sah~, !-~, and selector~ ought to do the trick.

Thanks for the replies.

I'm just using the phasor~ for loop playback. I made another attempt using pong~, but there's still discontinuities and it doesn't really work. Basically, my approach is to establish a forward signal and an inverted reverse signal and then to add an offset at the moment the direction is changed. At that moment the signals should have the same value and a selector~ switches to the other signal. I know there is a problem in that when the direction is changed, the current offset needs to be taken into account which it is not in this patch. I wasn't able to implement that without creating a feedback loop with sah~, and I wanted to avoid using send~/receive~. I'm sure the solution is simple and straight forward, so maybe I'm totally on the wrong track.

Here's the current patch:

Sorry, copied inline:

you need to make your own phasor (using +=~), so you don't have to deal with the idiosyncrasies of the existing one, then it's really quite simple:

Thanks a lot, Terry. Exactly the elegant solution I was hoping existed. Still feeling my way around the signal domain...

~ s