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hpr3507 :: USB Turntable fix and sound journey

USB Turntable fix and sound journey with arecord, asound and ffmpeg

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Hosted by Archer72 on 2022-01-11 is flagged as Clean and is released under a CC-BY-SA license.
Vinyl, album, Vinyl album, record album, aplay, arecord, alsaloop, ffmpeg,retro, USB turntable. (Be the first).

Listen in ogg, spx, or mp3 format. Play now:

Duration: 00:08:48


Partial list of albums

  • Journey - Frontiers
  • Journey - Evolution
  • Journey - Greatest Hits
  • Journey - Departure
  • Chicago - 2 albums - unknown titles
  • John Denver - Rocky Mountain Christmas
  • Inside Star Trek (1976)
    • SIDE I Inside Star Trek Star Trek Theme William Shatner Meets Captain Kirk The Origin of Spock Sarek's Son Spock The Questor Affair
    • SIDE II The Enterprise Runs Aground McCoy's Rx for Life The Star Trek Philosophy Asimov's World of Science Fiction A Letter From a Network Censor The Star Trek Dream Ballad I/Ballad II)*

Inside Star Trek album: Cover
Inside Star Trek album: Cover
Click the thumbnail to see the full-sized image - -

Inside Star Trek album: Contents
Inside Star Trek album: Contents
Click the thumbnail to see the full-sized image - -

I found a turntable at the thrift store, and the spindle ran, but the platter did not. The belt had slipped off, and here is the fix.

How to remove platter
How to remove platter
Click the thumbnail to see the full-sized image - -

Belt placement
Belt placement
Click the thumbnail to see the full-sized image - -

Routing Audio from a USB Turntable to HDMI using a Raspberry Pi

Send input to output

alsaloop -t 500000 -C hw:CARD=CODEC,DEV=0 -P default:CARD=b1

alsaloop man page

Parameter b1 is found by

pi@retropie:~ $ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: b1 [bcm2835 HDMI 1], device 0: bcm2835 HDMI 1 [bcm2835 HDMI 1]

Raspberry Pi as a USB audio capture device

Used hw:CARD=CODEC,DEV=0 derived from 'arecord -L'

USB Audio CODEC, USB Audio
Direct hardware device without any conversions

arecord man page

   -D, --device=NAME
    Select PCM by name
    -V, --vumeter=TYPE
    Specifies the VU-meter type, either stereo or mono. The stereo VU-meter is available only for 2-channel stereo samples with interleaved format.
    -c, --channels=#
    The number of channels. The default is one channel. Valid values are 1 through 32.
    -f --format=FORMAT
    Sample format
    Recognized sample formats are: S8 U8 S16_LE S16_BE U16_LE U16_BE S24_LE S24_BE U24_LE U24_BE S32_LE S32_BE U32_LE U32_BE FLOAT_LE FLOAT_BE FLOAT64_LE FLOAT64_BE IEC958_SUBFRAME_LE IEC958_SUBFRAME_BE MU_LAW A_LAW IMA_ADPCM MPEG GSM SPECIAL S24_3LE S24_3BE U24_3LE U24_3BE S20_3LE S20_3BE U20_3LE U20_3BE S18_3LE S18_3BE U18_3LE
    Some of these may not be available on selected hardware
    The available format shortcuts are:

    -f cd (16 bit little endian, 44100, stereo) [-f S16_LE -c2 -r44100]
    -f cdr (16 bit big endian, 44100, stereo) [-f S16_BE -c2 -f44100]
    -f dat (16 bit little endian, 48000, stereo) [-f S16_LE -c2 -r48000]

Recording to FLAC

How can one record mic audio straight to a FLAC file?

ffmpeg -f alsa -ar 48000 -ac 1 -i hw:0 testfile.flac

Took out the "-ac 1", which downmixed the input to mono

Change hw:0 to hw:2 based on

pi@retropie:~/vinyl $ arecord -l
**** List of CAPTURE Hardware Devices ****
card 2: USB20 [AV TO USB2.0], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0

ffmpeg -f alsa -ar 48000 -i hw:2 testfile_stereo.flac

FFmpeg Audio Channel Manipulation


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