Defense Mechanism — LSDj Learning Lab shorts: Limit and Vshift, Long Filter Sweeps, Self-Resonating Bass (videos, 2020)

Three short clips from the wave-channel stream series, each carrying one thing the wiki did not have.

Limit and Vshift#

• LIMIT versus VOLUME — the distinction that makes LIMIT worth having. VOLUME scales the signal before everything else, so turning it down destroys the clipping or wrapping you liked: "what if you want to keep the same wave shape … I really like this sound, but it's too loud, and this was the bane of my existence in the early versions of LSDj, because you're just stuck — you can't get it to wrap if the volume isn't high." LIMIT constrains the dynamic range afterwards, keeping the shape. "LIMIT, I think, is almost more useful than anything else on this entire thing."
• Because a synth interpolates across its 16 waves, a LIMIT ramp is "a nice gradual fade without having to use the E commands, which only give you 100, 50, 25 or zero" — the gap between E02 and E03 that several sources complain about (volume-slides, sidechain-pump).
• There is no LIMIT command for the phrase screen; different limit levels mean different synths. A viewer's suggestion that a real-time limit command would be useful is met with "that's a super cool idea, I'm gonna have to bring that up".
• VSHIFT is to DIST what Q is to the filter — "the way that Q is affected by filter and cutoff, VSHIFT is affected by distortion". It shifts the waveform's centre line: 10 lifts it about one step, and at FF everything is silent. In older versions VSHIFT always wrapped regardless of the DIST setting; now it follows it.
• Which is why the parameter has a bad reputation on its own: "somebody told me once, VSHIFT is just a sound-bad button." With CLIP it only squashes the wave against the ceiling — "not the most interesting, just a way to make it quieter, if you need to limit only the top of the wave". With FOLD or WRAP it becomes useful, because the shifted part folds or wraps back in: "that's almost like a pulse-width modulation thing happening" (pulse-width-modulation).

Long Filter Sweeps#

A filter sweep longer than one synth's 16 waves, credited to hypnogram: give synth 1 a lowpass with CUTOFF running 1→2 at a Q around 5–7, then clone it into synth 2 with 20→30, synth 3 with 30→40, and so on up the range. Play the matching instruments in sequence, each PLAY ONCE at SPEED 2 (12 ticks per instrument in his example), and the sweep continues across synth boundaries. "You can tell it uses up a lot of synths to do this, but it is so cool" — and it works best slowly. Diminishing returns at the top: "once you get up to the higher harmonics then, you know, it's like whatever."

Self-Resonating Bass#

Pushing a V (vibrato) command on the wave channel far past ordinary values makes a bass note "kind of like self-resonate with itself" — "it takes the right combination of speed and depth". Two caveats he states while failing to reproduce it live: the sound belongs to one note — "if you want a different note then you really have to go over here and retune this" — and LSDj 7's silky wave may have taken some of it away ("I don't know if this still sounds as good now with the silky wave"). He also concedes he under-uses the technique: "I honestly don't use enough V commands on the wave channel."

Practical takeaways#

• Reach for LIMIT, not VOLUME, when a wave is too loud but sounds right; VOLUME changes the sound, LIMIT changes the level.
• VSHIFT is only interesting with FOLD or WRAP — with CLIP it is a clumsy volume control.
• A sweep that has to last longer than 16 frames is a chain of synths, one CUTOFF slice each.
• Extreme V on a wave bass is a per-note sound: worth tuning for one signature note, not for a part.

Notable quotes#

"You can't get it to wrap if the volume isn't high."

"Somebody told me once, VSHIFT is just a sound-bad button."

Relevance to the wiki#

VSHIFT was the one synth parameter no source in the wiki could use; this gives it a rule (pair it with FOLD or WRAP) and an explanation (it is the DIST-side counterpart of Q). The sweep chain and the resonating bass are two techniques the wiki did not have at all.

To verify#

• The CUTOFF slices (1→2, 20→30, 30→40 …), Q 5–7 and SPEED 2 are spoken while building the patch on stream, from an auto transcript; the shape of the method is clear, the numbers are unverified.
• Whether silky wave really weakened the self-resonating bass is his own uncertainty, not a tested claim (unverified).

Pages touched#

wavetable-programming · filter-programming · pulse-width-modulation · vibrato · volume-slides · lsdj · defense-mechanism · hypnogram · levels-and-headroom