Recent content by Steve Schulteis

If the ATtiny is working for you, I'd say stick with it. It will probably give you a more compact circuit. If you do investigate more, you'll probably want two 555 timers (conveniently available as a single 556 chip) - one to trigger the start of the pulse, and the second to trigger its end. I...

I'm proposing the 555 as an alternative to the ATtiny for generating the startup pulse as in the linked article. The amount of modification would be the same. The main advantage would be avoiding the need for firmware, for anyone who lacks the tools to flash a microcontroller.

I'ma little late to the party, but just to throw out another option, this is exactly the sort of thing a 555 timer is good for. No code required, but maybe a little more circuit work.

Here are a few ideas for ways to reduce the processing power required by the poly octave code: Remove the "down2" octave from BandShifter if you can live without it. Don't forget to also drop its sign calculation that happens in the update_down1 function. Reduce the number of analysis filters...

If you're ok with being limited to single notes (no chords), you probably want one of the variations on the "overlap-add" (OLA) algorithm. The time domain portions of each of these videos give an overview of how it works, and they link to example source code in their descriptions.

When the Seed is connected to your computer via USB and is running the test firmware, it should show up as a serial device, which you can read from to see the Terrarium status. The Arduino IDE has a serial device monitor that should be pretty hassle-free to use. You can program the Seed in the...

Ok, so regardless of knob position, LED 1 is off, and LED 2 is on at a fixed brightness? Is there any output over the USB serial connection? If yes, what do you see and how does it change as you operate all the knobs, switches, and stomps? If no, does that change if you remove the Seed from...

For those of you that like to monkey with code, I just (finally) pushed a new branch that generalizes the algorithm to allow arbitrary pitch shifts instead of being limited to octaves. It's not really a usable effect as-is (at least not for my purposes), but maybe it can become a part of...

I'm using the cycfi q library to do monophonic pitch detection for my synth pedal: https://forum.pedalpcb.com/threads/terrarium-synth-pedal-code-demo.22631/

You should be fine with the 1MB version. Here's the reported memory usage for my code (see How to determine your memory (RAM) needs): Memory region Used Size Region Size %age Used FLASH: 75576 B 128 KB 57.66% DTCMRAM: 0 B 128 KB...

So... there's a companion webpage for the paper, which features a few recordings and the results of feeding them through various products/algorithms. Now I've put the originals through my pedal as well for comparison - links below. All my files have been normalized but are otherwise unedited...

An impulse test shows a delay of about 4 ms, which is very close to what was reported in the paper for ERB-PS2. My measurements of the Sub 'N' Up were similar: about 4 ms. I don't have one to compare against, but the paper reported delays of 15-20 ms for the POG. But there were significant...

All the code outside of the lib directory is my own*. I'd say I followed the spirit of the paper, but I didn't end up slavishly copying every detail it specifies. I'm not aware of an existing implementation published anywhere. More information than you bargained for inbound... ERB-PS2...

I got another one for y'all. This time we're doing polyphonic octaves, like a POG or a Sub 'N' Up. Project page: https://github.com/schult/terrarium-poly-octave Firmware binary: https://github.com/schult/terrarium-poly-octave/releases/download/v1.0.0/TerrariumPolyOctave.bin Not the best...

I went ahead and adjusted the trigger range. It covers anything I'm likely to care about for my setup, but it's still a shot in the dark for guitar. Here's a temporary build if anyone wants to test it (this file will self-destruct in 7 days)...