by Ryan » Wed Aug 13, 2014 9:18 pm
Guys, buddies, pals.. this is a project that is finished, it's a spectrum analyzer. It's a box you put by your stereo or your computer desk or your band room or pedal board.. it reacts to the sound input and you enjoy the moving lights along with your music. It was really hard to make, tons to learn and do, and it's fulfilled, it's a completed and totally awesome spectrum analyzer.
Please stop throwing suggestions at it, it's done and it's happy. It's not going to be put inside another box to do something else and the circuit does not output audio, it outputs information at a very fast rate, faster than your eyes can see, it's purely a visual display. And it owns at that, it's an awesome spectrum analyzer and there isn't even anything like it available.
I get that you want some kind of multi-frequency band audio effect so in the hopes that you will leave my spectrum analyzer alone I'll pseudo-design you something and you can take it and run with it.
You could accomplish what you want with a handful of band pass filters, only need half a dual op amp per filter. Buffer in the signal and split it out to 7 or however many bandpass filters you want. Crunch the numbers to tune each one to a good guitar frequency, maybe like 100Hz, 250Hz, 500Hz, 1000Hz, 2000Hz, 3000Hz, 5000Hz, or use musical values that correlate to notes maybe that'd be better. So now you've got your bandpass outputs each at a frequency, take those outputs and do whatever you like with them.. send each output to a fuzz stage, a delay stage, a mute stage.. and then mix them back in at the output, add a buffered clean blend, you could have a whole line of pedals that worked off that premise. You could also drive an LED with each output, hook an LDR to the LED and now you have a varying resistance that can be a circuit element for you.
Maybe an even easier way to accomplish a multi-frequency dependent effect would be to use a state variable filter. Two dual opamps and you get 4 outputs, a low pass, band pass, notch, and high pass.. you could then take those outputs and feed them to different circuit blocks for fuzz or whatever, mix them back at the output and clean blend, boosh.
I agree, cool effects to be had there for sure! But they don't involve my spectrum analyzer! *runs to bedroom with spectrum analyzer and slams door*