[LAU] Rendering multiple midi files for mixing

[S. Massy]

On Thu, Feb 03, 2011 at 03:12:29PM +0100, Alexandre Ratchov wrote:
> On Wed, Feb 02, 2011 at 03:06:35PM -0500, S. Massy wrote:
> > All right,
> > 
> > Here's another installment in the never-ending questions series.
> > 
> > I have tracks sequenced in individual midi files meant to be rendered
> > using various softsynths/patches. The idea is to:
> > 1. Send the midi data to the synth using pmidi or midish.
> > 2. Record the output from the jack ports to disk.
> > 3. Repeat 1 and 2 for each track.
> > 4. Import the tracks and mix them, possibly recording live material on
> >    top of it.
> >
> 
> Couldn't ardour do all four steps?
Possibly, but Ardour is GUI based and not easy to use, even through orca
screen-reader.

> 
> > Of these, step 2 is the tricky part. Recording the output is easy enough
> > with ecasound or even jackrec, but the problem is that there is a gap of
> > silence between the time recording is started and the time the synth
> > starts playing, thus making syncing the tracks a very tedious job. Is
> > there a simple way of recording only when audio data is coming out of
> > the jack ports?
> 
> Yeah, the purpose of MTC/MMC is to solve this problem.
> 
> You could configure midish to be the MMC master and MTC slave, and use
> a MTC/MMC capable audio recorder configured as MMC slave and MTC
> master. You'd have to start the recorder first (it waits for the MMC
> start event) and then start playback in midish (generates the MMC
> start event), both will start synchronously and stay in sync. This
> worked for me many times.
> 
> Unfortunately, I can't point you to a MTC and MMC capable recorder for
> linux, sorry. Again, ardour seems MTC/MMC capable. There are also
> jack-transport to mtc/mmc gateways, but I've never used them
> either.
The way to do it in the end was to use jackctlMMC to bridge between MMC
and jack-transport, then start ecasound in jack-transport slave mode.
Then just hitting "p" in rmidish does the trick.

Thanks for pointing me in the right direction.

Cheers,
S.M.

> 
> HTH
> 
> -- Alexandre
>