Dual Dagger

Shakmat Modular 6HP
VCF FILTER

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Dual stereo filter with independent LPF and HPF cutoff controls. Four analog -24dB/oct filters, assignable resonance, stereo pan CV per filter type, and Link mode for 8th-order stereo bandpass.

Patch Ideas · 6

★ Stereo bandpass sweep
Link ON · LFO sweeps HPF CV (bandpass center) · LPF sets bandwidth · resonance on both edges.
Walkthrough
  1. Flip the Link switch (B, top-left) ON — LPF now follows HPF as bandwidth.
  2. Flip HP Resonance switch (D) ON and LP Resonance switch (E) ON so both edges resonate.
  3. Set Resonance pot (C) to about 2 o'clock; set LPF pot (A) about 9 o'clock (narrow band) and HPF pot (F) at 12 o'clock.
  4. Patch your stereo source: VCO L (Out) → IN1 (jack 5), VCO R (Out) → IN2 (jack 6).
  5. Patch a slow LFO (~0.1 Hz triangle) → HPF CV (jack 3) — sweeps the bandpass center.
  6. Patch OUT1 (jack 6, lower) → Mixer L, OUT2 → Mixer R.
  7. Widen the LPF pot to taste — further open = wider band; almost closed = razor-thin pass.
Signal out OUT1 / OUT2 — stereo audio inside the swept band, ±5V; mostly silent outside the passband.
Listen for A wah-like spectral window that slides up and down the stereo field; both edges ring as the LFO sweeps, like a vocal vowel scanning the spectrum.
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 5 connections. Modules: DUAL DAGGER, VCO L, VCO R, LFO, Mixer. Signals: 4 audio, 1 cv.DUAL DAGGERVCO LVCO RLFOMixerLink: ONHP Resonance: ONLP Resonance: ONIN1audioIN2audioHPF CVcvOUT1audioOUT2audioOUTaudioOUTaudioCVcvLaudioRaudio11. sweeps bandpass centeraudiocv
★ Dual resonant peak
Mono noise → IN1 · sum OUT1+OUT2 · PANLP CV splits the two LP peaks for double-resonant comb.
Walkthrough
  1. Leave Link switch (B) OFF; flip LP Resonance switch (E) ON.
  2. Set Resonance pot (C) to about 3 o'clock (rich peak, no self-osc with Lo jumper).
  3. Set LPF pot (A) at 12 o'clock; HPF pot (F) fully counter-clockwise (out of the way).
  4. Patch Noise (Out) → IN1 (jack 5). Leave IN2 unpatched — IN1 is normalled to IN2.
  5. Patch a slow LFO (bipolar, ±5V) → PANLP CV (jack 4) — pushes LPF1 up while LPF2 goes down.
  6. Patch OUT1 → Mixer CH 1, OUT2 → Mixer CH 2 (or sum to mono).
  7. Adjust LFO depth to control how far apart the two resonant peaks separate.
Signal out OUT1 / OUT2 — two filtered noise streams, each with its own moving resonant peak around the LPF cutoff, ±5V.
Listen for Two whistling formants drifting apart and back together over a noise bed — like two bottles being blown at slowly diverging pitches.
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 4 connections. Modules: DUAL DAGGER, Noise, LFO, Mixer. Signals: 3 audio, 1 cv.DUAL DAGGERNoiseLFOMixerLP Resonance: ONIN1audioPANLP CVcvOUT1audioOUT2audioOUTaudioCVcvCH1audioCH2audio121. IN2 normalled from IN12. splits the two LP peaksaudiocv
★ Sine VCO voice with stereo detune
Hi jumper · resonance max · HPF self-oscillates tracking V/Oct · LPF smooths · PANHP detunes the two channels.
Walkthrough
  1. Power down, set the back-panel jumper to Hi (allows self-oscillation), power up.
  2. Flip HP Resonance switch (D) ON; turn Resonance pot (C) fully clockwise — HPFs sing as sine VCOs.
  3. Set LPF pot (A) about 2 o'clock so the LPF stays well above the sine pitch (clean tone).
  4. Patch Keyboard (Pitch) → HPF CV (jack 3) — V/Oct tracking over several octaves (set HPF pot to mid for a useful range).
  5. Patch a slow LFO (small depth) → PANHP CV (jack 4) — detunes the channel-1 sine vs channel-2 sine.
  6. Patch OUT1 → Output L, OUT2 → Output R.
  7. Tune by ear at one keyboard note: rotate HPF pot until the pitch matches a reference oscillator at the same V/Oct.
Signal out OUT1 / OUT2 — two slightly detuned sine waves tracking V/Oct, ±5V; LPF removes any harmonic crud above the sine.
Listen for A warm stereo sine voice with a slow chorus shimmer from the PANHP detune — Juno-style fattened mono lead spread across the field.
▸ Show diagram
Patch diagramPatch diagram with 4 modules and 4 connections. Modules: DUAL DAGGER, Keyboard, LFO, Output. Signals: 2 audio, 1 cv, 1 pitch.DUAL DAGGERKeyboardLFOOutputHP Resonance: ON · Hi jumper · Res maxHPF CV1v/octPANHP CVcvOUT1audioOUT2audioPitch1v/octCVcvLaudioRaudio121. V/Oct tracking2. detune channel 2audiocvpitch
