Raspbian - MPD ALSA volume control too rough

6 posts
by SPGremlin » Tue Oct 23, 2012 9:32 pm
I'm using clean fresh Raspbian Wheezy image (downloaded from this site earlier this week).

Installed MPD. The volume control in MPD (through mpc or other clients) works, and is reflected to the "alsamixer" settings. The problem is, it is reflected too rough:

75% volume in MPD = 36% in ALSAMIXER = "-22.58" db gain, barely hearing sound
85% volume in MPD = 54% in ALSAMIXER = "-11.94" db gain, low sound
90% volume in MPD = 67% in ALSAMIXER = "-6.62" db gain, quite low sound
95% volume in MPD = 82% in ALSAMIXER = "-1.30" db gain, moderate sound
100% volume in MPD = 100% in ALSAMIXER = "-4.0" db gain, normal sound

The problem is, my client of choice - "MPoD" for Iphone only allows controlling MPD volume settings by 5% step, which goes far too rough, I'm left with only 2-3 steps before sound goes too low.

Does anyone here know a way to remap MPD volume on alsa volume in more smooth (linear) way?
Posts: 4
Joined: Tue Oct 23, 2012 6:56 pm
by SPGremlin » Fri Oct 26, 2012 9:33 am
Does anybody else at least observe similar behavior? Does anybody else consider this behavior erroneous?
Posts: 4
Joined: Tue Oct 23, 2012 6:56 pm
by jonathanmt » Tue Oct 30, 2012 12:23 pm
I had a similar problem and resolved by using a software mixer.

I just uncommented the below line in /etc/mpd.conf.
Code: Select all
mixer_type                      "software"
Posts: 1
Joined: Tue Oct 30, 2012 12:21 pm
by SPGremlin » Sat Nov 03, 2012 3:15 pm
Thank you! This helped.

The volume gets overall low this way (I have to put speakers hardware switch higher then usual), but this is still much better then before.
Posts: 4
Joined: Tue Oct 23, 2012 6:56 pm
by NeilScudder » Sun Jul 20, 2014 6:24 pm
I'm having the same problem, and I can't use the software mixer because I want to pipe the audio through some LADSPA plugins first and affect the master volume afterwords. I will post the solution if I can find it.

Raspi Model B+, Raspbian (kernel 3.12.24+)
Posts: 2
Joined: Sun Jul 20, 2014 6:21 pm
by NeilScudder » Sun Jul 20, 2014 7:17 pm
I am having the same problem, but I can't use the software mixer as doing so would lower my input volume to a chain of LADSPA plugins. Using the hardware mixer and reducing the volume using 'mpc volume -10' starting at 100 yields these results in alsamixer:

Which is an interesting scale, seems to be more in line with the way sound and decibels actually work in terms of amplitude. FTM I am going to compensate artificially since the volume still works, and re-write the mpd volume value to reflect.
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Joined: Sun Jul 20, 2014 6:21 pm