I have been going over some old Audacity recordings and have found one particular recording where the audio track doesn’t occupy the full space available (-1.0 to 1.0). It appears to be restricted within the range -0.75 to 0.75. Any idea why, and what I can do to fix this? Thanks in advance.
It looks like you enabled Envelope Tool and dragged the amplitude down. If so, Edit > Undo Envelope. If you have just opened the project and it’s like that, F2 to enable Envelope Tool, look for the envelope points (white dots) and drag the points out of the track to remove the envelope.
If necessary you can then use Effect > Amplify… and OK to make the peak of the track at 0 dB (-1/+1).