How Tap Tempo works

[silverhead]

One of the bugs in v2.90 was Tap Tempo. I believe it's now fixed in v2.91 but I never really noticed the bug so can't confirm that it's been fixed.

 

However, the discussion at the time left me with an unresolved question: How many 'taps' in sequence are considered in the calculation of the tempo that is then applied to time-based FX? Clearly if you only tap twice that defines a specific tempo based on the one interval between the two taps. But what if you tap 3 times? Does it take an average of the two intervals or only use the final interval? And if it takes an average of a sequence of taps, what is the maximum number of taps/intervals it uses to calculate the final tempo?

 

So I did some further testing. My initial (poor) testing told me at the time that only the final two taps were considered and I stated that wrongly in one of my posts. Time to correct myself. Further testing shows that Helix takes an average of up to 10 (yes, 10) taps! That surprised me.

 

To test for yourself use a metronome at 60bpm.

 

Test#1: Tap the full beat once. This requires two taps. (counting 1...2) Observe that the tempo is set to 60bpm (more or less depending on the accuracy your tap timing).

Test #2: Tap the full beat once followed by two half-beat taps (1...2.&.3). Notice that the tempo calculated up to any point is displayed immediately after each tap. Observe that the final tempo in this test is set to 90bpm, the average of the three intervals created by the 4 taps. The final tempo is not 120bpm which is the duration of the last two taps that define the third and final interval. Repeat this test reversing the intervals. (1.&.2...3). The average is still 90bpm.

Test#3 and onward: Continue tapping the half-beat after the first full beat for multiple different trials (1...2.&.3.&.4), then (1...2.&.3.&.4.&.5). In each trial observe that the final tempo increases following each tap until you have completed at least 10 taps, after which the calculated tempo finally ignores the first long tap and settles at 120bpm (again depending on the accuracy of your tapping).

 

So what does this mean? For those of us who use Tap Tempo in a live setting we should tap at least 10 times to get the best accuracy. In particular, DON'T make an erratic first few taps and then stop after you've tapped accurately 3 or 4 times. Those first few badly timed ones will count and throw your time-based FX off tempo!

 

And yes, I am a bit OCD. This was just bugging me!

[Lone_Poor_Boy]

37 minutes ago, silverhead said:

And yes, I am a bit OCD. This was just bugging me!

 

I was smiling as I read through this and you summarized why at the end!  I can relate. That is cool though and makes sense. Gives you a chance to get it right through averaging. That can certainly help someone like me who can get something like this wrong when only doing two, and would start over.

[SaschaFranck]

Hey, many thanks for your experiment, silverhead!

Know what? As we discussed this in the bug thread yesterday, I wanted to do some more elaborated tests just today, as the 2.9 issues seem to be fixed (in fact, they are). I was even planning to start a new thread with the results - but to my amazement, you've beat me at it, so cheers!

And it's pretty interesting that you can actually perform so many taps - that should result in pretty good averaged values for live playing (in case you find a spot to tap so often, rather looking like a stork or so).

 

Now, the only relevant question remaining might be: In case you did some badly timed taps at first and don't want to bother with 10 more, how long does it take the tap tempo function to forget these first taps in case you don't touch the switch at all anymore? Yeah, pretty much a rather academic question, but in case of very slow tempos, it might be quicker to stop tapping (in case you were off) and start out fresh instead of proceeding with 10 more taps.

[silverhead]

1 hour ago, SaschaFranck said:

..... In case you did some badly timed taps at first and don't want to bother with 10 more, how long does it take the tap tempo function to forget these first taps in case you don't touch the switch at all anymore? ...

 2 seconds according to my observations.

[silverhead]

1 hour ago, Lone_Poor_Boy said:

 

I was smiling as I read through this and you summarized why at the end!  I can relate. ....

.
Actually I call myself CDO now. I can’t  stand that they’re not alphabetical! ;-)

[SaschaFranck]

12 minutes ago, silverhead said:

 2 seconds according to my observations.

 

Ah, ok, thanks again. So it might make sense to stop tapping at all and restart when the first taps were off.

[silverhead]

Yes. I think if your first few taps are not right you’re best to wait at least 2 seconds and start over. Then try to do three or four accurate taps. You don’t really need 10 as long as you’re paying attention at the start.

[HonestOpinion]

3 hours ago, silverhead said:

One of the bugs in v2.90 was Tap Tempo. I believe it's now fixed in v2.91 but I never really noticed the bug so can't confirm that it's been fixed.

 

However, the discussion at the time left me with an unresolved question: How many 'taps' in sequence are considered in the calculation of the tempo that is then applied to time-based FX? Clearly if you only tap twice that defines a specific tempo based on the one interval between the two taps. But what if you tap 3 times? Does it take an average of the two intervals or only use the final interval? And if it takes an average of a sequence of taps, what is the maximum number of taps/intervals it uses to calculate the final tempo?

 

So I did some further testing. My initial (poor) testing told me at the time that only the final two taps were considered and I stated that wrongly in one of my posts. Time to correct myself. Further testing shows that Helix takes an average of up to 10 (yes, 10) taps! That surprised me.

 

To test for yourself use a metronome at 60bpm.

 

Test#1: Tap the full beat once. This requires two taps. (counting 1...2) Observe that the tempo is set to 60bpm (more or less depending on the accuracy your tap timing).

Test #2: Tap the full beat once followed by two half-beat taps (1...2.&.3). Notice that the tempo calculated up to any point is displayed immediately after each tap. Observe that the final tempo in this test is set to 90bpm, the average of the three intervals created by the 4 taps. The final tempo is not 120bpm which is the duration of the last two taps that define the third and final interval. Repeat this test reversing the intervals. (1.&.2...3). The average is still 90bpm.

Test#3 and onward: Continue tapping the half-beat after the first full beat for multiple different trials (1...2.&.3.&.4), then (1...2.&.3.&.4.&.5). In each trial observe that the final tempo increases following each tap until you have completed at least 10 taps, after which the calculated tempo finally ignores the first long tap and settles at 120bpm (again depending on the accuracy of your tapping).

 

So what does this mean? For those of us who use Tap Tempo in a live setting we should tap at least 10 times to get the best accuracy. In particular, DON'T make an erratic first few taps and then stop after you've tapped accurately 3 or 4 times. Those first few badly timed ones will count and throw your time-based FX off tempo!

 

And yes, I am a bit OCD. This was just bugging me!

 

Thanks for running this experiment Silverhead. Love the results and how many taps the Helix is capable of averaging. That is great design! Don't think I will be tapping ten times on any regular basis but good to know it will average my first few taps.

[HonestOpinion]

1 hour ago, silverhead said:

.
Actually I call myself CDO now. I can’t  stand that they’re not alphabetical! ;-)

 

Already stole this, gave my wife a good laugh yesterday.  :-)

[SaschaFranck]

1 hour ago, silverhead said:

Yes. I think if your first few taps are not right you’re best to wait at least 2 seconds and start over. Then try to do three or four accurate taps. You don’t really need 10 as long as you’re paying attention at the start.

 

I'm actually quite used to just tapping twice, mainly because most devices don't calculate average values (ok, the Boss things I used for a long time do) but also because I hate it in a live context. I actually don't exactly know why because I'm tapping quarters almost all the time, but it seems to be really distracting in case you have to hit a switch as well.