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diff --git a/audio/alsa-tools/tascam-us122-HOWTO b/audio/alsa-tools/tascam-us122-HOWTO new file mode 100644 index 0000000000..ea36dcfce3 --- /dev/null +++ b/audio/alsa-tools/tascam-us122-HOWTO @@ -0,0 +1,270 @@ +How to get a Tascam US-122 working with Slackware 13.37. + +The Tascam US-122 is a bus-powered USB 1.1 audio interface, with 2 +channels of input (either 1/4" unbalanced or XLR balanced) and adjustable +direct monitoring. See Tascam's product page for more information (Links +section, below). + +These directions might also be useful for the US-224 and US-428. There are +also US-122MkII and US-144MkII units which are cosmetically different, +but might be the same thing internally (or might not; I don't have one +for testing). + +Before you start: the US-122 is bus-powered, and draws quite a bit more +power than your average USB device (though not more than the 500mA that +the USB specification says USB ports/hubs should support). It probably +won't work with cheap powered USB hubs (it may be detected & show up +in alsamixer, but fail to actually play any audio). It will of course +never work with an unpowered hub. It's also possible (but unlikely) that +it could fry a cheap motherboard, if plugged in without a hub. If you're +even slightly worried about this, I'd recommend getting a decent powered +hub (one that says it supports "high power" or "hi-power" USB devices). + +You should read the owner's manual (see Links, below). Obviously you +can skip the parts about installing/using the Windows/Mac drivers and +software (which is most of the manual actually), but the product specs +in the back are informative. + +Unlike some other "USB mixer" devices, the Tascam isn't just plug and +play on Slackware Linux systems. Although it appears as a standard +class-compliant USB audio interface (and also as a MIDI interface), +it requires its firmware to be sent over the USB cable each time it's +plugged in. Presumably, this is to save on cost (no ROM or flash is +required inside the unit), and to allow for easy firmware upgrades. + +To get the device to work, you'll need the firmware itself, the firmware +loader utility, and some udev rules that cause the firmware loader to +be run when the device it plugged in. Read on for the gory details... + +To start with, leave the device unplugged. + +The commands below assume you have root access (either logged in as root, +or via "su -". Don't use "su" without the hyphen though). + +Steps +----- + +1. To get the US-122 working without audio glitches: + +# echo 'options snd_usb_usx2y nrpacks=1' > /etc/modprobe.d/tascam.conf + +What this does is reduce the number of audio packets sent in each USB +packet. Without this, the Tascam worked, but every few seconds its +audio would get "scratchy" sounding (due to dropped samples). When this +happened, I was using jack, and it didn't report any x-runs. I don't +really understand why nrpacks works, I found it by googling (see the +links section, below). + +2. Install fxload and alsa-tools from slackbuilds.org. + +# sbopkg -i fxload alsa-tools + +If you prefer, you can download the SlackBuild tarballs and build them +manually, instead of using sbopkg. + +If you're not actually using Slackware, or if you decide to compile +alsa-tools without using the slackbuilds.org package, see the "Udev Rules" +section of this document. + +3. Plug in the device. + +After a couple of seconds, the green USB light on the Tascam should light +up. The snd_usb_usx2y should be auto-loaded by udev (check the output of +"lsmod"). + +4. Testing + +Have a look at the output of "aplay -l", and/or run alsamixer and press +F6. The card should show up as "USX2Y [TASCAM US-X2Y]". It will probably +be device #1 (the numbering starts at zero, and your internal/onboard +audio normally shows up as device #0). + +Example: +# aplay -l +**** List of PLAYBACK Hardware Devices **** +card 0: Intel [HDA Intel], device 0: ALC269 Analog [ALC269 Analog] + Subdevices: 1/1 + Subdevice #0: subdevice #0 +card 1: USX2Y [TASCAM US-X2Y], device 0: US-X2Y Audio [US-X2Y Audio #0] + Subdevices: 1/1 + Subdevice #0: subdevice #0 + +Since it's card #1, we should be able to use it to play an mp3 or ogg file +with mplayer, like so: + +# mplayer -ao alsa:device=hw=1 somesong.mp3 + +You can use some other audio player, if you don't have mplayer installed. +Whatever you use, set its audio device to "hw:1" (no, the "device=hw=1" +above isn't a typo, it's how you tell mplayer to use "hw:1". Really.) + +Obviously you need speakers or headphones plugged into the Tascam, to +actually hear anything. Also, the headphone and main volumes have to be +turned up. There's no software volume control (you can't use alsamixer +or KDE's volume control), you'll have to actually turn the knobs :) + +Troubleshooting +--------------- + +If you don't hear any audio, and/or mplayer (or whatever audio playing +app) gives error messages and/or freezes up, the Tascam might not be +getting enough power. Run "dmesg|tail" and look for messages like: + +[623530.547384] Sequence Error!