Sound quality changed by Kdenlive & LiVES

[lrspares45]

On Sat, 2010-01-23 at 13:44 +0100, Hartmut Noack wrote:
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> Am 23.01.2010 12:58, schrieb lrspares45:
> > Has anyone else come across this? I have an mp3, recorded with Ardour,
> > of me playing through BOSS Blues Driver - so far so good.
> > 
> > I then used Kdenlive to create a video, but noticed that Kdenlive had
> > noticeably cleaned up the sound (taken away some of the fuzz so to
> > speak), to the extent that the music sounds all wrong. LiVES then did
> > the same thing! Both have everything at default, i.e. as installed. 
> > 
> > Is there a way of making either app leave the sound alone
> 
> I guess so. But its only guessing: You should never, never ever compress
> a soundfile to MP3 or ogg if you plan to use it for anything else but
> listening to it. Always use uncompressed WAV if you export a file to be
> used in another app.
> If the same data is compressed twice (first after exporting from Ardour
> then again if exported from KDEnlive) the sound is bound to suffer.
> You also should use the samplerate you plan to use in the Video, if you
> export a file for soundtrack-purposes. 48KHz that is, even the jump from
> a 44.1-file to 48 produces liestenable artifacts since the missing 400Hz
> of data need to be interpolated.
> 
> best of luck, and keep us informed, weather this works or not...
> :-)

Ah! It hadn't occurred to me that the mp3 is being compressed again...
that would certainly explain why both do the same to the sound.

I'll have a play.

Cheers
Richard


> 
> >, or is it just
> > the way it is?
> > 
> > Cheers
> > Richard
> > 
> > 
> 
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