What Is Subtractive Synthesis? – Ableton AnalogNayskii
Subtractive synthesis is sound design that involves removing frequencies from an oscillator. The variation at which frequencies are removed are controlled by factors of decay, filter, envelopes, LFO’s, and amplitude. Filters and the amplitude (volume) are controlled by modulators.
We are Subtractive Synthesizers
Subtractive synthesizers operate in a way that is super similar to the way we speak. Our vocal chords are like an oscillator that produce frequencies. Our mouths are like the filters. The more you open your mouth, the more frequencies that are released from the oscillator. As your mouth and tongue move around, frequencies are subtracted from the oscillator.
Analog is Ableton’s super basic subtractive synthesizer instrument. It’s designed by Applied Acoustics and models classic analog synthesizers. It has a super warm tone to it. Here are basic synthesizer controls to understand:
Oscillators – Ableton Analog has 2 oscillators, the octave and semi. The oscillators produce the sound frequencies. There are 4 sound waves used to produce frequencies – sin wave, saw waves, square waves and noise (sample and hold).
Synth architecture – Click in the global tab near the volume to open the synth architecture. The synth architecture is the signal flow diagram for the synthesizer. A lot of synthesizers, digital and analog, have a signal flow diagram. Massive has a really nice digital signal flow diagram.
Here the signal flow of the oscillators can be adjusted to pass through the filters and amplitude. If the receiving filter is set to low pass mode then the top end gets removed from the signal. The opening and closing of a low pass filter gives the frequency character.
Envelopes – Envelopes shape the sound. There are 2 basic envelops in synthesizers, the filter envelope and the amplitude envelope. The shapes of the envelopes are controlled by the attack, decay, velocity, sustain, time and release parameters.
Attack – How long it takes for a sound to go from its initial value to the maximum value. This is an amount of time.
Decay – How long it takes for a sound to go from the maximum value to the sustain value. This is an amount of time.
Sustain – Is a level between the decay and release.
Velocity – Controls the envelops depth. In Ableton Analog, the Ableton Simpler and other digital instruments the velocity is set on by default. So just keep an eye out for that default setting
Release – How long it takes to go from the sustain level back to nothing. This is an amount of time.
Linear vs Exponential Envelopes – Linear envelopes are super straight sound waves and unique to digitally produced sounds. Exponential envelopes have a natural curve that resembles sounds waves produced in the natural world. Sounds in the natural world are subjects to physical laws like inertia which creates a natural exponential fade and curved sound wave. Quick tip, using linear waves on the amplitude (volume) sounds super artificial, don’t do it.
Basic synths sounds are nothing without channel strips. Channel strips are used to add effects, processing and movement to the synth sounds. Limiters are great for controlling the loudness. The OTT compressor helps add presences to the sound. A saturator will pull the base tones to the front of the sound. Then take a scoop out of the low mids using the EQ Eight for a perfectly warm bass tone.
Additive Synthesis is also a super popular type of synthesis. Additive synthesis is used to call the attention of the music to the fore ground and make bass music sound 3D. Learn about additive synthesis here.