Gecho is a polyphonic, pocket synthesizer with interactive controls
How it works: TL; DR
Instead of knobs, it has touch-less sensors that react to your fingers. It also has very sensitive microphones that pick up your singing, whistling or tapping. The collected signal is fed through a group of variable-resonant filters, forming chord-progressions. At the same time, environmental noise peaks disturb the filters settings, creating complexity of sounds.
Intro video + credits
Entire soundtrack in this video has been produced by Gecho and consists of one unedited, uncut performance with no extra added effects (except for fading in waves and wind sound effect at the very beginning and end, as they are separate "channels").
Special thanks to the guys from "The Black Pitts" of Dublin (also for lending the electric guitar seen in other demos). Check out their newly released album.
Some footage and imagery has also been used from the wonderful pixabay.com which you've recently seen here on Kickstarter. Thank you!
I tried to make a music box using the current technology, replacing steel comb, pinned cylinder, cogwheels and springs with crystal oscillators and power cells... but I ended up with something way more complex. It can be a music box - with a click of the button, it starts playing melodies straight away. But it can also be so much more...
Gecho doesn’t try to hide its printed circuit board and some electronic elements. You can touch them – actually, you are encouraged to touch them, nothing will break!
While you can’t see the currents flowing through copper traces, there are twenty-nine colourful lights to show what is going on inside... and because interaction is embedded deeply in the spirit of today’s technology, even our music box must not stay inert. It can hear your voice, pick up frequencies of your musical instruments, remember and play them back to you. It has four sensors to measure distance of your fingers hundred times per second.
It senses magnetic fields and infra-red light, expanding your senses... and it knows how to translate these invisible forces to something you can hear.
But most importantly, even with the very basic program, Gecho creates unique ambience for your ears.
Eager to explore it?
What people said
"I've personally tested an early iteration and it was pretty amazing.
I'm not good with the technical stuff, but in layman terms it is a box that turns any noise into music. So if you bang on the table, whistle, touch a fork on the wall, turn on a forklift, operate a piledriver, it all becomes music together, somehow.
I tried my best at the beginning to make sounds out of tempo and as unharmonic as possible and it all became this sort of strange out-of-this-world melody. The funny thing is that the more I did it, the more I was entangled by it, like an ouroboros of sound, the brain eating itself in its meaning.
I don't know how to explain it better..."
-- Nicholas Amorim, hobbyist composer, singer, drummer & guitars maker apprentice
"When I first saw the Gecho I was intrigued.
When I touched it I was immediately mesmerised. My world just took on another dimension that I was in complete control of - it is amazingly cool."
-- Mike Dee, mobile games designer & enterpreneur
"Gecho is deeply meditative and amusing at the same time. The experience enables you to explore your hidden feelings, which you have never been able to put in words. It's like classical instrumental music with you being in the place of a composer. It is difficult to put your finger on it, but as soon as you put your hands on it you'll realise it's unputdownable. So I guess the best way how to explain what's the thing like is to say - it's addictive. First time I took it to work, it was grabbed from me immediately and only returned towards the end of the day with great reluctance."
-- Pietro, music enthusiast, amateur guitarist and poet, proud owner of Gecho sr.n.0010
How it works
Here are a few videos that explain theory, anatomy and demonstrate Gecho in action:
Programming the music
There are four ways to program your own songs.
• Using buttons
• Using magnetic ring, a quicker method to input notes
• Tone recognition via microphones (singing, whistling, piano app)
• Tone recognition via line-in (electric guitar, classic guitar with pickups)
• And, via USB cable from your PC, running a dedicated application, which is currently in WIP stage
Few things to assure quality of your experience
• Find a quiet place. It is much better for your ears than trying to set volume too high – besides, too much surrounding noise may saturate the microphones.
• Get a good pair of headphones, ideally those which do not artificially boost bass or treble. I haven’t tested many, but Koss PortaPro or Audio-Technica's ATH-M50 sound pretty good.
