[sound]: capacitor that act like a high-pass filter and so removes the bass on the headphones jack

GNUtoo at no-log.org GNUtoo at no-log.org
Sat Nov 15 15:26:30 CET 2008

Hello, I've the same issue as described here:
That is to say the "Poor low-frequency audio response with low-impedance
headphones" problem...
On IRC I was told that was the fault of a capacitor that lies between the
audio chip and the headphones jack that is too low and act like a
high-pass filter and so removes the bass...

This issue is very problematic for me:
I've a pma430 that I use like an audio player(linux device with
proprietary kernel modules and an old proprietary version of qtopia)...but
it's an old device...and one day the battery will die...
Moreover it has a lot of bugs that I can't get rid of:
*mplayer for the pma430 is buggy and I don't have its sources(it's a
special port because the sound drivers are buggy or specials...)
*the default player is buggy and I often have to restart the device
*the suspend button is often pressed when the device is in my pocket...and
because of the proprietary nature of the device I don't think this could
be changed...otherwise the openpma devellopers would have changed that...
So buying an openmoko I thought that I would get a device that would
replace it as:
*a real GNU/Linux pda(done(the compiler of the pma430 couldn't be changed
because of a kernel bug and the kernel couldn't be changed because of the
proprietary modules,but with openmoko we have openembedded and a lot of
*an audio player(here's the problem)

The problem is that the software fix suggested by the wiki isn't
sufficient for proper audio quality...

So what are my options?
solder myself the capacitor isn't an option...I'm not skilled enough nor
have the right soldering iron(Long time ago I've broken a graphic card
trying to do a mod that would make the nvidia drivers recognize the card
as a quadro card...(the card was sometimes recognized by the 3d driver and
sometimes not))
So what sould I do?
find a shop or someone that would do it for me(I live in Milan in Italy)?
use the guarantee(I bought it at bearstech)?
Or would a better software fix be possible(such as re-encoding the ogg
with special filters?,but that would be problematic as it would use a lot
of space for keeping the files on my computer...but if it's the only
option I'll use it)
adding an external sound card isn't an option either because if I use it
in my home on a hifi-set I would not be able to feed the openmoko in
power(as the usb port would be taken by the audio card) or if I use it
outside...a sound card isn't very compact...
By the way for determining the version of my hardware, I think I've got
the hardware fix for the GPS and I bought a released version of the GTA02
Thanks a lot in advance for your help.

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