Sounds like: A long falling sweep that lands on a hard thump at the end.
A falling pitch sweep that lands on a hard, punchy impact hit at the end — used to punctuate a transition or a big structural moment, combining Sub Drop FX's fall with a percussive landing.
Open this patch in the interactive PatchpadCorrected: Track 1's falling sweep no longer uses an LFO on a non-existent 'PIT1' destination. Digitone II's FM DRUM machine has a native pitch sweep — STIM (sweep time) and SDEP (sweep depth) — so Track 1 is a pure Sine FM DRUM voice whose pitch falls by itself over ~1.2 s (STIM 70), with body DEC and the AMP DEC matched (100) so the tone dies as the pitch bottoms out. Track 2 (the impact) stays on the FM TONE machine: ALGO 8 with a very high RATIO A and heavy FDBK — in ALGO 8 the feedback operator is B1, which feeds output Y, so MIX 0 (both outputs) is required for FDBK to be audible — pushes it toward an inharmonic near-noise click; both operators' LEV are set explicitly because B1 reaches Y through an envelope-affected path. Trigger Track 2 exactly on the step where Track 1's fall lands. Parameter values (TUNE/STIM/SDEP scales aren't documented) are starting points to adjust by ear.
Both tracks can use AMP PAGE 2 MODE AHD (SY machines default to ADSR, so set it explicitly), since neither needs to sustain. Both tracks use SY RAW's Digital machine (melodic tracks 1-8 don't have Analog machines available -- those are drum/cymbal-track only), Track 2 leaning on SY RAW's OVER for grit on the click. Corrected: this LFO used to target an invented 'Pitch' destination — Syntakt's LFO destination list (manual Appendix C) has no direct pitch option, so it now targets the machine's own TUNE knob (parameter 1), the real route to pitch modulation. (For hard one-shot pitch falls Syntakt also has native sweeps: BD MODERN's SWEP sets pitch-sweep depth and time.)
LFO 2 is Summit's per-voice LFO hardwired to oscillator pitch via its own section's Depth knob -- setting it to ONE SHOT (menu-only) turns it from a free-running cycle into a single falling ramp per note, the closest real Summit equivalent to a dedicated pitch envelope. Layer A carries the sweep, Layer B the impact hit stacked underneath; Summit has no per-layer delayed-trigger, so to land the impact exactly on the sweep's landing point, play/sequence Layer B's note slightly after Layer A's rather than expecting one keystroke to time both automatically.
Osc 1 is BasicWaves with Morph at 50 (pure sawtooth): the Morph knob runs from a square (0) through a sawtooth (50) to a double sawtooth an octave up (100), Sym only changes the pulse width below 50, and Sub adds a sine an octave down (0 here). Osc 2 is Noise: Wave is the noise Type (particle through white to metallic), Timbre is the Rate and Shape is the Balance with a tonal wave. Mod Matrix: the CycEnv row to the Pitch 1+2 column at -100. The falling pitch comes from the Cycling Envelope (Fall 55, matching the ~1.2s of the main Envelope's Decay) routed through the Modulation Matrix to oscillator pitch at a large negative Amount; the 'impact' character comes from the Envelope's very short Release (5) snapping the sound off right as the fall bottoms out, rather than from a genuinely separate percussive layer. Values are on MiniFreak's native 0-100 scale.
M1 in Envelope mode routed to CV1 gives a real programmed pitch fall -- when DEST is a CV/pitch destination, Typhon's LVL parameter is scaled in semitones rather than the usual 0-100 (confirmed from the manual's CV-scaling explanation), so LVL -24 means a full 2-octave drop, not '-24%'. Typhon is paraphonic with one shared filter/amp per voice, so the impact 'landing' here comes from AMP ADSR's short Decay/Release rather than a second independent percussive layer -- if a harder, more separate-sounding impact is wanted, layer in an external hit rather than trying to build two fully independent envelope stages out of Typhon's single Filter/Amp EG pair.
Hydrasynth triggers every module from one note-on, so sequencing 'sweep, then impact' out of a single voice relies on ENVELOPE 4's own DELAY stage (1150ms) to hold the Noise generator silent until right as ENVELOPE 3's pitch fall (also ~1200ms) bottoms out -- a genuine use of the free-assign envelopes (3-5) beyond the pre-wired ENV1->Filter/ENV2->Amp pair. Mod Matrix depth is -128 to +128 on the hardware; the Osc Pitch destination spans +/-12 semitones, so the -100 fall is a bit under an octave, dial by ear.
This is a two-part FX (sweep + impact) — on synths without independent multitimbral tracks, the impact hit may need to come from a second synth/sample layered in.