clintrubber
Well-known member
Hi,
I've been thinking a bit about adding tap-tempo functionality
to some old analog effects like S/H-controlled filters, amplitude-modulation-FX etc.
So I'm looking for/want to make an add-on circuit that can synchronize an
LFO to a footswitch-tapped tempo.
I figure that the tap-button we see on digital-FX-boxes will be a simple
effortless requirement; I guess the existing DSP just counts how long
between pulses.
But if one would want to make a stand-alone add-on to an existing circuit,
what would be the best way ?
Have some thoughts about how to realize it,
but so far the circuits seem a bit overly complex.
Some thinking out loud:
* Counters: hardware-realization with off the shelf gates will
likely be too complex; (but I have no experience with a PIC/...-realizations)
* 'Analog' realizations with voltage controlled LFO's may suffer from drift.
Let's see what a stability-requirement could be. Let's just assume a 3BPM-drift over a
180BPM three minute song is tolerable (without intermediate tapping to correct).
Uhh, that's an allowed drift of some figure, but how stable are the musicians
themselves actually ? Without click, likely they won't be much better than
that 3BPM-shift.
Actually a bit hard to define a requirement for the taptempo-circuit here,
putting this one aside for now.
Apart from people adding footswitches to existing circuits,
I haven't seen any DIY-taptempo circuits so far.
Anyone ? (Suggestions for asking this somewhere else also appreciated.)
Thanks !
Peter
I've been thinking a bit about adding tap-tempo functionality
to some old analog effects like S/H-controlled filters, amplitude-modulation-FX etc.
So I'm looking for/want to make an add-on circuit that can synchronize an
LFO to a footswitch-tapped tempo.
I figure that the tap-button we see on digital-FX-boxes will be a simple
effortless requirement; I guess the existing DSP just counts how long
between pulses.
But if one would want to make a stand-alone add-on to an existing circuit,
what would be the best way ?
Have some thoughts about how to realize it,
but so far the circuits seem a bit overly complex.
Some thinking out loud:
* Counters: hardware-realization with off the shelf gates will
likely be too complex; (but I have no experience with a PIC/...-realizations)
* 'Analog' realizations with voltage controlled LFO's may suffer from drift.
Let's see what a stability-requirement could be. Let's just assume a 3BPM-drift over a
180BPM three minute song is tolerable (without intermediate tapping to correct).
Uhh, that's an allowed drift of some figure, but how stable are the musicians
themselves actually ? Without click, likely they won't be much better than
that 3BPM-shift.
Actually a bit hard to define a requirement for the taptempo-circuit here,
putting this one aside for now.
Apart from people adding footswitches to existing circuits,
I haven't seen any DIY-taptempo circuits so far.
Anyone ? (Suggestions for asking this somewhere else also appreciated.)
Thanks !
Peter