Henrik
Sun Jun 10 17:13:38 CDT 2007
I don't have any experience with the wm8976 but Ive been involved in
designing a couple of hi-end audio devices in the past so here goes;
First of all, noise is a pretty vague description. Is it stocastic
white/pink continous background noise? Is it aperiodic glitches?
50/60Hz humming perhaps? Is it distortion rather than noise?
For exampe recording a weak signal such as a microphone and then
digitally amplifying it will create noise -usually both background
noise and quantisation distortion. Recording a (too) strong signal
that saturate the AD will create a higly distorted recording.
What kind of application is it? Hi-end audio gear or a simple sound-
recorder-would-be-a-nice-feature kind of device? How did you verify
that the signal from the wm8976 ADC output is OK? By measuring or by
listening to it? Have you done any measurements on distortion and S/N
ratio?
Henrik Viklund
http://www.addlogic.se
On Jun 9, 4:19 am, desirecha...@21cn.com wrote:
> On 6 8 , 9 31 , desirecha...@21cn.com wrote:
>
> > On 6 8 , 4 24 , desirecha...@21cn.com wrote:> hello,
> > > my platform is s3c2442+wince 5.0 +wolfson wm8976 codec,and i
> > > develope the wav driver based on the structure of driver MS
> > > provided(public/oak/s3c2410/wavdev), and now the playback part is
> > > ok,when it play mp3 file,the sound is good.
> > > but when I use the wavrec.exe to record,it got some noise.and
> > > the digital signal from wm8976 ADC is ok,no such noise,but when it
> > > record to wavrec.wav and then play it.it get noise
> > > and in the wavrec.exe,it setting:
> > > channels =1,bitspersample =16,samplerate =44100 (the wm8976 has
> > > only a ADC)
> > > where is the noise from?can anybody give some help?what's the function
> > > render2() in input.cpp
>
> > can any body give some help
>
> anybody give some help?