Box of Maps: Looping back to TB-303 inspired music. Part 1

The machine that makes "beeps and swooshes" in dance music

Longterm obsession with an influential device

As someone with a more than passing interest in electronic dance music, I have been obsessed with the Roland TB-303 synthesizer multiple times in my life. In case you aren’t familiar with this device, it was a failed product designed to replicate bass sounds produced in the early 80s. Despite its commercial failure, it was adopted by electronic musicians and became a fundamental tools of dance music. Some fabulous examples include Daft Punk’s song Da Funk or Fatboy Slim’s Praise You (jump in at 3:17 example), and there are countless lists of top songs featuring it if you search around. Beyond these stand-out examples, warble-y synth lines of accented 16th notes gliding between pitches are strewn across all modern dance records, and it is the main instrument of acid house music.

The influence of the TB-303 plays a role in why I’ve returned to it multiple times. Once you recognize its impact, you start to hear it everywhere. I came to know the 303 by way of acid house music: a genre of music that, in the most general sense, uses TB-303 bass lines combined with a drum machine to make repetitive abstract music. As a young person in the 90s, acid house struck the sweet spot on the 3-part Venn diagram between rave music, avant-garde, and ambient music that is best listened to on headphones. I dig the 303, have some favorites in the genre, and revisit my love for the cool things people have done with this device; however, I’m not a purist and have never owned one. My love has been fueled by various emulators and many artists who used repetitive 4-bar synth loops in beautiful ways. It is with this non-authoritative enthusiasm for the synth that I invite you to join me in exploring some of the sonic characteristics and how I try to weave them into the music I work on.

The signal flow

Musically, I often find myself inspired by the 303 workflow, which to me means a mono synth played with a step sequencer for repeated melodic, evolving lines that glide. Let’s consider the components that comprise these musical passages starting with signal generation. The TB-303 has a square wave and sawtooth oscillator (VCO) modulated by a voltage controlled filter (VCF) that is applied with an envelope (ENV. GEN) that is also sent to the voltage-controlled amplifier (VCA). The relevant section is broken out in Fig. 1. There is an accent feature that appears to modulate the amplitude and specific filter effects. The TB-303 also has a glide so that note pitch drifts from one to the next.

Fig. 1. Signal flow diagram of the TB-303

If you’ve never seen these components before, the above diagram may look overwhelming, and that’s okay. The box on the top left generates the main waveform, and the VCF processes the signal that is output (like a guitar pedal would), and there are some knobs that can be tweaked. It’s not super complicated at the signal chain level. The main unique component compared to a typical modular setup is the accent feature, which modulates the filter, amplitude, and envelope (discussed in depth here). Aside from this truly unique signal flow, the single oscillator, envelope, and filter features the nature of the signal generators and processors (ie. how they are constructed, unique features of output, etc.). This “simple” setup presents a limitation and guidepost in electronic music that I sometimes forget: let the electronics speak. The TB-303 sounds like it does because of decisions engineers made when designing the oscillators and filters. This might include considerations like intended use balanced with price points and technology trends of the time. All synthesizers have a unique voice, and the characteristics of its oscillator run through the signal chain is what creates a diverse musical palette.

The waveforms

I was surprised when I first learned that the TB-303 ostensibly outputs either a square or a sawtooth wave, because it sounds more like a mixture between the two. I always attributed this to the filter, but a bit of internet searching revealed an absolutely fantastic 303 page where they show the waveforms with minimal filtering, and sure enough, neither waveform looks like what you’d expect (Fig. 2). So this is cool to know if you’re trying to achieve this sound.

Fig. 2. Apparently what the waveforms on the 303 look like.

The sequences

The signal chain described above is triggered with a 16-step sequencer. Programming these sequences on an original module sounds very tedious, and I am thankful to our forefathers for their hard work :-) Although not technically accurate, I consider the following characteristics to be “303-style”:

1. Repetitive melodic patterns that are catchy and emphasize rhythmic or melodic components

2. Glide/portamento so that notes often transition between one another rather than hearing the attack of all individual notes

3. Rhythmic syncopation where a line is overlaid to help make a steady drum beat more dynamic

4. Evolving filters are applied. In most of the music I listen to, they evolve over the course of many measures, but I don’t think there are any major rules

When these elements are incorporated, my mind usually thinks the music gives dance or house vibes. You would want a few more things to unambiguously be in the acid house realm: squelchy resonance, subtle pitch variations (often due to slowly evolving filters), and accents with glide control.

Learning from the TB-303

Working within limits

The specific 303-style process presents limits by using a mono synth with glide versus a poly synth, resulting in different decisions than one might make if you just approach a keyboard directly. I came at synthesizers from a piano perspective so mono seemed like a major limitation but it’s fun to work out single note lines. Tweaking synths gives me a feeling somewhere between playing an instrument, playing a video game, and programming a computer: a nice place to be.

Use what you learn

The 303 was a ubiquitous tool for an entire genre of music—maybe the guitar of dance music. It is designed to make 16-note loops with gliding lines. I find it fun to lean into the mindset the device gives me. Find a a 16-note gliding loop, throw some effects on and see where it takes you is fun. Although describing styles can feel a little bland, it’s not the worst thing to ask: could this line be syncopated in some way? are these filters evolving?

Thanks

Thank you for hanging with me through this descriptive monologue about the TB-303. I have a few studies planned for coming weeks where I will explore some methods that I find helpful in making musical lines in this style. Would love to have you along for the ride if you’re also an enthusiast.