Default decibel range off by a factor of 100

[markubiak]

Using 0.0.3 on a Raspberry Pi 2 to an external DAC. The --dbrange setting only worked with a value of 1. Upon inspection of the commit that added --dbrange, I changed the line +volume_range = (mixer.getrange()[1]-mixer.getrange()[0]) / 100 to +volume_range = (mixer.getrange()[1]-mixer.getrange()[0]) which resolved the issue.

[cadavre]

Confirmed. Removing / 100 allowed me to set --dbrange 53 for my DAC.

[Nosskirneh]

I also have the issue that the range off is completely off.

When removing / 100 I now get that all steps are 99 (besides the two end-points). I've tried different options for --dbrange but in my opinion that setting lacks explanation.

Like this:

corected_playback_volume: 100
playback_volume: 64879
corected_playback_volume: 99
playback_volume: 64224
corected_playback_volume: 99
playback_volume: 61602
corected_playback_volume: 99
playback_volume: 58981
corected_playback_volume: 99
playback_volume: 55704
corected_playback_volume: 99
playback_volume: 51772
corected_playback_volume: 99
playback_volume: 49151
corected_playback_volume: 99
playback_volume: 46529
corected_playback_volume: 99
playback_volume: 45219
corected_playback_volume: 99
playback_volume: 42597
corected_playback_volume: 99
playback_volume: 39321
corected_playback_volume: 99
playback_volume: 37354
corected_playback_volume: 99
playback_volume: 35388
corected_playback_volume: 99
playback_volume: 34733
corected_playback_volume: 99
playback_volume: 32112
corected_playback_volume: 99
playback_volume: 29490
corected_playback_volume: 99
playback_volume: 28180
corected_playback_volume: 99
playback_volume: 24903
corected_playback_volume: 99
playback_volume: 21626
corected_playback_volume: 99
playback_volume: 18349
corected_playback_volume: 99
playback_volume: 12451
corected_playback_volume: 99
playback_volume: 3932
corected_playback_volume: 99
playback_volume: 0
Mute activated

I'm using amixer to enable AUX audio output: amixer cset numid=3 1

numid=3,iface=MIXER,name='PCM Playback Route'
  ; type=INTEGER,access=rw------,values=1,min=0,max=2,step=0
  : values=1

and from searching online I figure that the min=0 and max=2 seems weird. Could this be the issue?

Using OpenELEC (Rasplex) with spotify-connect-web 0.0.3.

[awiouy]

amixer cset numid=3 1 sets the playback route (0 is autodetect, 1 is jack, 2 is HDMI).

To set the volume use amixer set PCM 100%

[Nosskirneh]

Thank you for answering. Maybe I misunderstood OP's first problem, thought maybe it could've been the same since I thought it had to do with --dbrange. Yes, I know what the amixer command does - what I'm trying to do is to make the volume scale to be more linear. Right now it's like this: 0                        0    20           100 ████████████████████

or with --dbrange 50: 0    100                                   100 ████████████████████

What I however want: 0  20 30 40  50  60  70 80 90  100 ████████████████████

[Nosskirneh]

Nevermind, I fixed it.

For anyone else having the same issue, this was that I did:

RasPlex:~ # amixer controls
numid=3,iface=MIXER,name='PCM Playback Route'
numid=2,iface=MIXER,name='PCM Playback Switch'
numid=1,iface=MIXER,name='PCM Playback Volume'
numid=5,iface=PCM,name='IEC958 Playback Con Mask'
numid=4,iface=PCM,name='IEC958 Playback Default'

using numid=1 instead of numid=3 did give better values on minand max.

numid=1,iface=MIXER,name='PCM Playback Volume'
  ; type=INTEGER,access=rw---R--,values=1,min=-10239,max=400,step=0
  : values=1
  | dBscale-min=-102.39dB,step=0.01dB,mute=1

--dbrange 25 turned out to be most fitting audio scale.

[karlvr]

I think the right fix to the dbrange issue is to scale selected_volume_range rather than remove the scale on volume_range? I have made a PR for it #116

[karlvr]

Apologies, there is of course no difference between scaling one or the other! I think it is valuable to use floating point division though: updated the PR.