The Raspberry Pi’s hardware and software support has come a long way in the few months it has been in the wild. I first tried this application in the summer, and the results were dismal. Now, thanks much improved USB driver support under Raspbian, I’m pleased to say it works flawlessly.<\/p>\n
Earlier this year, I bought a turntable<\/a> (ack!) for transferring vinyl to mp3. I have a TC-772<\/a> USB phono preamp, which spits out a 48 kHz stereo audio stream. If you plug the USB output of the preamp into a Rapberry Pi (running Raspbian Wheezy with all the updates), it’s instantly recognized as an audio device:<\/p>\n If you install the ALSA recording utilities ( which records from the ‘pulse’ audio device, displaying a stereo text VU meter (handy for setting levels), writing to a two channel 16-bit 48 kHz file called ‘out.wav’ for a maximum of 900 seconds (15 minutes). arecord has a baffling number of recording source options; So how does it sound? Here’s a 30 second excerpt from the only single I owned for years, The Music Tapes<\/a>‘ “The Television Tells Us\/Freeing Song by Reindeer”: Freeing Song by Reindeer – excerpt<\/a> [mp3]. I’ve saved an even smaller snippet as lossless FLAC so you can see that the waveform’s pretty clean: FreeingSongbyReindeer-tiny_excerpt<\/a> [flac].<\/p>\n$ lsusb\r\nBus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub\r\nBus 001 Device 002: ID 0424:9512 Standard Microsystems Corp. \r\nBus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. \r\nBus 001 Device 004: ID 08bb:2902 Texas Instruments Japan PCM2902 Audio Codec<\/strong><\/pre>\n
sudo apt-get install alsa-utils\u00c2\u00a0pulseaudio<\/code> – this should pull in a whole bunch of necessary packages), you can record directly from this device with the following command:<\/p>\narecord -D 'pulse' -V stereo -c 2 -f dat -d 900 out.wav<\/pre>\n
arecord -L<\/code> will show them. ‘pulse’ was the first one I tried.<\/p>\n