On the "Patchbay / Router" tab, set all to PCM out.
  3. On the "Hardware Settings" tab, verify that the Master Clock setting matches what is set in Qjackctl. If these do not match you will have xruns out of control!

M-Audio Fast Track Pro

The M-Audio Fast Track Pro is an USB 4x4 audio interface, working at 24bit/96kHz. Due to limitation of USB 1, this device requires additional setup to get access to all its features. Device works in one of two configuration:

  • Configuration 1, or "Class compliant mode" - with reduced functionality, only 16bit, 48kHz, analogue input (2 channels) and digital/analogue output (4 channels).
  • Configuration 2 - with access to all features of interface.

Currently with stock kernel it runs in configuration 2, but if you want to make sure in what mode you are, you can check kernel log for entries: 

usb-audio: Fast Track Pro switching to config #2
usb-audio: Fast Track Pro config OK

The interface also needs extra step of configuration to switch modes. It is done using option device_setup during module loading. The recommended way to setup the interface is using file in modprobe.d: 

/etc/modprobe.d/ftp.conf
options snd_usb_audio vid=0x763 pid=0x2012 device_setup=XXX index=YYY enable=1

where vid and pid are vendor and product id for M-Audio Fast Track Pro, index is desired device number and device_setup is desired device setup. Possible values for device_setup are:

device modes
device_setup value bit depth frequency analog output digital output analog input digital input IO mode
0x0 16 bit 48kHz + + + + 4x4
0x9 24 bit 48kHz + + + - 2x4
0x13 24 bit 48kHz + + - + 2x4
0x5 24 bit 96kHz * * * * 2x0 or 0x2

The 24 bit/96kHz mode is special: it provides all input/output, but you can open only one of 4 interfaces at a time. If you for example open output interface and then try to open second output or input interface, you will see error in kernel log: 

cannot submit datapipe for urb 0, error -28: not enough bandwidth

which is perfectly normal, because this is USB 1 device and cannot provide enough bandwidth to support more than single (2 channel) destination/source of that quality at a time.

Depending on the value of index it will setup two devices: hwYYY:0 and hwYYY:1, which will contain available inputs and outputs. First device is most likely to contain analog output and digital input, while second one will contain analog input and digital output. To find out which devices are linked where and if they are setup correctly, you can check /proc/asound/cardYYY/stream{0,1} . Below is list of important endpoints that will help in correctly identifying card connections (it easy to mistake analog and digital input or output connections before you get used to the device): 

EP 3 (analgoue output = TRS on back, mirrored on RCA outputs 1 and 2 on back)
EP 4 (digital output = S/PDIF output on back, mirrored on RCA outputs 3 and 4 on back)
EP 5 (analogue input = balanced TRS or XLR microphone, unbalanced TS line on front)
EP 6 (digital input = S/PDIF input on back)

This .asoundrc file enables 24-bit IO on the fast-track pro (and I'm sure it could be modified to work with other 3-byte usb devices) within the context of jack's 32-bit interface while routing default alsa traffic to jack outputs on the audio interface. Alsa will be in S24_3BE mode but jack can plug S32_LE data in and out of the interface and other alsa programs will be able to plug almost anything into jack. 

### ~/.asoundrc
### default alsa config file, for a fast-track pro configured in 24-bit mode as so:
### options snd_usb_audio device_setup=0x9
### invoke jack with: (if you use -r48000, change the rate in the plugs as well)
### $jackd -dalsa -P"hw:Pro" -C"hw:Pro,1" -r44100

## setup input and output plugs so jack can write S24_3BE data to the audio interface

pcm.maud0 {
	type hw
	card Pro
}

#jack_out plug makes sure that S32_LE data can be written to hw:Pro
pcm.jack_out{
	type plug
	format S32_LE
	channels 2
	rate 44100
	slave pcm.maud0
}

pcm.maud1 {
	type hw
	card Pro
	device 1
}
## jack_in plug makes sure that hw:Pro,1 can read S32_LE data
pcm.jack_in {
	type plug
	format S32_LE
	channels 2
	rate 44100
	slave pcm.maud1
}
#####
# route default alsa traffic through jack system io

pcm.jack {
    type jack
    playback_ports {
        0 system:playback_1
        1 system:playback_2
    }
    capture_ports {
        0 system:capture_1
        1 system:capture_2
    }
} 
pcm.amix {
	type asym
	playback.pcm "jack"
	capture.pcm "jack"
	}
pcm.!default {
	type plug
	slave.pcm amix
}

Tascam US-122

This does not apply to the US-122L

Required packages: alsa-tools alsa-firmware fxloadAUR.

Create the following rules file, then reload udev rules, Udev#Loading new rules 

/etc/udev/rules.d/51-tascam-us-122.rules
SUBSYSTEMS=="usb", ACTION=="add", ATTRS{idProduct}=="8006", ATTRS{idVendor}=="1604", RUN+="/bin/sh -c '/sbin/fxload -D %N -s /usr/share/alsa/firmware/usx2yloader/tascam_loader.ihx -I /usr/share/alsa/firmware/usx2yloader/us122fw.ihx'"
SUBSYSTEMS=="usb", ACTION=="add", ATTRS{idProduct}=="8007", ATTRS{idVendor}=="1604", RUN+="/bin/sh -c '/usr/bin/usx2yloader'"

Plug in the unit. The device should now be working, there are no software mixer controls

RME Babyface

It works very well at low latencies (~5ms) with alsa-utils, jack2 and linux-rt. Running on ALSA only with the standard kernel may cause crackling at lower latencies.

To be recognized and work, the firmware version of the Babyface needs to be >= 200, which introduces the Class Compliant Mode. To enter Class Compliant Mode hold the "Select" and "Recall" buttons while connecting the Babyface to the computer via USB. It should now be recognized.

To check if it is recognized: 

$ grep -i baby /proc/asound/cards

For more info about the Class Compliant Mode visit RME's website, they have PDF which covers all the functionality.

The Babyface does not need any special Jack Settings. But if you want to use the built in MIDI In/Out then you need to set the "MIDI Driver" to "seq" and optionally disable "Enable Alsa Sequencer Support" to use it in combination with other MIDI Devices (a USB Midi Keyboard for example).

Behringer UMC202HD/UMC204HD

Some Behringer UMC audio interfaces are known to hang up after sleep[1]. Reloading the snd_usb_audio module may resolve the issue. But usually it is enough to reset the USB device:

  1. Install usbutils.
  2. Find a device name with usbreset command, it gives 3 columns of bus numbers, IDs and product names.
  3. Run the command with an argument e.g. with a product name: usbreset 'UMC204HD 192k'.

It can be done automatically with a systemd service: 

/etc/systemd/system/reload-snd_usb_audio.service
[Unit]
Description=Restart Behringer USB audio interface connection
DefaultDependencies=no
After=sysinit.target local-fs.target suspend.target hibernate.target
Before=basic.target

[Service]
Type=oneshot
# Edit the argument
ExecStart=/usr/bin/usbreset 'UMC204HD 192k'

[Install]
WantedBy=basic.target suspend.target hibernate.target

Do a daemon-reload, then enable reload-snd_usb_audio.service.