About Channels

About Channels, or how Math is not really that hard

What are those "channels" anyway?

It's just a fancy name for program - kind of like washing machine has a program. Gecho has relatively large memory for code - 1MB, of which currrent firmware occupies

Some channels are passive, have no interaction - you can just listen to them. Other react to your input in various forms. Some are for testing and some for settings or programming your own content. The list is long and expanding.

From Random Signal to Arrangemements

Generating Chord Progressions from Random Signal

Few articles with original writing appeared recently with their own interpretation of Gecho, not always entirely consistent with the truth.

In a fraction of them I noticed one misconception being perpetuated: reportedly, Gecho can "compose music out of chaos", i.e., invent melodies and chord progressions that sound nice. But wait, this sounds like a problem for A.I.! It can't really fit into a single-chip synthesizer. Or can it?

Tutorial - Changing sample pitch in real time

Implementing New Voice Type for Melody - Sampled Instrument

Objective: Demonstrate how to expand the functionality using the framework, showing examples of how to:

  • add a new type of voice, played by a real instrument
  • use this voice for melody, by changing pitch in real time


If you haven't done so, please start with the first tutorial in the series to make sure you have all equipment and software ready.

Extras and WIP

Schematics, Diagrams & Work in progress

A peek into inner workings of Subtractive Synthesis block

This is a functional block used by most basic channels - those which play background chord progression with melody or arpeggiator. There is 8 Resonant Low-pass Filters per channel and control logic. Just a sketch - work in progress, will need to redraw it again and add detailed explanation.

Tutorial - How to implement new channel

Implementing New Channel - A Rudimentary Drum Machine

Objective: Demonstrate how easy is it to expand the functionality using the framework, showing examples of how to:

  • add a new channel with any numeric code we want
  • enable or disable standard features that are available, to borrow some functionality from other channels
  • upload arbitrary data into FLASH memory and access it, this is handy for lot of other things too
  • decode binary 16-bit PCM sample data from a standard WAV format

Gecho The Awesome Loopsynth


Successfully funded on Kickstarter!

Gecho has acquired funding for the initial production batch:

Missed the campaign?

Don't worry, we may have few extra units left. To get notified when they become available, please subscribe for the newsletter at this website, or you can "like" or "follow" our FB page. There will be the same spectrum of DIY options as was displayed in the campaign, with more, less or no assembly & soldering required.