Resurrecting an old question. Did anyone ever find a good solution to syncing two taptation controllers (parallel delays), so that switching tempo selection doesn't throw them off? Maybe having to re-tap after any tempo selection changes is not that big a deal...
So I've been testing this a bit. One thing I noticed was that when tapping one taptation circuit I could sometimes trigger the other taptation to resync to the Time pot. I put each taptation onto its own 5V regulator and that cleaned up whatever voltage drop that was triggering the other circuit. The final circuit design, adding in the PT2399 and modulation circuits, will need to be pretty clean for power and ground for consistent operation.
For syncing, it's clear there's no way with the current code to do a continuous cross-sync. When the taptation receives a new tap input, it looks like it affects the tempo clock right away and starts its new tempo once the input time window is done. So a continuous or periodic sync signal would be disruptive. Also, changing and resetting the tempo scale or double time causes the tempo to go out of phase, depending on exactly when you toggle the switches... but the tempo frequency is maintained. I found that using a single tap input to both taptations reliably gave a syncrhonized response, assuming you don't switch the tempo scale or double time.
I'm okay with this... just means that I'll have to retap anytime I change the tempo scale or double time. Here's what I'd like to do next:
1. A frequency/phase comparator so that I can compare the two taptation tempo outputs and light an LED when they are In Sync / In Phase
(I think there might be a number of ways to do this)
2. A Scaled Tempo period digital display in msec.
(I'm wondering if there is a prebuilt LCD circuit for this that would be easy to hook up)
(Update: I see lots of frequency counter display kits out there, but looks like I'd have to program my own PIC to get a Time Period display in msec.)
Any ideas or suggestions on these two ideas?
I'm also planning to compare the Echobase vs Taptation modulation, and decide if I want both (switchable, or one of each on the two delay circuits). I'm also planning to play with series vs parallel for the polyrythmic settings. If I like both, not sure if I'll use a toggle switch or switching jacks to give both options.
Here's what my breadboard looks like right now: