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@JasonLG1979
Last active September 9, 2022 01:27
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/etc/asound.conf
# /etc/asound.conf
###############################################################################
pcm.hqstereo20 {
@args [
SAMPLE_RATE FORMAT BUFFER_PERIODS
BUFFER_PERIOD_TIME VOL_MIN_DB
VOL_MAX_DB VOL_RESOLUTION VOL_NAME
]
# Sampling rate in Hz:
# 44100, 48000, 88200, 96000...
# Defaults to 44.1 kHz (CD Quality).
@args.SAMPLE_RATE {
type integer
default 44100
}
# Format:
# S16_LE, S24_LE, S24_3LE, S32_LE...
# Defaults to S16_LE (CD Quality).
@args.FORMAT {
type string
default S16_LE
}
# Periods per buffer.
@args.BUFFER_PERIODS {
type integer
default 4
}
# Period size in time.
# Defaults to 125ms (0.125 sec).
# BUFFER_PERIODS * BUFFER_PERIOD_TIME = buffer time/size
@args.BUFFER_PERIOD_TIME {
type integer
default 125000
}
# Minimal dB value of the software volume control.
@args.VOL_MIN_DB {
type real
default -51.0
}
# Maximal dB value of the software volume control.
@args.VOL_MAX_DB {
type real
default 0.0
}
# How many steps between min and max volume.
@args.VOL_RESOLUTION {
type integer
default 256
}
# The name of the software volume control.
# If your card does not have hardware volume control
# naming it PCM will cause most apps that use alsa volume
# to use the software volume control.
@args.VOL_NAME {
type string
default Softvol
}
type softvol
min_dB $VOL_MIN_DB
max_dB $VOL_MAX_DB
resolution $VOL_RESOLUTION
control {
name $VOL_NAME
card {
@func refer
name defaults.ctl.card
}
}
slave.pcm {
type plug
slave.pcm {
type dmix
ipc_key {
@func refer
name defaults.pcm.ipc_key
}
ipc_gid {
@func refer
name defaults.pcm.ipc_gid
}
ipc_perm {
@func refer
name defaults.pcm.ipc_perm
}
slowptr 1
hw_ptr_alignment roundup
slave {
pcm {
type hw
nonblock {
@func refer
name defaults.pcm.nonblock
}
card {
@func refer
name defaults.pcm.card
}
device {
@func refer
name defaults.pcm.device
}
subdevice {
@func refer
name defaults.pcm.subdevice
}
}
channels 2
period_size 0
buffer_size 0
buffer_time 0
period_time $BUFFER_PERIOD_TIME
periods $BUFFER_PERIODS
rate $SAMPLE_RATE
format $FORMAT
}
bindings {
0 0
1 1
}
}
}
}
###############################################################################
# Find your sound card:
# aplay -l
# Find your card's supported format(s) and sampling rate(s) While no other audio is being played:
# aplay -Dhw:<card #>,<device #> --dump-hw-params /usr/share/sounds/alsa/Front_Right.wav
# For example:
# aplay -Dhw:0,0 --dump-hw-params /usr/share/sounds/alsa/Front_Right.wav
# The output should look something like this if the card and device combination is correct:
# ACCESS: MMAP_INTERLEAVED RW_INTERLEAVED
# FORMAT: S16_LE S24_LE S32_LE
# SUBFORMAT: STD
# SAMPLE_BITS: [16 32]
# FRAME_BITS: [32 64]
# CHANNELS: 2
# RATE: [8000 192000]
# ...
# The above card supports formats S16_LE, S24_LE, and S32_LE, at up to a sampling rate of 192000.
# Check to see if your sound card has hardware volume controls.
# amixer -c<card #> scontrols
# For example:
# amixer -c0 scontrols
# The output should look something like this if your card has hardware volume control:
# Simple mixer control 'PCM',0
# ...
# Change to the card number that you want to be the default control card.
# Default: 0
defaults.ctl.card 0
# Change to the card number that you want to be the default playback card.
# It should usually be the same as defaults.ctl.card.
# Default: 0
defaults.pcm.card 0
# Change to the device number that you want to be the default device on the default card.
# 0 or 1 is usually the correct device number.
# Default: 0
defaults.pcm.device 0
# Change to the subdevice number that you want to be the default subdevice on the default device.
# Should rarely need to be changed.
# Default: -1
defaults.pcm.subdevice -1
# To install high quality samplerate converters on Debian based systems:
# sudo apt install -y --no-install-recommends libasound2-plugins
# To list available rate_converter's:
# echo "$(ls /usr/lib/*/alsa-lib | grep "libasound_module_rate_")" | sed -e "s/^libasound_module_rate_//" -e "s/.so$//"
# Uncomment and replace speexrate_medium with the rate_converter of your choice.
# defaults.pcm.rate_converter speexrate_medium
# Once everything is configure close and save this file and test with:
# speaker-test -c2 -l1
# While audio is playing you can verify your settings with:
# cat /proc/asound/card*/pcm*p/sub*/hw_params
pcm.!default {
type empty
# Optional args:
# SAMPLE_RATE: default: 44100
# FORMAT: default: S16_LE
# BUFFER_PERIODS: default: 4
# BUFFER_PERIOD_TIME: default: 125000
# VOL_MIN_DB: default: -51.0
# VOL_MAX_DB: default: 0.0
# VOL_RESOLUTION: default: 256
# VOL_NAME: default: Softvol
# Example:
# hifiberry dac+ zero on a pi zero.
# slave.pcm "hqstereo20:FORMAT=S32_LE,BUFFER_PERIOD_TIME=250000,VOL_MIN_DB=-48.0,VOL_NAME=PCM"
slave.pcm "hqstereo20"
}
###############################################################################
ctl.!default {
type hw
card {
@func refer
name defaults.ctl.card
}
}
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