05-16-2025, 05:36 PM
Hello Tim,
I did not realize that this question is akin to prying out a trade secret and I aplogize for any inconvenience.
In the "Audio Information" display, volume levels are reported in dB (eg, "Volume levelsKnob 90, ALSA -3.00dB, CDSP -6dB").
I want to set ALSA level in "Audio Settings" to a specific value in dB.
A value of 89 is entered for a HiFiBerry DSP+ ADC Pro to get the -3dB shown above.
If using the HDMI port connected to a RaspBerry Pi Monitor, a value of 87 must be entered to obtain the -3dB level (even if this device is using a strictly linear function to calculate its gain, as shown below).
Would it be possible to enter the desired volume level in "Audio Settings" rather than what looks like a magic number to obtain this result ?
Regards,
I did not realize that this question is akin to prying out a trade secret and I aplogize for any inconvenience.
In the "Audio Information" display, volume levels are reported in dB (eg, "Volume levelsKnob 90, ALSA -3.00dB, CDSP -6dB").
I want to set ALSA level in "Audio Settings" to a specific value in dB.
A value of 89 is entered for a HiFiBerry DSP+ ADC Pro to get the -3dB shown above.
If using the HDMI port connected to a RaspBerry Pi Monitor, a value of 87 must be entered to obtain the -3dB level (even if this device is using a strictly linear function to calculate its gain, as shown below).
Would it be possible to enter the desired volume level in "Audio Settings" rather than what looks like a magic number to obtain this result ?
Regards,
Code:
musical@moOde:~ $ amixer -c vc4hdmi1 contents
[ ... ]
numid=6,iface=MIXER,name='PCM Playback Volume'
; type=INTEGER,access=rw---RW-,values=2,min=0,max=255,step=0
: values=240,240
| dBscale-min=-51.00dB,step=0.20dB,mute=0
[ ... ]