[posted] Jaws-fx Guitar Pedal


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JAWS-FX - Teensy 4.0 based concept art guitar pedal

This device was a part of two component birthday gift for a seasoned Jaws movie fan. The 1st component consisted of a Jaws themed guitar. My task was to come up with a guitar pedal that will fit into the whole concept.
Initial idea was to make something that plays the well know iconic music from the 1st movie. It quickly grew up to something more unique, still Jaws related sample player, but with a stereo plate reverb and a few add-ons for pleasant jamming along the music.
By that time i had already a new Teensy4.0 based guitar pedal board designed and decided to use it as the hardware base for the Jaws FX:


The board incorporates the SGTL5000 codec, input buffers, output antilaliasing analog filters, CD4053 based bypass system, MIDI i/o and separate VREGs for digital and analog parts
What i needed more is to add a analog pass through, a dry/wet mixer, relay based stereo bypass and some blinky lights to show the status (4 reverse mount RGB leds driven by PCA9685). The result was a sandwich made of 2 PCBs:


The enclosure is a Hammond 1590S, graphics are UV printed decals + airbrush + automotive clear coat.



To make the device more attractive for actually making music with it i decided to add a few things:
  • Split the music into 4 loops, switchable using the right footswitch. Short click arm the play of the next loop when the current is finished. Holding down the footswitch arm the previous loop. Each loop has a increasing level of drama. Called it "shark proximity" parameter.
  • Left footswitch acts as bypass (short click) or a quote player. There are several quotes from the movie, randomly chosen and played over the music if the left footswitch is held down.
  • Guitar path got a new allpass based stereo plate reverb. Jamming is always more pleasant using some kind of acoustic room simulation.
  • Added one of my favourite tools for playing over a background track: an automatic lowpass ducker, which takes the envelope of the incoming audio signal (guitar) and automatically backs down the highs on the background track. It help with the overall mix and focus on the played parts. The level of ducking and the release time is controlled with the right knob.

A direct result of this project was the Teensy Stereo plate reverb component i posted here:
https://github.com/hexeguitar/t40fx (code)

And finally, i have no idea if the current user discovered this, but since it's been a year...
One special combination of footswitch presses might result in an unexpected behaviour of the pedal: