Tap to slower tempo non functional

Bug reports
1

Summary: Tapping tempo to one slower than the current tempo doesn’t work. Tapping to a faster tempo works fine.

Submit Date: 2023-06-10
Reporter: Rob Voisey

Platform: Mac Mini M2
Operating System Version: 13.4
Details of laser DACs connected (number, type, connection method): 4 x Etherdream 2, Ethernet

Description

Using Tempo Tap to decrease the current tempo does not work. The tempo changes a little around
the current rate.

Steps to reproduce

Set tempo to 100bpm using encoder or text entry
Press Tap Tempo repeatedly at approx 140bpm

  • The tempo increases as expected

Press Tap Tempo at a slower rate, say approx 70bpm

  • The tempo fluctuates with each press but remains around 140bpm

Expected result

Tapping a lower bpm should adjust the tempo just as tapping a higher bpm does.

Actual result

Can’t set the lower tempo.

Screenshot

If this can’t be reproduced I’ll make a video on request.

Notes

Behaviour seems the same between TAP button in the UI and TAP TEMPO on APC40.

2

The tap tempo system is “smart” enough to know if you missed a beat, so if you exactly halve the tempo it’ll just think you’re hitting every other beat. I realise that this is not ideal in your case! But in general it’s better than most systems that get erratic if you miss a single beat.

I think I could put in a condition that checks if you repeatedly miss every other beat but for now I would use the 1/2 button to exactly halve the tempo.

3

UPDATE: I tried several transitions with a metronome. It’s fine for all realistic cases, disregard the bug!

Thanks for the explanation. It seems to affect more realistic changes than my repro case. If I’m at 180bpm I can’t get to 140bpm using the tap button, and that’s a very realistic transition at many gigs. It’s not a showstopper, I’ll hit /2 and then tap it back up, or ride the tempo fader, but nothing else I have works that way. Could missed beat detection be optional in future? I don’t know why I would miss a beat when tapping tempo. Ta!

4

Ah interesting. I will make sure to do some more testing of the system. The original code for tap tempo was written during my first show while I was waiting for Fatboy slim to start so I’m surprised it works as well as it does :sweat_smile:

Thanks so much for the comprehensive report.

1 Like
5

I updated my comment. It’s fine. Only pathological cases are a problem. Sorry for the false alarm!

6

No worries at all, I’m sure it’ll be worth double checking at some point anyway!