Pulseaudio SPDIF Input, LFE remix

Route the SPDIF input of the Aureon 5.1 USB Soundcard to its 5.1 output

For my ESP32 Bluetooth to Toslink Project, start this

arecord -f S16_LE -c 2 -r 48000 -D iec958  --disable-channels --disable-format --disable-softvol --disable-resample -B 100000 -t raw | \
aplay   -f S16_LE -c 2 -r 44100 -D default --disable-channels --disable-format --disable-softvol --disable-resample -B 100000 -t raw

Bit strange: BT A2DP sends 44100 samples/s but iec958 seems to be locked to 48000, so fix speed during output or voices are a bit too high

For a good sound, the LFE needs to do some work for the small satelites

/etc/pulse/daemon.conf

enable-lfe-remixing = yes
lfe-crossover-freq = 100

To enable changes

systemctl --user restart pulseaudio.service

Loopback line in to line out

PulseAudio Control

This has long delay

Start Loopback

• pactl load-module module-loopback

Stop loopback

• pactl unload-module module-loopback

PulseAudio Cat

This can have short delay

Install pulseaudio manager to look for the audio device names, then write script to start the monitoring with short delay

• sudo zypper in paman
• paman -> look at property of sink and source (to copy/paste the long names)
• write script to start monitoring

 pacat -r --latency-msec=1 -d 'alsa_input.usb-FMIC_Fender_Mustang_Micro_396234823131-00.iec958-stereo' | \
 pacat -p --latency-msec=1 -d 'alsa_output.usb-0ccd_USB_Audio-00.analog-surround-51'