• If it does not sound good enough, attenuate inherent noise and excessive bass using equalizers (that’s what the four buttons do while playing).
Prototypes depicted in videos and photos, vs. final product
The board (which is a third-generation functional prototype) looks and essentially is the same as what the real product will be – although I assembled these prototypes by hand, machine (which is only feasible at larger volumes) would get similar result and identical functionality.
The box may differ, I haven't settled on final design yet. At the moment I am negotiating with EU manufacturers who can produce volumes of glued box from real wood, and local artist who makes lovely, artistic pieces by hand.
Batteries will be 3x AA, and battery holder will be either soldered to PCB or glued to the box. We'll see (depending on the box).
Board size is 86mm x 53mm (3.386" x 2.087"). Dimensions of final product will be determined by box walls thickness.
But will definitely fit into your pocket!
Taking picture of LED lights is notoriously hard, how they appear in the photos and videos does not represent the vividness and sharp colours of the real thing – they look rather pale with white centres, as the light is too bright and monochromatic. I refrained from retouching the photos, and do not have analogue camera at hand, so just bear that in mind – lights are far more vivid and saturated than seen here.
Also, the outcoming sound has such a dynamic range that it took me good while to figure out how to passably record it. Besides, part of the whole experience is noises from the real world and what happens in listener’s head... hope videos still give you a sufficiently good idea.
For prototypes I ordered cheaper HASL plating, but in next batch the soldering pads will be most likely ENIG (nickel with thin layer of gold, so the pads won’t oxidize until you decide to solder something on them).
What will you get in case you want to progress the software? I am making available a framework that allows you to create your own “channels”, enabling your custom program to talk to board’s hardware and peripherals effectively.
It includes routines/functions for:
• Audio codec handling (inputs and outputs)
• LEDs and buttons, neatly abstracted in few different ways (macros, functions)
• DMA transfer from proximity sensors (so the impact on main program loop is minimal)
• Magnetic sensor and its calibration
• Storing persistent data (e.g. user content and settings) to battery backed-up region of SRAM
• I2C examples to show how to control additional peripherals (if you decide to attach some)
• Sample playback example, thanks to ST’s “ART accelerator” the board is capable to play audio directly from Flash memory (as if it was in SRAM – it is one address space)
I have started writing tutorials to demonstrate basic concepts of working with the board.
Hope it will inspire hobbyists familiar with 8-bit microcontrollers to move on to 32-bit ARMs. There is lot of great boards from manufacturers and other groups, you can buy various shields for them (sensors, displays, audio...) however, my board might be handier specifically for interactive, sound/music making applications. It was custom designed for one such application, and left open to host your own ideas.
Go ahead and add a Bluetooth module, then control this thing with any controller you have at hand (unless you mind the small lag).
Or implement the MIDI input. This would be sidetracking for my project, which wants to stay self-contained and independent on additional gear - your project may differ.
Just keep in mind, the input is a 12-bit ADC so not really hi-fi. This was not critical for my application, which merely needs to record noises, voice or tones from guitar. On the other hand, audio output chip is perfect: CS43L22 - up to 24bit, 96kHz, 98 dB Dynamic Range, 88 dB THD+N, 2 x 44 mW into Stereo 16 Ω @ 2.5V. Contains analogue/digital mixer and lot of interesting stuff. It even has small speakers driver, connect them if you dare.
Few things I will probably add soon:
Serial-to-USB communication at run-time. This is what I haven't implemented yet, but will be very useful (either for MIDI or custom communication drivers).
Because proximity sensors can be used also as IR receivers, I am considering adding support for remote controls – might be handy. So far it reacts to remote, counts & measures edges, however remotes do not just emit plain code of the button, there is a "carrier wave" to be decoded. Normally you use custom peripheral, but perhaps this MCU is fast enough for it...
For sure you will come with many more cool ideas!