Resonant kick drum
Hi jumper · self-oscillating HPF pinged by a fast decay envelope on HPF CV — stereo kick with PANHP detune.
Walkthrough
  1. Set the back-panel jumper to Hi; flip HP Resonance switch (D) ON; turn Resonance pot (C) fully clockwise so HPF self-oscillates.
  2. Set HPF pot (F) low (around 9 o'clock, ~60-80 Hz body pitch); set LPF pot (A) about 1 o'clock to tame the click.
  3. Patch a fast AD envelope (5-10 ms attack, 200-400 ms decay, ~5V peak) → HPF CV (jack 3) — each trigger pings the pitch up and back down.
  4. Patch a small fixed offset or slow LFO → PANHP CV (jack 4) for a touch of stereo width.
  5. Trigger the envelope from your clock or sequencer.
  6. Patch OUT1 → Mixer L, OUT2 → Mixer R.
  7. Shorten the decay for a tighter kick; raise HPF pot for tom-style pitches.
Signal out OUT1 / OUT2 — pitched percussive thumps following the envelope, ±5V; silent between hits.
Listen for A bass-drum thump with a pitch sweep down — short attack, body that drops in pitch as the envelope decays, with subtle stereo placement.
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 5 connections. Modules: DUAL DAGGER, Clock, Envelope, LFO, Mixer. Signals: 2 audio, 2 cv, 1 trigger.DUAL DAGGERClockEnvelopeLFOMixerHP Resonance: ON · Hi jumper · Res maxLink: OFFHPF CVcvPANHP CVcvOUT1audioOUT2audioOuttrigTrigtrigOutcvCVcvLaudioRaudio121. pings pitch2. stereo widthaudiocvtrigger
Doubled mono filter (parallel HP+LP peaks)
Mono source → IN1 · both HP and LP resonance ON · sum OUT1+OUT2 for a fat double-peak sound.
Walkthrough
  1. Leave Link switch (B) OFF; flip both HP Resonance (D) and LP Resonance (E) ON.
  2. Set Resonance pot (C) about 2 o'clock (resonant but not screaming).
  3. Set LPF pot (A) about 11 o'clock and HPF pot (F) about 2 o'clock — two peaks in different parts of the spectrum.
  4. Patch a harmonically rich source (sawtooth VCO) → IN1 (jack 5). Leave IN2 unpatched (IN1 normalled).
  5. Patch your envelope or LFO → LPF CV (jack 1) to sweep the LP peak.
  6. Patch a second slow LFO → HPF CV (jack 3) to drift the HP peak independently.
  7. Sum OUT1 + OUT2 to a single mixer channel for a thick mono signal with two independent resonant formants.
Signal out OUT1 + OUT2 summed — one mono signal carrying two resonant peaks (one LP, one HP), ±5V each.
Listen for A double-peaked vocal-formant timbre, like 'oo' and 'ee' vowels stacked, with each peak swept by its own modulator.
▸ Show diagram
Patch diagramPatch diagram with 5 modules and 5 connections. Modules: DUAL DAGGER, Saw VCO, Envelope, LFO, Mixer. Signals: 3 audio, 2 cv.DUAL DAGGERSaw VCOEnvelopeLFOMixerHP Resonance: ON · LP Resonance: ON · Link: OFFIN1audioLPF CVcvHPF CVcvOUT1audioOUT2audioOUTaudioOutcvCVcvCH1audio121. IN2 normalled2. sum monoaudiocv
Mid-Side stereo width filter
Encode L/R to M/S externally (e.g. SumDif) · M → IN1, S → IN2 · PANLP offsets cutoff between mid and side for width control.
Walkthrough
  1. Leave Link switch (B) OFF; both Resonance switches OFF for a clean tone.
  2. Set LPF pot (A) about 2 o'clock; HPF pot (F) fully counter-clockwise (out of the way).
  3. Use an external M/S encoder (Shakmat SumDif or similar): feed your stereo L/R into it; route Mid out → IN1 (jack 5) and Side out → IN2 (jack 6).
  4. Patch a slow LFO → PANLP CV (jack 4) — opens LPF1 (mid) while closing LPF2 (side), and vice versa.
  5. Take OUT1 (filtered Mid) → external decoder Mid in; OUT2 (filtered Side) → decoder Side in.
  6. Decoder L/R → mixer L/R for the final stereo signal.
  7. Adjust LFO depth to control how dramatically the mid vs side spectrum diverges over time.
Signal out OUT1 — filtered Mid signal; OUT2 — filtered Side signal; both ±5V, ready for M/S decoding.
Listen for Stereo width that breathes: when the Side is darker than Mid the image collapses to centre; when Side is brighter than Mid the image flares wide.
▸ Show diagram
Patch diagramPatch diagram with 6 modules and 9 connections. Modules: DUAL DAGGER, Stereo, SumDif Encode, LFO, SumDif Decode, Mixer. Signals: 8 audio, 1 cv.DUAL DAGGERStereoSumDif EncodeLFOSumDif DecodeMixerLink: OFF · Resonance: OFFIN1audioIN2audioPANLP CVcvOUT1audioOUT2audioLaudioRaudioIn LaudioIn RaudioMidaudioSideaudioCVcvMidaudioSideaudioOut LaudioOut RaudioLaudioRaudio11. breathes widthaudiocv

