Roland 303

The Roland TB-303 is a dedicated sequencer/bass analog machine dating back to 1982. The machine was originally released to the market by Roland Corporation to be paired with the then TR-606. The main idea was to provide to instrument lovers an affordable substitute for live bass player and drummer. At the time, the TR-606 got a more solid ground on the market and outsold the TB-303. Basically, it is a drum-machine-sized that poorly imitates a bass guitar with buttons arranged in a keyboard configuration for keying in pitches among other buttons used for editing different sequences.

The TB-303 features a single audio controlled oscillator, which has the capability to be configured to produce a square wave or sawtooth wave. With the use of a single simple-transistor waveshapping circuit, you can create the square wave from the sawtooth waveform. The sound created subtly differs from the square waveform produced by the dedicated hardware commonly found in most analog synthesizers.

There are knobs to control the frequency cutoff, tuning, resonance, decay, tempo, plus volume, and a single envelope generator. It further features a DIN sync jack on its rear for synchronization with other instruments such as the 808, 606, and 202, among others. There is a lowpass filter with-24dB per octave attenuation. There is a very widespread misconception that the filter of the Roland TB-303 is a 3-pole 18dB per octave design but in actual sense it is a 4-pole 24dB per octave.

When programming the sequence, you can determine whether you should accent a note or employ portamento, a very fine and smooth transition to the following note. If you decide to employ the portamento circuitry, you will use a fixed slide time which means that regardless of the interval between the different notes you are working with, it will take the same duration of time to reach the correct pitch. The accent circuitry on the other hand not only increases the note amplitude but also emphasizes on the resonance and filter cutoff. This is what leads to the characteristic hollow ‘wow’ sound when working at higher resonance settings.

The Roland TB-303 further features a ‘user-friendly’ step-time method that allows you to enter note data in the 16-step programmable sequencer. However, the feature, ever since the release of the machine, was famously hard to use, and would mostly result in entering a different sequence than the one the user intended. It has also been reported that users would take advantage of low voltage failure mode where pre-programmed patterns get completely twisted whenever the batteries are removed for a time.

In a nutshell, the main things that make the TB-303 produce that inimitable mystical sound includes:-

A 3-poler filter that gives unique sound
There is always something screwy behind the scenes with the resonance
The accent not only alters the volume but also the envelope and resonance amount too
The screwy interface of the sequencer makes the user enter bizarre lines accidentally
The slide feature is unique and unlike a regular portamento and cannot be copied.