Proper mixer settings for music playback, or hardware fixes?

[Ole Kliemann]

On Fri, Jul 18, 2008 at 02:17:05PM +0300, Timo Jyrinki wrote:
> I had heard
> about some resistor in wrong place resulting in high-pass filter and
> basically making music listening unbearable.  

Do you still remember where you read it? 

I have some problems with the output of the headphone jack too. But to
me it sounds mostly distorted. 

> The initial sound quality indeed lacks all bass. However, there's a
> gigantic amount of alsamixer settings available - would these be
> documented anywhere, or has anyone been thoroughly going through
> those?
> 
> I found that Bass Filter has a scale going from most normal ("200Hz @
> 8kHz") to most thinny voice ("130Hz @ 48kHz"), but how those settings
> should be interpreted? The whole range is, in order:
> 200Hz @ 8kHz
> 100Hz @ 8kHz
> 400Hz @ 48kHz
> 100Hz @ 16kHz
> 200Hz @ 48kHz
> 130Hz @ 48kHz
> 
> Sounds weird to me.
> 
> Additionally there is a Bass settings, initially 0. And Bass Boost,
> with either "Linear Control" or "Adaptive Boost". With Bass set to 100
> and Bass Boost set to Adapative Boost, together with "200Hz @ 8kHz"
> setting, the sound is starting to resemble something of a normal,
> though quite far from ideal. Linear Control is probably better,
> Adaptive Boost seems to clip sometimes with heavy bass.

It seemed to me the bass problem could be solved by mixer setting. But I
could not remove the distortion in the mid to higher frequencies.
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