Change TEMPO effect with a visual interfase

The Change Tempo effect has three ways to set the amount of change to aply to the selection: “Percent change”, “Beats per minute (from, to)” and Leght in seconds (from, to).
My proposal is to add a fourth way to set the change, graphically extending or contracting the selection chosen as “from” on the timeline.

OK, but exactly how would that work ?

Th idea is to have the posibility to see in the time line the new extension of the selected audio.
I imagine two alternatives:
a) With a second step when you extend or contract the selection in the time line and the Lenght in seconds “to” actualices automaticaly, or
b) Draging the “Percent change” control while the change is displayed on the timeline

I don’t know if all of this is possible.
I have been using Audacity since the beginning of the Covid 19 pandemic, to mix voices of an amateur choir, which were recorded separately, in the singers’ house, and I want to correct small imbalances. Normally, there are many minor imbalances and if you could visualize the results without the need for calculations of times or percentages, the process would be simpler and faster.

In the timeline it is possible to distinguish the articulation that each singer performs and I seek to be able to visually align those aticulations.

Thanks for clarifying your use case. :smiley:

Currently, I am not sure you need that calculator. Before you run change tempo, Do this:

  1. Select > Region > Store Selection (this holds your current selection)
  2. Select a target region (where you expect the selection to expand to - this is the thing I think you were talking about)
  3. Note the length of your target selection in the Selection Toolbar (Start and Length of Selection) near the bottom of the screen
  4. Select > Region > Retrieve Selection (this recovers the current selection)
  5. Effect > Change Tempo
  6. Specify the length that you noted at 3.

You probably don’t even need to store and retrieve your selection. :smiley:

I hope this helps. :smiley:

Thank you very much for your answer.

What you explain is very similar to what I do, although I did not use the save and retrive selection options: I retrieved the first selection manually in the selection toolbar.
I am going to use the Save and Retrive selection options via keyboard shortcuts.

It is not the way I imagined, but your advice has been very useful.

Thanks a lot :smiley: