Precise timings

Audacity Help Forum Windows
1

I’m using 2.4.2 on a windows 10 machine. I am using it for acoustic experiments, looking at waveforms. I would like to select a section of a waveform and get an accurate time for the interval, but the selection toolbar only goes down to milliseconds. Seems I should get fractions of a millisecond down to the sample rate. I guess I could set it to sample and then do a multiply, but it’s pretty cumbersome to have a spreadsheet open and do a bunch of cuts and pastes to do a simple calculation that I would think would be on board audacity. So, is it possible to get a time interval measurement that reflects the sampling rate down to fractions of a millisecond? If I’m using a 44,000 sampling rate, I should get accuracy down to ~0.025 msec. Thanks

2

It goes down to “samples”. By default that’s 1/44100th second, though you could resample up to 100,000 Hz (or even 1,000,000 Hz) for easier numbers.

3

You can reset the format for the Selection Toolbar (and the Time Toolbar) - just click on their little-black-downward-pointing- triangls and you will get a dropdown list of formats you can select from.

Please see: https://manual.audacityteam.org/man/selection_toolbar.html

When I was converting my LPs and used the Repair effect a lot I always had mine set to hh:mm:ss + samples and the Selection toolbar set to Start and Length of Selection - for precise selections to repair.

WC

4

Thanks for the help, but neither reply is workable. I am interested in fractions of a millisecond. The timings using the drop down box only go down to full milliseconds. As for the suggestion to resample at a different rate, there are only discrete rates that can be sampled. At least, I can’t see a way to sample at say 50khz or 100khz. The choices are 48khz or 96khz. So again I am stuck typing the interval into a spreadsheet and doing a manual conversion if I want some accuracy. Not impossible, but a pain. Particularly, when I have all this computer power sitting in front of me and I have to manually do multiplies!

5

Try typing into the “Project Rate” box in the lower left corner of the main Audacity window.
See: Selection Toolbar - Audacity Manual

6

Thanks! That seems to work. In fact, if I change the rate after recording, Audacity appears to interpolate to the requested sample rate, so I can still do the measurement. Thanks again.