Behaviors

Dual Stereo Filter audio → IN1/IN2

Each audio channel passes through HPF then LPF in series. All four filters are -24dB/oct analog. LPF and HPF frequencies are identical across both channels for precise stereo tracking.

Bandpass via Link Link switch ON

LPF follows HPF. HPF control sets bandpass center frequency, LPF control sets bandwidth. Creates an 8th-order stereo bandpass with resonance assignable to HP and/or LP edges.

Stereo Pan / Detuning PANLP or PANHP CV

Pan CV inputs offset the cutoff frequency of channel 1 vs channel 2 in opposite directions. Positive voltage to PANLP opens LPF1 and closes LPF2, creating stereo filter divergence.

Self-Oscillation VCO Hi jumper + Resonance max + HPF CV

With Hi jumper set and resonance at maximum, the HPF section self-oscillates as a sine-wave VCO tracking V/Oct over several octaves.

Controls

Low-pass LPF Potentiometer Sets cutoff frequency of both low-pass filters (channels 1 and 2).
Controls LPF1 and LPF2 simultaneously · -24dB/oct
Global Link Switch Links LPF to follow HPF, creating an 8th-order stereo bandpass. HPF = bandpass frequency, LPF = bandwidth.
OFF=independent LP+HP · ON=bandpass (HPF=freq, LPF=bandwidth)
Global Resonance Potentiometer Shared resonance control. Applies to HPF, LPF, or both per switch settings. Jumper on back sets Lo (no self-oscillation) or Hi (self-oscillation allowed) range.
Lo jumper=no self-osc · Hi jumper=self-oscillation
High-pass HP Resonance Switch Engages resonance on the high-pass filters.
ON=resonance applied to HPF1 and HPF2
Low-pass LP Resonance Switch Engages resonance on the low-pass filters.
ON=resonance applied to LPF1 and LPF2
High-pass HPF Potentiometer Sets cutoff frequency of both high-pass filters (channels 1 and 2). In Link mode, controls center frequency of bandpass.
Controls HPF1 and HPF2 simultaneously · -24dB/oct

I/O

IN · 7

  • IN1 -5 to +5V AUDIO
    Audio input for channel 1.
  • IN2 -5 to +5V AUDIO
    Audio input for channel 2. IN1 normalled to IN2.
    NORM → IN1
  • LPF CV CV CV
    CV input for LPF cutoff frequency.
  • Resonance CV CV CV
    CV input for Resonance.
  • HPF CV CV CV
    CV input for HPF cutoff frequency.
  • PANLP CV bipolar CV
    Pan CV for LPF: positive voltage opens LPF1 and closes LPF2 (opposite for negative).
  • PANHP CV bipolar CV
    Pan CV for HPF: differentiates HPF cutoff between channels 1 and 2.

OUT · 2

  • OUT1 audio AUDIO
    Filtered audio output for channel 1 (HPF then LPF in series).
  • OUT2 audio AUDIO
    Filtered audio output for channel 2 (HPF then LPF in series).