Here’s a demonstration, via ToyKeeper, of a Karplus-Strong synthesis patch on the Sequential Pro 3.
Karplus–Strong string synthesis is based on using very short filtered delays to create sounds similar to plucked strings or hammered percussion.
The video is not intended to be a performance or a tutorial, but simply to demonstrate the variety of sounds that are possible with this type of patch.
Here’s an example of using the patch to create legato sounds, closer to a synth lead or an electric violin:
Here’s the details of the patch:
To make a patch like this, basically just start with an init patch, turn off the oscillators, route a plucky aux envelope to the noise level, and turn on tuned feedback (amount = ~62 to ~64, tuning = 24). The rest is just performance conveniences, like the mod wheel, aftertouch, pitch wheel… and some delay.
Create an “exciter”:
– Create an init patch (OctDown + Latch).
– Turn off all the oscillators in the mixer.
– Map aux 1 env to noise level.
– A:0, D:3, S:0, Amt: 127
– Set the filter to state-variable lowpass, cutoff ~874, no resonance
– Enable Tuned Feedback: Amt +61, Tune 24 (Amt varies with temperature)
– Map Slider to Feedback Amt, +4
– Enable Slider latch, and slide it to control whether note grows or fades over time.
– Increase the range which is in tune: Map Note Num to Feedback Tune, +2 (may require adjustment on each Pro 3)
– Map LFO1 to Feedback Tuning
– Map Pressure to LFO1 Amt, +1
– LFO1 Freq 110, Amt 0, Shape triangle
– Map Note Num to LFO1 Freq, +57
– Map ModWheel to Distortion, Amt +127
– Map PitchBnd to Cutoff, +58
– Map PitchBnd to Feedback Tune, -2
– Enable effect 1: DelayStereo, FX Mix 40
– Sync On, Sync Freq 8, Feedback 110, LPF 140
Check out the video and share your thoughts on Karplus-Strong synthesis in the comments!