[CM] noise reduction with snd

Fri, 23 Aug 2002 10:59:11 +0200

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Ralf,

Yes, my problem is speech recordings. The equipment is certainly the main s=
ource of noise, but I think the presence of computers and screens also caus=
e a constant background noise.

Most tools mentioned so far (thanks to everyone for all these ideas !) do n=
ot seem to enhance the quality significantly (or I'm not using them correct=
ly...).

I think you're right in saying that I might "just" need to isolate the spee=
ch, but that was part of my question. As I am a complete newbie in the fiel=
d, I don't really know what "apply both a lowpath and a highpath to the ori=
ginal signal" means. I understand the concept, but I don't know what this m=
eans in practice. That's why I asked about info in that direction. So, if y=
ou have some references or some general tips on how to approach this that w=
ould be good.

Moritz

On Fri, Aug 23, 2002 at 10:45:58AM +0200, rm@fabula.de wrote:
> Let me jump out  of my lurking state here ...
> If i understand the original poster's question right he i
> asking about background noise removal from speech recordings. The tools
> mentioned so far are probably nice to remove scratches and dust noise
> from old vinyl recordings but probably not so good for the task under
> discussion.
> Moritz, you forgot to mention where the noise on the tapes(?) comes
> from. Is it environmental noise or is it noise introduced by the
> probably bad recording equipment. If you just need to isolate the
> speech part to get a clearer understanding of the text you might be
> able to use the ol' telephone trick: human speech stays comprehensible
> even if one removes major parts of the spectrum. You could apply both
> a lowpath and a highpath to the original signal, and, unless your noise
> happens to be in the same area of the frequency spectrum as the speech
> component, get a much more understandable speech signal. It's been quite
> a while since a last worked with/looked at human speech, if you need more
> help send my an email and i'll try to dig up some notes/literature.
>=20
>  Ralf Mattes
>=20
> On Thu, Aug 22, 2002 at 07:02:35PM -0600, kelly george hirai wrote:
> > csound comes with an outboard de-noiser called denoise. i have used it
> > with much success to get rid of hiss. check the comand line parms for b=
est
> > results, the default settings are not very good. kelly
> >=20
> > On Fri, 16 Aug 2002, Michael Edwards wrote:
> >=20
> > > Hi Moritz,
> > >
> > > Noise removal is a very tricky business, way over my head to be hones=
t,
> > > but I found a nice little app that's idiot-proof (there's only one
> > > slider to fiddle with) and costs only $20.  I'm sure a lot people will
> > > find it too limiting but I've done many a clean-up job with it and sw=
ear
> > > by it.  You'll find it below:
> > >
> > > http://www.excla.com/WAVclean/English/
> > >
> > > Good luck,
> > >
> > > 	Michael
> > >
> > >
> > > mlennert@club.worldonline.be schrieb:
> > > >
> > > > Hello,
> > > >
> > > > I am a complete newbie in the field of sound editing, so please tel=
l me if I'm completely out of my league and if this isn't the right place t=
o ask these questions.
> > > >
> > > > I have been conducting interviews for my MSc dissertation and am no=
w in the process of transcribing them. However, my recordings are not alway=
s of very good quality and I often have heavy background noise. Since this =
noise is quite constant and homogenous, I was wondering whether it would be=
 possible to filter it out in order to hear the voices more clearly. I've t=
ried some noise reduction with 'audacity', but the result was not extraordi=
nary. Is it possible to reduce noise in snd ? And if yes, could someone jus=
t briefly list the steps I have to follow, or a source of information about=
 this ? I have read through the manual, but since I'm not familiar with the=
 vocabulary of sound engineering this is not always easy.
> > > >
> > > > So any hint would be welcome.
> > > >
> > > > Thanks in advance !
> > > >
> > > > Moritz
> > > >
> > > >   -----------------------------------------------------------------=
-------
> > > >    Part 1.2Type: application/pgp-signature
> > > _______________________________________________
> > > Cmdist mailing list
> > > Cmdist@ccrma.stanford.edu
> > > http://ccrma-mail.stanford.edu/mailman/listinfo/cmdist
> > >
> >=20
> > kelly, angel, riley & cameron hirai
> > 343 Pennell Circle #3 Tallahasse FL 32310  usa
> > http://www.unm.edu/~khirai
> > "... because writing music is easier than running the world." Jim Atkins
> >=20
> > _______________________________________________
> > Cmdist mailing list
> > Cmdist@ccrma.stanford.edu
> > http://ccrma-mail.stanford.edu/mailman/listinfo/cmdist
> _______________________________________________
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