Pro Tools LE™ Latency Charts

For Digi 002® and 002 Rack™

tracking latencies:
how I ran the tests

These are the steps I followed to test for tracking latencies.

  1. Plugged an electric guitar directly into 1/4" input #1
  2. Set up two audio tracks:
    • A. Input: Analog 1, Output: 1&2, panned hard left
    • B. Input: Analog 5, Output: an unused bus
  3. Patched a 1/4 cable from monitor out Left to Analog input 5, set to +4 dBU
  4. Cranked up Monitor Level all the way
  5. Armed both tracks, got a level, made sure both tracks had the same level. The converters are low-fi enough that identical levels are not possible, but I got them as close as possible, which was +/- 0.2 dB with the electric guitar.
  6. Entered Low Latency Mode, recorded a few seconds of music.
  7. Exited LLM, set buffer to lowest setting, recorded a few seconds of music
  8. Set buffer to next highest, recorded a few seconds, and so on until highest buffer setting was reached.
  9. Changed track B output to 1&2, panned both tracks center.
  10. Placed a TimeAdjuster-Long plug-in on track A, and engaged invert (a.k.a. "phase") button.
  11. Looped each section of guitar music one at a time, finding the null point (number of samples delay where maximum signal cancellation was achieved), and entering the number of samples from the TA plug into a spreadsheet.
  12. Looped each section again, this time entering the corresponding number from the spreadsheet into the TA plug, and verifying that it was the correct null setting for that mode/buffer setting.
  13. Repeated all above for each sample rate.
  14. Had spreadsheet calculate ms and length figures:
    • ms: divide latency samples field by sample rate/1000.
    • distance: multiply ms field by 1.13 and round to whole number for feet, round down difference and multiply by 12 for inches.

Back to Tracking latencies

by David J. Finnamore
DUC ID: daeron80
Written: April 2006
Copyright © 2006, all rights reserved