[LAU] Mono tracks to mono or stereo bus ? And sampling rate

jonetsu at teksavvy.com jonetsu at teksavvy.com
Mon Nov 23 16:33:44 UTC 2015

On Mon, 23 Nov 2015 11:18:32 -0500
Joe Hartley <jh at brainiac.com> wrote:

> Your session runs at a sample rate set by JACK.  All the files that
> have audio in them  have to match that value.  If the audio you want
> to use has a higher sample rate, it will have to be re-sampled at the
> lower rate for Ardour to use it in that session.

Sure.  Thing is, I sample, eg. I record in Ardour only.  So I only
speak of Ardour.

> If you want to have JACK and Ardour run at the higher sample rate,
> assuming your interface supports it, you'd have to create a new
> session and import the tracks.  The files with the audio that match
> that new, higher rate will be imported with minimal processing, while
> the other tracks will be up-sampled.

This "up-sample" as far as I understood from the course, does not exist
in reality as far as the quality of audio is concerned.  A
demonstration can be easily made using Audacity and zooming up to see
the actual sampling points of both files, the original and the
"up-sampled": the file that has been resampled from lower sampling rate
will not add anything at all but more sampling points on straight
segments of the audio.  It cannot add quality. It cannot create curves.

What I mean by using a higher sampling rate is for recording purposes.
To have more points being sampled when a guitar is played.  So that the
points can represent closer sections of the wave instead of jumping and
making straight lines.
> There is no way for Ardour to use files of a different sample rate
> without them being resampled to the rate of the session, as
> determined by JACK's setting.

Which would not be right as it will be better to re-record the tracks
that actually need a better quality of sampling.  

Out of say 15 tracks, there would be 4 that need higher quality
sampling because they are acoustic instruments.  But the 15 tracks,
even the synths and synth drums, will take so many more megabytes of
space, because the sampling rate is not set on a per track basis.
Maybe sampling rates on a per-track basis does not make sense in FAWs
in general.

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