How to Synthesize a Drum Kit
Overview
You can synthesize a full drum kits using a basic subtractive synthesizer. Here are basic recipes to get started. Not only will this allow you to perfectly tune your kick to your song, but also gives you complete control over the texture. I’ll cover the following recipes, demonstrated with screenshots in Vital.
Kick drum
A basic kick consists mainly of a low sine wave with a fast decay envelope on the amplitude and pitch.
Start with a sine wave, and tune it down 2 octaves.
Set the ADSR envelope to have 0 attack and sustain along with about 100ms of hold, decay, and release. Setting attack to 0 will create a nice click at the beginning. To avoid the click, add 0.001s attack.
Next, the pitch of the sine wave should sweep downward towards the root note very quickly. Modulate the pitch of the sine wave using another envelope. Use a similar envelope with decay and release of 100ms and all other parameters turned down. Put some tension in the decay curve so it is not linear.
That is the most basic recipe for a kick. At this point, you should have a deep sub kick that can be used for electronic music. This is just a starting place though. Now you can get creative and push it further.
Take it further by experimenting with:
- Different envelope curves to give more body
- Using different waveforms. Serum has a bass drum wavetable called Analog_BD_Sin which has some slight variation to the regular sine wave.
- Changing the start point/phase offset of the wave
- Adding a noise layer. Serum has noise waveforms for kick attacks to provide that initial click.
- Effects like saturation, distortion, overdrive, compression
- LP filter or EQ with a resonant peak that slides down
- Transient shaper plugins
Hi-hat
There are two types of hat sounds, open and closed. Let’s look at both. For another method of making cymbals using FM, check out Au5: Synthesizing Cymbals With Serum and Create Metallic HiHats with FM Synthesis in Ableton.
Closed hi-hat
The simplest way to make a closed high hat is to use white noise with a quick decaying envelope.
You can also send the noise through a LP filter (little or no resonance), with the same envelope tied to the cutoff.
Open hi-hat
To change a closed hat into an open hat, raise the decay and release to about 0.5s.
If you want to get fancy, modulate the release time with Lift. The quicker the Lift, the lower the Release. This way, quick taps with a fast Lift will have shorter release to act like a closed hat, while a long note press will behave like an open hat.
Crash cymbal
Making a crash cymbal is similar to the hi-hats, except with a longer tail.
Start with white noise and put it through a high pass filter.
Set the ADSR envelope to have a decay and release around 1.5 seconds. Apply the same envelope to the volume and the high pass filter.
The envelope should increase the cutoff frequency of the high pass filter and look something like this:
Claps
Claps can also be made from noise and shaped with the envelope and filter.
A multi-segment envelope is needed, so in Vital, the LFO is used in envelope mode. Draw in 3 or 4 steep peaks of varying tensions like this. Tiny tweaks here can make a huge difference. Play around until it sounds like a clap.
To take the clap sound further, try experimenting with:
- Adding band pass filter with resonance in the mids
- Adding distortion
- Adding EQ to boost highs and lower sub
Snare drum
Making a snare is similar to combining a kick drum and a closed hi-hat. There is a noise layer with a sine wave that has a quick pitch drop, just like the kick, only higher.
Start with the sine wave:
Then set the ADSR envelope to have a fast decay around 100ms and no sustain.
Apply the same ADSR envelope to the pitch of the sine wave, quickly dropping it from an octave higher down to the root.
Then layer in white noise, with the same ADSR envelope controlling level.
This gives you a very primitive snare drum. To take it further, try experimenting with:
- Adding a high pass filter to remove too much low end
- Distortion
- Compression
- EQ
- Gated reverb to make an 80s style snare
Conclusion
These are some very basic recipes to get a drum kit going with a subtractive synthesizer. Get creative and take it further.