(hcd_frame=226 ep=10out;wait=226,frame=223). +[623530.547386] Most propably some urb of usb-frame 226 is still missing. +[623530.547387] Cause could be too long delays in usb-hcd interrupt handling. + +Try a different powered USB hub, or try it in a USB port on the PC itself. + +Once you get everything working, you should be able to use the US-122 +with jack (with or without qjackctl). Make sure to enable the MIDI ports +(-Xseq on the jackd command line) if you plan to use them. + +(Apparently, the US-428 requires a daemon called us428control to be +running, to get the MIDI controls to work. I haven't got a US-428 so I +don't know anything about this) + +JACK Latency +------------ + +As a USB 1.x device, the Tascam's audio latency is going to be pretty +awful. To measure it, you loop the output back into the input, and run +jack_delay (I used a 1/4" guitar cable, connected from the headphone +output to the left line input jack). Make sure the "Direct Monitoring" +switch is off, or else it will feed back and jack_delay won't be able +to measure anything. + +I've measured my Tascam with jack_delay. Results: + +# jack_delay -I system:capture_1 -O system:playback_1 -E + 210.625 frames 4.388 ms + +To get jack-using applications to compensate for latency, use the -I and +-O options. jack_delay's README says: + + To determine the correct values for jack's -I and -O, set both + of them to zero ('default' in qjackctl) and measure the latency + using the -E option. Then set each of the -I and -O options to + half the value displayed. + +The options can't be fractional, so I use "-I 105 -O 105", which seems +to work OK. My complete jackd command line looks like: + +/usr/bin/jackd -Z -R -P65 -dalsa -dhw:1 -r48000 -p256 -n3 -Xseq -I105 -O105 + +With these settings, I'm able to use fluidsynth, beatrix, bristol, +and other audio synths. I use a USB MIDI keyboard, but you could +use the Tascam's MIDI in jack with a standard MIDI keyboard as well. +ardour and ecasound also work for recording audio, though I haven't +tested them thoroughly. + +I haven't experimented with the -p and -n options. Lower values would +mean less latency, at the expense of more CPU and I/O overhead. I'm using +the Tascam with an eeePC (relatively slow single core Intel Atom CPU), +you might do better on faster hardware... but don't expect miracles: +USB 1.1 just plain doesn't move data fast enough to get truly low latency +audio. You'd need USB 2.0 (expensive, proprietary) or better yet, Firewire +(also expensive) for that. + +If you can't seem to get rid of audio problems any other way, try +(in order): + +- make sure jackd and your audio applications have the appropriate + POSIX capabilities (e.g. setcap cap_ipc_lock,cap_sys_nice=ep + /usr/bin/jackd) + +- add append="threadirqs" in lilo.conf (re-run lilo, reboot) + +- use the rtirq script from http://www.rncbc.org/jack/ + +- recompile the kernel with CONFIG_PREEMPT=y + +- Use a realtime-patched kernel + from http://www.kernel.org/pub/linux/kernel/projects/rt/ + +There is a lot of info out there on the 'net about reducing latency +and/or x-runs in jack. You'll get it working if you're persistent. + +Miscellaneous +------------- + +This isn't Slackware- or Linux-specific information, but it's not covered +real well in the owner's manual either. + +Unlike some other "USB mixer" devices, the Tascam won't work as a +standalone mixer. It's USB-powered, and needs its firmware loaded. + +The Direct switch sends whatever's coming in on the inputs, directly to +the output, with no latency. In ardour, select "Options > Hardware does +monitoring" to use this. If you want to use the Tascam + your computer +as a live guitar effects rig (maybe using rakarrack, jack-rack, and/or +sooperlooper), this needs to be disabled. + +The inputs are labelled L and R (left and right). When the Mono switch +is in the On position, both channels are mixed together and appear on +the left and right outputs (and on both system:capture_* ports in jack). +The device still appears to be stereo from jack and alsa's point of view +(just with identical audio on both channels). + +The insert jacks are described as "TRS jacks" in the manual. This means +tip-ring-sleeve. Probably you'll need a stereo 1/4" Y-cable (with two +mono 1/4" plugs or jacks on the other end) to make any use of the inserts. +I haven't tried them yet. See http://en.wikipedia.org/wiki/TRS_connector + +There are no software-controllable mixer controls. You can only adjust +the volume with the hardware knobs (separate ones for headphone and +line outputs). + +You can't use the US-122's controls as a MIDI control surface. From what +I've read, the US-428 is capable of this. + +Links +----- + +Tascam US-122 product page: http://tascam.com/product/us-122/ +The owner's manual is in the "Downloads" section. + +These instructions were adapted from the Fedora Core 5 instructions here: +http://www.astro.caltech.edu/~mcs/tascam_us122/ + +Ubuntu forum topic about Tascam devices (there's a lot of noise, but some +useful info too): +http://ubuntuforums.org/showthread.php?t=30891 + +The US-122L, US-122MkII, and US-144 are apparently completely different +beasts. Here are a couple of pages discussing them (which may contain +outdated information, YMMV): +http://www.premiumorange.com/la-page-web-of-phil/index.php?page=P030001 +http://mailman.alsa-project.org/pipermail/alsa-devel/2011-November/045912.html + +Udev Rules +---------- + +If you used the slackbuilds.org package of alsa-tools, you don't need +this (it already includes a suitable set of udev rules for the US-122, +US-224, and US-428). + +# cat > /lib/udev/rules.d/99-tascam.rules <<EOF +BUS=="usb", ACTION=="add", SYSFS{idProduct}=="8006", SYSFS{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'" +BUS=="usb", ACTION=="add", SYSFS{idProduct}=="8007", SYSFS{idVendor}=="1604", RUN+="/bin/sh -c '/usr/bin/usx2yloader'" +EOF + +(the above is two long lines beginning with "BUS==". There shouldn't be any +other line breaks) + +For the US-224, change the "us122fw.ihx" above to "us224fw.ihx", and +change the SYSFS{idProduct} numbers to 8004 and 8005. For the US-428, +the firmware is "us428fw.ihx" and the product IDs are 8000 and 8001. + +After creating the udev rules file, tell udevd to load it: + +# udevadm control --reload-rules + +Author +------ + +B. Watson (yalhcru at gmail dot com) + +If you find anything confusing or inaccurate in this guide, or have more +information (particularly about the other Tascam US-series interfaces), +let me know and I'll update the guide at some point. |