I noticed we can pitch shift an audio clip (preserving tempo/duration) …is this done destructively or in real-time? Ardour seems to make a separate copy of the file, but just asking to make sure.
How about time-stretching, is there a way to do it in real-time or non-destructively? Basically i have a kind of difficult/fast part in my song that i don’t have time to practice until i nail it perfectly. I recorded it a bit slower, and would like to speed it up by about 10% keeping the same pitch.
There is Varispeed, but it doesn’t preserve pitch, so you need to record slower, but also lower 
Unfortunately Ardour is far behind the others in this regard. I will keep repeating this over and over until it finally changes, I hope.
We are indeed far behind in this particular capability that played zero role in the creation of any music until about 2010, and has played very little role in the creation of most music since that time.
You can use the cue page for this, which will do realtime timestretching of audio (and MIDI) to fit tempo. You have to load regions into slots on the cue page and then trigger them.
We love paulstretch …
You could use the time-strech tool to do that. that can shrink the duration retaining pitch.
This should help
Thanks for the help everyone. I tried the above and other solutions (rubberband-r3) with mixed results, and finally ended up re-recording it at the correct tempo.
Results would have been acceptable, but there were some artifacts with inverted fifths (aka fourths) in the lower range. Basically the low note (inverted fifth, let’s say low G) ended up softer, and the upper note (root, let’s say C) was masking it completely - sounded almost like single notes through overdrive/distortion.