This is the first of two articles about creating drum sounds with a synthesizer. While many of the popular vintage Roland TR-x0x sounds are generated by analog circuitry, it is possible to achieve a variety of drum sounds using a common monosynth.
My aim is to give you some basic ideas and guidelines of the concept – presented as simple as possible. These are, after all, quick and dirty tips and tricks of a rather complex subject.
First off, you can use an analog or a digital synth, even a softsynth, it really doesn’t matter, although it needs to meet the given specifications, like noise source, voltage-controlled amplifier (VCA), preferably a faster envelope generator (EG) and so on. The output will of course differ from different synths.
Ideally, the synth should have a couple of oscillators (VCO, DCO et cetera) with different waveforms, a ring modulator, a white noise generator, high-pass (HPF) and low-pass filters (LPF) able to self-oscillate, ADSR EGs, separate for filter and amplifier, and in a few cases, e.g. hand claps, a low-frequency oscillator (LFO) with selectable waveforms.
Synthesizing the Kick Drum
Use a LPF that can be sent into self-oscillation. Set cutoff to zero, turn up the resonance almost to max. Use a filter envelope to modulate the cutoff in a quick downward sweep, that is, turn up decay, just a little bit. Also give the sound a little release time. VCF envelope amount should just over half.
Combine this zap or thud sound with a VCO sine wave or a sub oscillator played on a low note. On the amplification envelope, set a short decay and some release. Go ahead and contour these EG parameters; a longer decay and release time can introduce a tonal quality to the sound (but keep attack and sustain at bay). To get it right, you might need to reduce the VCF EG amount and raise the cutoff frequency just to let the lowest harmonics pass.
You could boost a little in the 50-150 Hz range on an EQ to add some bottom depth.
Synthesizing the Snare
Use a white noise source and two oscillators, i.e. triangle wave, at different pitches. Run the noise through an HPF to add more snap.
For a more complex sound, you could use individual VCAs, filters and contour generators for the noise and the oscillators, and then mix the levels of the three sound sources. If you use a separate HPF for the oscillators, try sending it into self-oscillation, to get extra tone and resonance.
Contour the VCA (or multiple VCAs) with a just little decay and release (as always, the attack should be instantaneous and a snare drum shouldn’t sustain).
Use an EQ and cut the low-end. Boost the mids around 500 Hz to add body to the sound, and boost some at 2.5 kHz for extra snap and attack.
That’s it for now. Here’s a sound example of drums made on the microKORG using this concept, https://soundcloud.com/johaneckerstrom/suffix.
The next part will cover synthesized hihats, toms and hand claps, and perhaps even cowbells, claves and metallic percussion. We’ll see.