Recently in Development Category

up goes the posty!

I've decided to revisit my Arduino synth project from last September in hopes of creating a versatile synthesizer shield. I'm rather partial to the digitally-controlled-analog approach. I had an XR2206 function generator IC lying about, so I decided to put it to work as a possible core/VCO of this endeavor. It's quite easy to set up for accurate sine wave generation though driving the frequency with a convenient voltage is still something I'm figuring out.
Datasheets always seem to get a little vague just in the real clutch areas I need to focus on - a circumstance I find myself in often when getting to know a component, I suppose I'm a bit impatient and would rather experiment than attempt to decipher datasheet specs which I'm unfamiliar with. - And of course, why not? - the experimentation is the fun part! As a kid I remember acquiring new transformer figures and excitedly attempting to morph them without consulting the highly visible photo-instructions printed on each package. It's efficient to approach a new situation with proper procedure dictated to you - but that always leave me asking, "Why is that the proper method? and is it really the best way?" more to come . . .

Here's the first working version of the Staccato guitar effect pedal. I ended up choosing the name based purely on sound description. It uses the Ampeg Scrambler distortion circuit and passes the signal through a Vactrol for a softened gating effect. Every time I try to record a sample of it in action, I end up playing around with it much longer than necessary. But this is a good sign.Controls from Left to right:Pots - Texture, Blend, Rate, WidthFootSwitches - Bypass/Power, Staccato-ON/OFFThere's switch built into the texture pot that acts as a big ol' gain boost as well as a DC Jack in the rear with reverse polarity protectionHere's a sample I recorded off of a little practice amp I rescued from the dumpster. It starts off Dry, then uses the straight distortion, and finally, adds the staccato gating/tremolo effect:Staccato Proto sample AAC 1,009KB

I've been working on a guitar effects pedal based around the rare and coveted Ampeg Scrambler. I used almost all the original components specified in the schematic and integrated a simple polarity protection for the DC jack. The biggest enhancement I've added is a sort of vibrato effect as an optional modifier to the texture control. I find the effect quite interesting, but I have a hunch there's a simpler way to achieve it. Currently, I have a timer circuit driving a makeshift vactrol (LED taped to photoresitor). The main circuit's texture control is then fed through the vactrol's variable resistance. I'm concerned that driving the vactrol's LED and 555 timer in addition to the rest of the pedal will create an impractical strain on battery life. Hmm, I should probably measure the circuit's current consumption to learn more. More to come.

Building The OpenEEG

I'm currently working on building my very own EEG via instructions from the OpenEEG project. It's a fascinating project to say the least. Above is a shot of one of the active electrodes I'm using with the project. These electrodes are then encased in silicone and wired to the main enclosure via shielded cable. I'll have some readings/results posted as soon as I get some fine silver fashioned into a comfortable interface.

I ran across this video posted a while back on Hacked Gadgets regarding a research project being conducted at the University of Plymouth.

I am currently conducting research along the same lines but my concept for utilizing the EEG signal differs signifigantly. In this usage the computer is basically "playing along" with a live reading of the subjects mental state. This approach is intruiging (and seems quite enjoyable for the test subject) but I see the interpretation or judgement made by the programming as a major leap in assumption. The researcher seems to acknowledge this. Perhaps it was the only way to make the dynamic legible and fun. Amplifying the EEG readings and retaining a version to-scale of their raw form is what attracts me to the topic. The ability to flatly reference a commonly invisible/inaudible organic characteristic - and apply that characteristic to active expression. That seems useful.

I had a great time at the Create Digital Music / Make / Etsy Handmade Music Night. Many awesome projects were featured, check them out @ CDM and Make (and their respective Flickr pools).
What made this event extra fun for me was the fact that it was the first time I was able to demonstrate some instruments I've been working on to a very supportive and interested community. I have to say, the positive feedback I received (regarding the atari tube in particular) warmed my heart. I have spent so much time learning the language of electronics over the past few months - toiling over wire and solder - that I almost forgot how good it feels to see someone else enjoy something that I've made. What I see as a noisemaker with a couple of knobs on it becomes an instrument once someone else picks it up and begins to play. That is a very good thing.
A big thanks to everyone who came out to the event - Hope to see you again soon.

