I found a FET that says it will do up to 10KHz with minimal distortion to a sine wave. I want an octave up on bass I can put a slight delay on for tic tac sound. For all you non classic C&W guys tic tac was a guy usually with an old Danelectro Baritone echoing the bass line kind of like Wilie Nelson sings. (off meter delayed) I am thinking a limiter on the delay to cut off any sustain on the note for that sharp octave "tac" (or is a tic?) up echo. Decay will be adjustable as will the delay time. I am just going BBD for delay, and have a split out or a mixed out. Any ideas why it wont work? The Fet has a pot to keep is adjusted to keep self oscillation from occurring. The circuit looks too simple. If it needs to be tank tuned I am screwed, but the 10KHz cut off is definitely audio, or VLF for submarine radios.