Build Your Own Superfast Polyphonic Octaver Pedal with DT-FOG Module

Introduction to DT-FOG Module Unlike other polyphonic octaver pedals those have significant latency, DT-FOG module produce octave and sub-octave with almost imperceptible latency. The DT-FOG module processes transient and non-transient signal components separately. This separation enable the transient processor to have superfast latency as low as 1/100 seconds (10 milliseconds), and the non-transient processor to have a good frequency resolution […]

Read more

DIY Guitar Vocoder Pedal Using BWE-VO3 Module and GBPM-2 PCB

WARNING! As of August 30th 2023, BWE-VO3 module is discontinued (obsolete), replaced by DT-VO4 vocoder module. Refer to the following documents to build DT-VO4 Vocoder: DT-VO4 Vocoder Module User Manual DT-VO4 Application Note (BUILDING GUITAR VOCODER PEDAL USING DT-VO4 MODULE AND BGPM-2 PCB) Introduction BWE-VO3 is a vocoder effect module designed for guitar effect pedal application, based on digital simulation […]

Read more

ESP32 I2S-PDM Interface for Digital Guitar Pedal Application

The PDM (pulse-density modulation) has been widely used in the current technology of audio signal conversion (from analog to digital) because its simplicity while achieving high quality conversion. This technology is widely used in digital microphone, and it is basically a sigma delta modulator circuit which is used in many modern audio codec chip as well. It is an interesting […]

Read more

ESP32-A1S Guitar Multi-Effect Engine with Microphone and MIDI I/O

Since the release of ESP32 by Espressif, many application-specific modules based on this chip are produced. For example, Ai-Thinker produce image processing module with artificial intelligence support for image recognition. In the audio processing area, one interesting product by Ai-Thinker is the ESP32-A1S module. Because of the integrated AC101 codec inside, this module enable very compact and low cost solution […]

Read more

DIY Reverb Pedal Circuit: Spring-Hall Reverb with PT2399 IC

Introduction to Reverberation Before getting into the design of DIY reverb pedal circuit, lets see the concept of reverberation first. Real reverberation happens in a performance chamber when the walls and every object inside reflects the sound back and forth. As the sound bounces back and forth in three dimensional space, the reflections creates more and more complex pattern. The […]

Read more

Linear Interpolation Extension Employing Three-Gradient

Speed and Memory Size Optimization When developing digital signal processor for Deepstomp, we employs a cheap 32-bit processor without floating point unit. Consequently, we have to optimize all computation in fix point math. The most important effect, especially for electric guitar, is distortion effect. It is simulated using sigmoid or sigmoid-like functions such arctan, tanh, or some others. Those functions […]

Read more

DIY Multi-Effect Pedal Platform is Now Low-Cost!

DIY Multi-Effect Pedal and Today’s Advanced Electronics Digital DIY multi-effect pedal is an expensive things in the past, but the advance of today’s digital electronics brings new hopes for many things. Because now there are many choices for low cost and high performance DSP microcontrollers, now I think we can implement a DIY multi-effect pedal with much lower cost than […]

Read more

DIY Digital Effect Pedal Platform Review: The Top 9

9 DIY Digital Effect Pedal Platform List To start researching on DIY (do-it-yourself) digital  effect pedal for the next project, let’s see the list first. Take a look at some popular platforms to compare their specifications and prices, here are some: UNO – Electrosmash’s pedalSHIELD UNO MEGA – Electrosmash’s pedalSHIELD MEGA DUE – Electrosmash’s pedalSHIELD DUE Electrosmash’s Pedal Pi Openmusiclabs’s […]

Read more

Automatic Wah/Quack Effect Circuit with Attack and Decay Control

To get various characteristic of an auto wah/quack effect, we need a flexible control of  the envelope detection characteristic. Some playing styles need slow attack but fast decay,  but some others don’t. Employing the envelope detector circuit presented in our previous article [Ref 1], but with some modification to make it single supply operation. Here we present the improvement of […]

Read more

Fold-Back Distortion: Producing “Phew” Effect Using Software and Hardware (Analog Electronic Circuit)

Introduction: What is Fold-Back Distortion? I was introduced to a term of  “fold-back distortion” in the past by an article from an old book which I forget what the title is, but the book contains schematic diagrams of many circuits collected from old publication of Elektor magazine (www.elektor.com). The article presents the circuit’s schematic diagram and how it works. I […]

Read more

Symmetric Distortion Using Clipper Diodes for Guitar Effect

Introduction While almost every audio equipments  pay whatever it cost to minimize distortion, this kind of device does the opposite: distortion effect for electric guitar. Many methods have been implemented in producing a distorted signal from electric guitar pick-up, such as over-driven vacuum tube, solid-state (transistor), or diode clipper. The simplest form is passive diode clipper, which is implemented as […]

Read more