So I'm building a musical sequencer that uses a shift register to close relays and pass the discharge pins of three 555 timers through a manual switch and potentiometer (acting as a variable resistor) to vcc. Here's somewhat what it looks like, but with only a SPST relay, and no integration of the flip-flops that will add a single bit to the register when the device is turned on.
I want the shift register to trigger all three 555 "channels" at once, so I can play chords.The only problem is, I'd need one TPST relay for each step, that's 8 per 8-bit shift register, and they're fairly expensive.
I was just wondering if there was a cheaper alternative to TPST, or three SPST, relays. Name ideas are also cool. Not sure what I want to call the thing. It's going to be modular and block-based, so I can daisy-chain more shift registers to the end to add more notes.