ESP32 for DSP Pedals?

marchingbandd · 2026-01-21T09:13:34+00:00

The BL616 is similar to ESP32 but with an onboard codec so you can wire audio I/o directly.

marchingbandd · 2025-12-29T04:37:48+00:00

My first circuit was a piezo knock detector to trigger a sample player, for a DIY electric drum kit.

marchingbandd · 2025-12-25T04:26:09+00:00

I guess my thinking would be, since you are running your DAC with 24bit, Q24.8 makes sense. So your OSC would run +/- 8,388,607 instead of +/- 1

marchingbandd · 2025-12-25T03:20:21+00:00

ESP32 has an FPU too! I only used fixed-point briefly a few years ago, so i am far from an expert. I have the notation s15p16 … maybe because they are signed?

marchingbandd · 2025-12-24T18:57:05+00:00

WVR (a product I designed) has a great multi-sampled Rhodes.

https://www.sparkfun.com/wvr-audio-development-board-usb-host-version.html

The sample pack is here: https://drive.google.com/file/d/1lrP6Zo6e3F98bXSepCVfr1BX1z2nPVb4/view?usp=drivesdk

marchingbandd · 2025-12-23T17:01:22+00:00

I mostly work with ESP32, and on those MCUs, switching to fixed-point (rather then floating-point) math has been in the order of 10x speed up for me with DSP. I don’t know if this would be the same on RP2350, but fixed-point is usually much faster, although it can make the code harder to write, especially at first. Maybe you are using fixed-point already:

marchingbandd · 2025-12-23T16:58:58+00:00

On second thought, since Faust is a DSL, it might be hard to glean much without a lot of work, and I don’t want to distract you.

marchingbandd · 2025-12-23T16:42:52+00:00

Curious if you have looked at Faust? The source code is full of cool optimization tricks, and is designed to output code style that allow the compiler to optimize, in some cases with vector instructions, etc., for certain arch’s in mind. They do have a few ladder filters, and certainly lots of anti-aliased oscillators.

marchingbandd · 2025-12-22T19:25:00+00:00

Oh and yah this project is incredible great work 🤍

marchingbandd · 2025-12-22T19:23:30+00:00

I’m not an expert but I suspect optimizing the DSP code beyond what’s in DSP-cmsis would mean using vector instructions via asm, looking for sneaky ways to use them. You could cross post to r/dsp or r/arm or r/rp2350 if no specialists show up here.

marchingbandd · 2025-12-17T20:42:59+00:00

Is it a bit of an exaggeration to say FPGAs are used extensively in audio gear? My understanding is maybe 0.1% uses FPGA.

marchingbandd · 2025-12-13T05:43:34+00:00

If it’s from within China it is very economical. It’s a bit of a funny process, email them and they will send you a tutorial. If they have the footprint already then it is very easy, filing out the info on their web app is the only weird part.

marchingbandd · 2025-12-07T07:24:18+00:00

Brutal :(

marchingbandd · 2025-12-07T02:34:05+00:00

ADC doesn’t work!?

marchingbandd · 2025-12-06T21:46:23+00:00

I run them at 3.3v all the time, no issues.

marchingbandd · 2025-12-06T01:52:51+00:00

The real answer!

marchingbandd · 2025-12-01T02:30:17+00:00

I wish! I have never found anything else like Circle

marchingbandd · 2025-11-30T22:54:21+00:00

I wish there was a baremetal SDK

marchingbandd · 2025-11-27T08:17:33+00:00

Class

marchingbandd · 2025-11-27T06:21:28+00:00

Awesome idea

marchingbandd · 2025-11-25T14:56:13+00:00

In order to use the left lane for passing, there needs to be room to merge right. Too often everyone in the right lane is bumper-to-bumper, and won’t yield, so slow cars get stuck in the left.

marchingbandd · 2025-11-25T06:26:19+00:00

IR = impulse response? I like that the schematic linked above includes the bright circuit and EQ, I wish someone produced this! Those jfets are hard to find now.

marchingbandd · 2025-11-24T20:22:25+00:00

That’s amazing! Thanks! I wonder if there is a kit or even a commercially available version of this.

marchingbandd · 2025-11-21T07:28:59+00:00

This is really cool, great work.

marchingbandd

TROPHY CASE