The ArduinoSynth is my first attempt at microcontroller programming( and pretty much any coding at all beyond a little html). It took me a bit to get started but it's turning out to be a fun way to learn the language.
So far it's a 12-note monophonic synth with transposition selection via one 10K pot. I'm using a gutted toy keyboard for the switches and a simple low pass filter to smooth the output a bit. Here's the schematic:

Features I'd like to add:
- Another octave (maybe add a transpose switch on each of the next octave, then they can share pins with the first)
- Last note hit priority
- Portamento (note-slide)
- Real sine wave out (no external filter, please)
- Polyphony (I had it working badly, need better math)
- any real keyboard feature in existence(or not) attack, decay, waveform, vibrato, etc.

Source can be found here.
Audio sample here
Sample with no LPF here

I recently attended an Arduino class at Lemur here in Brooklyn. It was fun and moved at a brisk pace. The Arduino programming environment is pretty damn friendly and intuitive.
I'm a bit staggered by all the possibilities microcontrollers open up but keep wondering - how do I turn this thing into a synth? Well I seem to be making pretty good headway via hacking bits of others' sketches. Will report back soon.

Here is the "Smooth Cube" - Two squarewave oscillators pass through a timer to gate rhythms, then a low-pass filter takes the edge before greeting your ears. It also has an input jack to utilize the timer/filter chain for other instruments.
Listen:
Smooth Cube v1.0 (dry) - mp3 2mb
guitar through gate/filter mp3 1mb

The heart of the smoothcube is a circuit I found on Worth Ekik's site:
www.geocities.com/worthekik//segen.html

followed by:
www.geocities.com/worthekik//hysteresis.html

and then capped off with an filter from:
www.oldtemecula.com/theremin/sixthvoice/index.htm

My version of Ray Wilson's Weird Sound Generator is complete! This thing was a joy to build and I learned a lot in the process. I debated adding labels to each knob but in the end I decided I'd accentuate the mystery by leaving them blank. Does that make it an MSG instead of a WSG?
Sample to come . . .

UPDATE:
Here be the Samples, no effects, 1-2mb, mp3:
Interdimensional Jalopy
Auditions for the Tardis Alarm
A Home for Lost Drones

Here we see the simple yet powerful Atari Punk Console in convenient tube form. Yes, my friends, designed for convenience and style - the Atari Tube is a welcome addition to any electro-noise performance. It features a borderline blinding white LED at its center and control knobs at each end for enhanced "twiddlability".
(Ear plugs not included . . . but recommended for square-wave haters)

UPDATE:
Listen to a sample - Atari Tube V.0.2 (w/reverb) mp3 2.4mb

It may be full of holes, slightly unreliable, and in need of some touch-ups, but it's mine and I'm proud. I didn't design it, Worth Ekik did. I etched it from a copper clad board with Ferric Chloride. And it was fun.

Aww, take a gander at the "Lil' Captain". Although I was unable to put in most of the finishing touches I intended (check out the hovering gain knob), Dad still loved it. Hey he's the one who taught me how to solder in the first place. He was an electronics engineer in the US Navy. I told him how frustrating I found resistor color codes and he agreed. Due to slight color blindness he almost wasn't admitted into the service. He explained,
"They had to give me a special test to get in. A guy held up a yellow pencil and a blue pencil and asked - 'Which one's yellow?' I pointed to the bright yellow pencil, and he said 'Fine, you're in.' "
Ah the rigorous scrutiny of military enrollment. Happy Father's Day, Captain Mel!

Decided to use a prescription bottle as a case for my VGA coupler. This somehow seems to say "narbotic" to me. Maybe it has some future as a logo/icon for this site.

Did you ever notice when you think of puzzle games you often think of tile-matching games specifically?
Check out A History of Matching Tile Games from jesperjuul.net.