[sdiy] Tap Tempo

[harrybissell]

It would be easy to use a high speed counter. Start the counter on the
first tap,
latch the value with the second tap, then preset that value into another

counter and let that one loop. If you made the master clock run at some
integral
multiple of the tap timing clock, you could get N-pulses per note as
well.

It would be quite a bit of logic but is not hard to do. Yes... a micro
would be a
way more effective way to go. A single PIC could handle it all, to
arbitrary precision.

I just use a piezo pad to trigger the drum sound directly... tap tempo
is not an issue.

H^) harry

D A F wrote:

> This might be a dumb idea but could it be done with a phase-locked
> loop of some kind?  I dont recall them being used to track frequencies
> in the single digit hertz range but could it be done? Dave
>
>      ----- Original Message -----
>      From: Amos
>      To: Tim Parkhurst
>      Cc: D A F ; synth-diy at dropmix.xs4all.nl
>      Sent: Thursday, December 29, 2005 2:48 PM
>      Subject: Re: [sdiy] Tap Tempo
>       A simple tap-tempo program to feed to a micro is along the
>      lines of:
>
>      begin program on first tap event -
>      measure time until second tap event
>      measure time between second and third tap events
>      average the two measured intervals
>      set the new tempo to be one beat = the average interval over
>      the three taps.
>      (and reset the counter so that the next tap initiates the
>      cycle again)
>
>      so a-one, a-two, a-one two three and by the downbeat you are
>      groovin' in tempo.
>
>      This is how tap tempo in the moog MuRF is implemented... In
>      practice I find it works a bit better than the simpler
>      method of taking only one interval between any two taps -
>      which is less accurate (or rather requires the user to be
>      more accurate).
>       On 12/29/05, Tim Parkhurst <tim.parkhurst at gmail.com>
>      wrote:
>
>           This did come up a while ago (six months or so, I
>           think), and the general consensus was that a
>           microprocessor-based solution would be simpler and
>           much more accurate. Well, simpler if you know how
>           to program a micro. I think a discrete digital
>           solution ( i.e. not involving a micro) was also
>           proposed, but this would probably end up using a
>           lot more hardware than a processor driven
>           solution. Might be worth checking the
>           archives. And no, not really off-topic at all.
>           :)  Tim (as simple as it gets) Servo--
>           "Imagination is more important than knowledge." -
>           Albert Einstein
>
>           ***************************On 12/29/05, D A F
>           <polaris30 at ncx.com> wrote:
>
>                Hi all,
>
>                sorry if this might be a little
>                off-topic, but here goes:
>
>                I was wondering if anyone knows how the
>                more recent effects with "tap tempo"
>                (where the period of an LFO is synched
>                automatically with the taps from a
>                foot switch) is implemented?  Does this
>                have to be done with a processor of
>                some kind, or could it be done in
>                analog?
>
>                thanks,
>
>                Dave
>
>
>
>
>