Sunday, 3 April 2011
New Tap Looper Design
I'm continuing to explore the tap looper concept and have come up with this schematic for a variable length, tap programmable looper (click the above image to open it in a larger window). The great thing about being able to vary the length of the register is that you can then create sequences in alternate time signatures as well as 4/4. This variable shift register IC the MC14557 can be programmed to create any register length up to 64 bits..in the video below I am using 48 bits to create a 2 bar 3/4 time signature using 8 bits per 1/4 note resolution. I am pleased with this design (mostly as really it is the first thing I have designed from scratch based off the info in the datasheet) however it has the same shortcoming as the 4031 based tap looper- that it only maintains resolution at faster tempo's. I plan to experiment with cascading 2 of these registers, doubling the length of any given loop so that I could create 4 bar sequences at higher tempos and 2 bar sequences at lower tempos whilst still maintaining enough resolution.
Feel free to use this schematic however you like but give me a credit if you can :)