Volume levels in mixer are not correctly defined
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
alsa-utils (Ubuntu) |
Invalid
|
Undecided
|
Unassigned | ||
gnome-alsamixer (Ubuntu) |
Invalid
|
Medium
|
Unassigned | ||
linux (Ubuntu) |
Expired
|
Undecided
|
Unassigned |
Bug Description
Alsa mixer in Dapper Beta:
This bug could make a user think that sound is broken.
- Choose an audio file with high volume (any modern track that is normalized will do) and play it, in a loud part.
- Open mixer
- Set PCM to 80% and Master to 100%. Sound is OK
- Set PCM to 100% and Master to 80%. Sound is distorted.
Conclusions:
- PCM and Master volume values mean different things. Not a good idea.
- Master volume values seem OK.
- PCM current value "80%" should correspond to "100%", because above this point clipping occurs with normalized files. Maybe it is not exactly 80%, but very close.
- Values above this point are useful to deal with audio files with low volume, but should be marked >100% to reflect that clipping may occur.
- Maybe Values above 100% should be considered for Master also.
- There should be something in the mixer that indicates clearly that we are above 100% volume (a line, or maybe changing slider color to red)
- Numerical values for volume should be shown in mixer window, as they are shown in volume applet in taskbar, or permanently.
Some of this things may apply to input volumes.
I've been experiencing this problem too for a *long* time now, ever since Breezy IIRC. I came across the solution the parent suggested, but it would be nice to see a permanent solution or even a 'fixed' hack to resolve this. People on the Ubuntu forums suggested you can get the 'max' value for PCM volume in a configuration file... currently looking into it. This may not be an issue for most, but for people who have high quality home theater soundsystems hooked up to Ubuntu might not be too happy.