Tag Archives: DIY electonics

sip4: cricket v. space invader

by Larry Dunn, August 6, 2020

In week four of Synth in Place, the online course in DIY synthesizers taught by Kirk Pearson of Dogbotic sound labs, in collaboration with Thingamajigs, we focused on the basic components and technology of commercially produced music synthesizers, and we looked at plans for making two simple synths: one that sound like crickets, and one that can replicate the sounds of 1980s Atari games like Space Invaders.

Our inspiration this week came from Thaddeus Cahill’s prescient 1897 invention, the Telharmonium. This awesome contraption was a synthesizer long before the invention of synthesizers, music amplification before the invention of amplifiers and loudspeakers, a music streaming service long before the internet. Sadly, the Telharmonium was never a commercial success, because it required the nascent telephone network for transmission services. But the demand for telephone service grew so rapidly, that there was no available bandwidth. However, its concepts didn’t disappear completely, as they led directly to development of the Hammond organ. And where would jazz, and rock, and church music be without that?

Breaking down the inner workings of a commercially produced music synthesizer was a revelation for me, as I’d never put much thought to how they work. I’ve just always been content that they make cool sounds. As an introduction, we fist learned that all the commercial synthesizers out there are using the same fundamental technologies and components to synthesize sound, whether those sounds are in the realm most people would call music, i.e., imitating the sounds of acoustical music instruments, or less readily recognizable sounds we’re more likely to hear in the experimental music realm.

We also learned that there is an east-west divide in the synthesizer world, not in underlying technology, but in the nature of the human-to-machine interface, the mechanisms the operator uses to elicit sound from the electronic beast.

Robert Moog at his synthesizer in 1970

East coast synthesizers typically provide a primary interface in the form of a piano- or organ-style keyboard to play the instrument, along with various knobs and switches to customize the nature of the sound. The epitome of this east coast style are the Moog synthesizers, the name that many people think of when the topic of synthesizers comes up in conversation. Robert Moog (1934-2005) was an engineer, not a musician. So he spent a lot time with musicians when he was designing his device. His objective was to make the Moog Synthesizer something musicians would find interesting and easy to play, thus, the keyboard interface so you can play it like a piano or organ.

Moog presented the first public live demonstration of his synthesizer in 1964 at the Audio Engineering Society’s New York convention. A 2014 video made by Moog’s company looks back on that day and the legacy of the founder’s creation.

Soon thereafter, it was clear that the Moog Synthesizer was an instrument musicians could and would actually play, to amazing effects. Composer and performer Wendy Carlos blazed the trail for the possibilities of the Moog in the classical realm with her 1967 release Switched-on Bach. And Keith Emerson, of the power trio Emerson, Lake & Palmer, rocked the pop world with his Moog break in bandmate Greg Lake’s Lucky Man, changing pop music forever.

Stay tuned.

sip2: amazing oscillators

by Larry Dunn, July 21, 2020

Create the Future! Building our own amazing oscillators was the objective for week 2 of Synth in Place, the online course in building DIY electronic music-making machines, taught by Kirk Pearson and presented by Dogbotic sounds labs and Thingamajigs. We took our inspiration for this challenge from a couple of truly awesome, and famous, installations, made by pioneers in the electronic museum field. One of these was composer and sound artist David Tudor‘s Rainforest V (variation 1), at the Museum of Modern Art in NYC, as shown in this 360° video.

Another inspiration came from Daphne Oram of the  BBC Radiophonic Workshop, which she founded in 1958. Her Oramics Machine is a visual synthesizer that uses drawn images to create sounds.

Of course, our first oscillators could not even scratch the surface of the genius of the work of these transformational thinkers and makers of electronic instruments. But we nonetheless are doing our work in homage to their path-setting work.

Oscillators are a foundational building block of electronic music synthesizers. For the uninitiated, an oscillator is an electronic gizmo that makes electrons move back and forth in a normal predicable manner. That predicable pattern can be exploited to activate other electronic components such as led-lights and speakers. With the proper setup of circuits and wiring to control the frequencies in the pattern of electron movement, what comes out of a speaker in such a setup can be pitched sounds in the range we typically call music.

Our first oscillator, a flashing LED (screen shot from Kirk Pearson demo video)

Using a breadboard (a temporary circuit board made for prototyping electronic gadgets); a 555 Timer (a ready-made microchip that can control electron pulses in a variety of ways, depending on how you connect it); a handful of capacitors, resistors, and wires; a bare-wire LED bulb; a potentiometer; a small speaker; and a 9-volt battery, with snap-on connector; we set out to create the future. Our first oscillators evolved through several versions. The first, show above, implements a simple strobe light. The frequency of flashing is controlled by your choice of capacitors. If we add a potentiometer (a sort of switch that can be used to vary the flow of electrons) and a speaker into our design and rewire things a bit, we suddenly have a user-controlled noise-making machine. And if we can get the frequencies in the right range, our noises will be pitched sounds we could call music. Below is a look at that setup.

Prototype sound-producing synthesizer (screen shot from Kirk Pearson demo video)

For the final trick, we ventured into Daphne Oram territory. Remove the potentiometer and do a bit of rewiring to connect a piece of corrugated cardboard filled with a heavy smear of pencil lead (graphite, i.e. carbon, i.e., a conductor of electrons) using an alligator clip in contact with the graphite smear, with a bare wire at the other end suitably connected to the breadboard. Use another wire of the same configuration, similarly connected, and you can “play” the graphite smear using a drawing gesture with the other alligator clip. Here is the way that setup looks.

Crude homage to Daphne Oram (screen shot from Kirk Pearson demo video)

I struggled to get my own version of these oscillator variations working properly. These components, especially breadboards, can be temperamental, to begin with. And whatever manual dexterity I once had (which was not that much) is fading fast with age. As arthritis and other woes take up residence in my hands, you can call me Klutzy McFumblefingers. But, despite the challenges to actually get these things working, learning how they go together to make newly-imagined instruments is a thoroughly engaging experience.

Stay tuned.