Set timeline to start at 0 rather than negative number

Audacity 3.2.4arm on mac mini m2.
I clean installed rather than migrated from my old mini running Big Sur.

Now the timeline starts in negativeland. Either -1 or -15 seconds depending on zoom.

Play head is not pinned.

How do I set timeline to start at zero?

I’ve searched the forums and the internet at large, read the timeline section of the manual, and come up empty. sorry if this is obvious, don’t mean to waste folks’ time.

TIA, Chris

In preferences > Track Behavior there’s a setting called “Enable scrolling left of zero”. Disable that.

If it’s already disabled, it may be that you just see the timeline extending into negative time without you actually being able to reach back there.

If you think it’s something else, please attach a screenshot

Thank you very much for your help.

“Enable scrolling left of zero” is not checked in prefs.

I’ve set zoom to 15 secs scale.

Screenshots below showing that when I click in the track at around 15 seconds in, then hit ‘shift-j’ to select back to 0, roughly 15 seconds in negativeland are selected too.

Hitting delete removes about 30 seconds of the track.

Screenshot 2023-02-08 at 10.29.00 AM.png
Screenshot 2023-02-08 at 10.27.53 AM.png
Screenshot 2023-02-08 at 10.27.43 AM.png

Windows guy here. I see no one has replied to your recent post. Does this happen when you start a new project ? Can you provide steps to reproduce the issue?

I don’t get a similar selection in negative time:

  1. Generate a 3 minute chirp
  2. set cursor at 15 seconds
  3. Shift+J
  4. Observe: selection is from 0 to 15 seconds
    What I do observe from your posted image is that in the top track you have audio in negative time - see the little arrows at the left of the track.

    So my next test
  5. Generate a 3 minute chirp
  6. drag the clip leftwards so that 15 secs is before T=0
  7. st the cursor at T=15
  8. Shift + J
  1. Observe: selection extends over negative time -15 to +15
    This I believe is correct behavior. The keyboard prefs for Shift+J says of that shortcut “Region Track start to cursor”
    which is the command Select> Region>Region Track start to cursor

And the Manual says:

Track Start to Cursor Shift + J
Selects a region in the selected track(s) from the start of the track to the cursor position (or extends the current selection so that it starts from the start of the track).

And since the track now starts at T=-15secs the observed behavior is correct and expected. I would also expect the deletion to work on the selected part of the track that is in negative time.

The big question is just why you have audio in negative time?

As what I observe of your behavior is correct and expected too.


Basically audio in negative time is a real bane and really unnecessary I always think - I started a discussion thread about this on Muse’s GitHub a few weeks afo:

Why do we have negative time in Audacity - do we need it? #4188


I have added an advice div in the manual (alpha manual for the upcoming 3.3.0) to warn about this:

Thanks Peter et al.,

I confirmed that this seems to be an issue with a particular .aup3 file having information in negative time somehow.

See screenshot showing another work file, on which I clicked around 5 seconds in, hit shift-j, and have selected only positive time.

Not sure how I got info into negative time, gotta hope I don’t again.
Screenshot 2023-02-12 at 11.07.09 AM.png

Figured out a solution, posting in case anyone else gets in this situation.

I simply sync-locked all tracks and used time shift to move all the content that was below zero seconds to the right, so that the actual start of the data was at zero.

All good!

Then I trimmed the first 15 secs off the start like I needed to and was on my way.

Thanks all!