First up in the latency/jitter testing is Pro Tools!

If you don’t understand what this is, please read the introduction post (This article is being updated if/when changes are made!).

Contents

Introduction

Read the introduction post. I have updated this post since it was originally published.

For Pro Tools I used Kontakt 6 since there is not a native Pro Tools sampler.

The only setting I found that changed results was Settings->Playback Engine->Minimize I/O Latency.

Reminder, don’t trust dweebs on the internet. Do the tests yourself, or at least double check my data.

64 sample buffer - NO Minimize Additional I/O Latency

Pro Tools - 64 Sample Buffer - No Minimize I/O Latency (Video)

64 sample buffer

  • Reported Latency - N/A

64 sample buffer - Minimize Additional I/O Latency

Pro Tools - 64 Sample Buffer - Minimize I/O Latency (Video)

256 sample buffer

  • Reported Latency - N/A

256 sample buffer - NO Minimize Additional I/O Latency

Pro Tools - 256 Sample Buffer - No Minimize I/O Latency (Video)

256 sample buffer - Minimize Additional I/O Latency

Pro Tools - 256 Sample Buffer - Minimize I/O Latency (Video)

1024 sample buffer

  • Reported Latency - N/A

1024 sample buffer - NO Minimize Additional I/O Latency

Pro Tools - 20489 Sample Buffer - No Minimize I/O Latency (Video)

1024 sample buffer - Minimize Additional I/O Latency

Pro Tools - 1024 Sample Buffer - Minimize I/O Latency (Video)

Data

Here is a csv of all the data, including the config files used to plot it using deltafinder.

Pro Tools data

Conclusion

  • Pro Tools exhibits MIDI->Audio playback Jitter. It appears to be approximately 1 buffer’s worth of jitter.
  • “Minimize Additional I/O Latency” appears to reduce latency by 1 buffer. More tests would be required to find the extents of the jitter to confirm the total latency reduction.
    • I can’t automate these tests and do 100s of them with the equipment that I have (yet?). 3-5 tests is my max.

Meta

This post took:

  • 5 hours to change various settings, do 3 tests, graph, and see if the setting affected the output.
  • 1 hours to capture signals and graph them.
  • 2 hours to write the article.
  • 1 hour to track down an error with a measurement.