Hybrid Synthesis

Take half a sample and half a synth, keeping the realism while gaining the ability to morph.

Related

SynthesizerSamplerThe DX7 and FM synthesisContemporary

The question

A sample is a photograph, realistic but hard to reshape; a synth is a sketch, flexible but short on detail. Hybrid synthesis puts both in one instrument, and the question is the division of work.

How it works

A sample can pass through the synth's filter and envelope for new dynamics. A synth layer can fill missing low or high energy. A sample can trigger a synth, so a real attack leads into a synthetic tail. Samples now share one keyboard and modulation system with FM and wavetables. The division follows frequency and time: the sample owns attack and noise, the synth owns sustain and transformation, or the reverse.

Settings and what you hear

Two layers starting together sound thick, but a small phase or level mismatch muddies them. When the sample supplies the attack and the synth the tail, level must be smooth at the join or it sounds like another note. Filter and envelope on both layers double every adjustment, so tune one at a time. Detuning makes layers beat; a little widens the tone, too much makes pitch unstable.

What to listen for

Hear a piano layered with a pad and listen for the seam between attack and tail. Then hear distorted guitars with a saw lead and decide which layer supplies midrange. Finally hear the bass; whether it is sampled or synthesized usually shows in attack and tail.

Common misconceptions

That hybrid means stacking two layers; that the sampled layer is always more realistic; that phase and level joins need no attention.

Sources

• Curtis Roads, The Computer Music Tutorial — hybrid synthesis checked, not quoted
• Udo Zölzer, DAFX — Digital Audio Effects, hybrid instruments checked, not quoted

Used for fact-checking only; all prose is original.