[LAU] DC offset

[Rustom Mody]

On Mon, Jan 30, 2012 at 2:03 PM, Fons Adriaensen <fons at linuxaudio.org>wrote:

> On Mon, Jan 30, 2012 at 08:41:28AM +0530, Rustom Mody wrote:
>
> > Immediate context:
> > Im trying to capture from firefox using the .asoundrc/jack settings shown
> > http://jackaudio.org/routing_alsa
> > [Track is http://www.raaga.com/play/?id=183659
> > I would just buy it if it were for sale; its not. You may have to click
> > past an ad]
>
> I just recorded the first minute using the alsa-jack plugin, this
> works perfectly and their is no offset in the signal. So it's not
> the source or firefox or the plugin.
>
> > However Ive noticed earlier that when I use my (cheap headset) mike to
> > record directly into audacity, this similar DC offset occurs. Since I am
> no
> > audio pro I did not know what to google for before seeing the tabs in the
> > normalize dialog of audacity.
>
> Could it be that while recording from firefox you had the soundcard
> (auto)connected to the same track as well ? That would add the offset
> if the cause is your soundcard (which I suspect), even if the headset
> is not plugged in.
>

So you are suggesting I "unconnect" the soundcard (and 'silently' record?)
Ok how to unconnect the card?


>
> > So if you ask me exactly how much DC offset I dont know how to find out
> in
> > figures.  The audacity track shows it 1/4th to 1/3rd way up. Center is
> 0.0
> > top is 1.0 inbetween is 0.5.
> > This is little more than half way between 0 and 0.5.
>
> Which is way too much, and indicates broken hardware.
>
> So please check your connections and then we'll see again.
>

Not sure what you are asking here...
What I can try is a friends machine...
Let me try that (Some challenges to that I am the most 'pro' out here in
the sense that I at least know how to spell j-a-c-k :-) -- I guess I'll
just commandeer the machine.




> Ciao,
>
> --
> FA
>
> Vor uns liegt ein weites Tal, die Sonne scheint - ein Glitzerstrahl.
>
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