How do I offline / non-realtime mixdown?

How do I offline / non-realtime mixdown?

in export dialogue:

  • realtime is NOT ticked
  • channels ticked are master out-1 + out-2
  • the result is fine, but it’s SLOW… why?

I’m using the latest wndows nightly version.

It’s “as fast as possible, as slow as necessary”.

Perhaps the session is rather heavy to begin with?

  • What is the DSP load (indicator top-right) under normal operation?
  • When exporting it should be 100% (as fast as possible)

Maybe writing the file to disk is slow? Is this a local HDD or SSD?
Or perhaps encoding (flac, mp3) is the bottleneck? What format have you selected?

How slow is it compared to realtime playback?

Playback DSP spends most time in the 50-70% zone, spikes in the 90, dips in the 40.
Data is on an SSD.
Export DSP is exactly 86%
It actually looks a little faster than realtime.
It’s set to use all available processors.
Export file format is CD wav format from the dropdown.
Source files are 96khz 16bit.

That is odd. What backend do you use? JACK? If so, can you check if using ALSA (or Dummy or pulseaudio in Menu > WIndow > Audio/MIDI Setup) makes a difference?

1 Like

@x42 The OP is on Windows.

@PatienceAllergy So to translate what x42 said, are you using Jack, and if so can you try with the dummy or ASIO backends instead and see if there is a difference? Or if you are on ASIO try with the dummy backend if you have that?

1 Like

yup, I’m using Windows for this project. So no PulseAudio here…

Although my windows machine is actually running the never fully developed Windows version of the PulseAudio drivers, just to receive audio piped over ethernet from my linux machine.

Yes! I’m using JACK.

On Dummy driver in JACK, export stayed at an exact 89%.

Is there a special ASIO driver I can select in the JACK driver setup? I only see Port Audio, Net JACK and Dummy. If so, where do I get this driver?

Thanks for your help ya’ll!

I meant Ardour’s Dummy driver (however on Windows that is hidden). I suspect that JACK is the issue. So using some other backend would provide info if this is the case.

Can you try Ardour’s Portaudio backend, then?

Sure, so I tried the Portaudio driver instead of JACK, and the DSP ran at 100% during export!

So, any idea what this tells us? Do I have to change audio driver to export at max speed?

Does it export faster than realtime too?

On Linux there are some known edge-cases where JACK does not correctly switch to “freewheel” (process as past as possible) mode, and I suspect a similar bug also exists on Windows version.

Is there a reason why you want or need JACK on Windows? Ardour’s ASIO backend should perform better.

1 Like

Nope, I don’t need JACK. I assumed it was the best option, but I guess not!

Yes, it definitely exported faster than realtime, and I would say faster than the JACK options.

Thanks for solving my problem!

Is there ever a time, on Windows, that JACK would be the preferred way?

Same reason on Linux and macOS: You only need JACK if you want to route audio between JACK applications (like ReWire), or share the soundcard with other JACK apps.

In the distant past JACK was required, but since Ardour 3.5 (October 2013) that is no longer the case. Sadly a lot of tutorials and online reference still promote the old way.

1 Like

This topic was automatically closed 91 days after the last reply. New replies are no longer allowed.