4ms Projects

Church of the Friendly Ghost presents

Handmade Music Austin

A series of DIY electronic music workshops, with expert instructors from Bleep Labs, 4ms Pedals, and Eric Archer.

SYNTHS AND DRUM MACHINES?

In a friendly workshop setting, we’ll present a newly-designed series of miniature electronic instruments, called Andromeda Space Rockers. No bigger than a credit card, these projects are designed for DIY’ers like you. They can be built in a couple of hours to make a working drum machine, bass generator, or micro-synthesizer. These fun little instruments love to jam together, and they do it by forming a wireless network to keep the rhythm! They react to the environment as well… for example, the drum machines‘ filter, pitch, and envelope are controlled with light-reactive photocells.

Each workshop will feature a different instrument.
The full series of kits will be available online as well (to be announced soon).

BEGINNERS ARE WELCOME TOO

Basic classes are offered for beginners free of charge, where you can learn to solder and build an easy music project that will prepare you for Andromeda Space Rock.

Or you can skip straight to the ‘Upper Division’ and build one of the Andromeda Space Rockers instruments. Soldering equipment will be provided. To participate in the Upper Division classes you should be familiar with assembling printed circuit boards. An understanding of electronics theory is not required; just patience, hand-eye coordination, and enthusiasm for DIY music.

OPEN JAM AT EVERY WORKSHOP

Of course, there will be an open jam / performance once the instruments are built. We encourage you to bring some pedals and a small amp to plug in your new synth or drum machine and participate in an exciting musical experiment. Huh? Since the Andromeda Space Rockers communicate with each other using infrared wireless, they keep the rhythm automatically – the space will be filled with synchronized sound as you tweak the tones and control the arrangement. The network supports an unlimited number of instruments; we are building a musical organism that reacts to its environment, part human and part machine, and containing the love built into it by your own hands.

Performances are FREE to attend.

CLASS SCHEDULE

All workshops are on Sundays.

4PM – 5:30 Beginner’s Workshop
6PM – 8 Upper Division instrument building class
8:30 – ? Open Jam and featured performance

CLASS DATES

2009

October 18
November 15 (coincides with East Austin Studio Tour)
December 20

2010

January 17
February 28
March 14
April 18

LOCATION

Salvage Vanguard Theatre
2803 Manor Rd
Austin, TX

HOW TO REGISTER

Beginner’s Workshop is free. Upper Division registration is $45 and includes materials. We’re accepting workshop preregistration for Oct 18th and Nov 15th. The first 2 workshops are filling up quickly!

REGISTER VIA EMAIL AT: churchofthefriendlyghost@gmail.com

I finally got around to assembling one of the pcb’s I had printed up for this project, and it works!

The circuit is just an STP16 chip sinking current on 16 common cathode RBG LEDs, and three transistors selecting whether red, green, or blue is active. The 16 buttons are tied to the STP16 pins as well, and all the other sides of the buttons are tied together and run out to the header. An AVR ATtiny84 connects over the header. The AVR “brain-board” is nothing more than the AVR chip itself, plus a button I use to change modes, and an 6-pin ISP header and resistor used for re-programming the chip. Seeing as the parts count could be exactly one 14-pin chip, future version of the board should probably have the option of putting that chip on the board directly.

This approach is unique because it uses one STP16 chip to sink the LED current (like the Peggy 2) and also uses that same chip to produce the scanning that reads the buttons. Thus only 7 pins are needed on a single microcontroller to control a very long string of boards: 3 pins for the three colors, 1 pin for reading the buttons, and 3 pins for shifting bits into the STP16. This is much simpler and equally powerful approach as Sparkfun’s SPI boards, which uses an 18-pin current sink chip, and two 16-pin shift register chips, as well as 13 pins on the IC. I have yet to test how many boards can be controlled by a single microcontroller, so we’ve yet to see how my approach really measures up…

Full color (24-bit, which is 8-bit per “channel”) is possible, as seen in the video. However it’s fairly processor intensive and there’s not many free clock cycles. I’m using a software PWM, so using hardware PWM would speed things up of course.

• Schematic (jpg)
• Schematic (gEDA gschem file)
• PCB image (jpg)
• Totally un-optimized, randomly commented, proof-of-concept source code (avrstudio4 project in avr-gcc): bx3d_tiny84.zip

This is the first draft of an Autonomous Bassline Generator. The melodies are generated by a mathematical algorithm using the value of the Melody control as a seed. So it’s deterministic, not random.

An ATtiny44/84 chip generates Pulse-Width Modulated waves, into an analog resonant band-pass filter, whose frequency is modulated by a photocell. The ATtiny also is flashing an LED to the envelope of the notes, so you can either point the photocell at this LED to get cool old-skool analogue filter sounds, or point it at light/darkness in the room to control it manually. There’s Tap Tempo, as well as IR send/receive for syncing up to other devices!

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A brief demo of an RGB LED button pad I made. This is an older video using a hacked-up PCB from Sparkfun, I’ve since changed my approach to use fewer transistors and drew up some custom PCBs. I’m just waiting for my RGB LEDs from China! The rubber pads are from Sparkfun.

NEW STUFF: See version 1 here

This blog will be a peeking-grounds for oddities that may emerge from 4ms Pedals studio in Austin, TX. If works-in-progress, DIY projects, heat-shrink tubing and flying wires offend you, run while you can

Stay tuned!