Poor sound quality under linux?

Doug ABERDEEN douglas.aberdeen at anu.edu.au
Tue Jun 25 21:25:44 EST 2002

Hi Guru's

I've noticed that sound quality under my Linux setup is generally 
poorer than Windows and I'm after some tips to make it sound better.

Symptoms:  Under xmms, mpg123, xine, artsd, games like Tux Racer, I get what 
           sounds like white noise and high frequency distortion 
           mixed in with the audio. It's still listenable, but 
           poor enough to irritate me quickly. I thought it might be 
           down-sampling somwhere but when I forced mpg123 to 
           downsample and then it sounded really crap ;) The sound quality 
           under Windows is as good as I would expect
           from on m/board audio and much better than the Linux sound.
           Now that DVD's are perfectly watchable under Linux, the sound 
           quality is about the last thing preventing me from 
           running % rm -fr /mnt/windows
Setup:     VIA 8233 on m/board sound, Mandrake 8.1 base, kernel 2.4.18,
           I compiled ALSA 0.9.0rc1 to get support for my card.
           I've also got all the OSS emulation stuff associated with
           ALSA 0.9.0rc1. I've included the contents of 
           /proc/asound/card0/ac97#0 below for those of you with 
           detail fetishes.

Tried:     I tried the following without success:
		o Running under real-time priority
		o Tweaking the mixer settings
                o Using the xmms artsd plugin instead of the OSS plugin

Questions: I think the quality under xine might be better than xmms. 
	   It's sometimes a little difficult to distinguish crappy decoding 
           from crappy encoding. A significant factor might be that xine uses 
           the ALSA interface directly, instead of going through the 
           OSS emulation interface like all the other progs I mentioned. 
	   Has anyone else using ALSA noticed that OSS emulation sucks?

	   Is it possible that it's just a crappy driver?

	   Is, may the gods forbid, linux sound just crap?

	   Does anyone know any magic tweaks to make it all sound perfect?


[daa at gradhouse32 card0]$ cat ac97#0
0-0/0: Avance Logic ALC200/200P

Capabilities     : -headphone out-
DAC resolution   : 18-bit
ADC resolution   : 18-bit
3D enhancement   : Realtek 3D Stereo Enhancement

Current setup
Mic gain         : +0dB [+0dB]
POP path         : pre 3D
Sim. stereo      : off
3D enhancement   : off
Loudness         : off
Mono output      : MIX
Mic select       : Mic1
ADC/DAC loopback : off
Extended ID      : codec=0 rev=1 AMAP DSA=0 SPDIF VRA
Extended status  : SPDIF=3/4 SPDIF VRA
PCM front DAC    : 44100Hz
PCM ADC          : 48000Hz
SPDIF Control    : Consumer PCM Copyright Category=0x2 Generation=1 Rate=48kHz

-Doug  -- http://csl.anu.edu.au/~daa, Ph: (02) 6125 8608
The best-trained dog may not obey its master, but no one then will say
that the dog is 'defective,' yet that is exactly what they call 
a computer that operates contrary to its program. 
					[Doctor Diagoras, Stanislaw Lem]

More information about the linux mailing list