Interesting analog delay schemo

[Dragonfly]

Have any of you guys built this one ? Its geared toward synths, but could be cool for guitar use with a few tweaks.

[Mark Hammer]

More in slapback territory, given that it's a 3007.  I find the BBD biasing a little odd.  More like a little absent, actually.

You will note the use of a pair of fixed phase-shift stages (IC2C/2D) to generate a second "channel".  You will also note that the regeneration path ("duration") actually passes through LESS lowpass filtering than the original input signal does.