joranalogue/collide-4

Collide 4

Joranalogue Audio Design

Fully analogue quadrature spectral computer based on the lock-in amplifier concept. Features a pingable variable-bandwidth bandpass filter with self-oscillation, a through-zero sine/cosine quadrature oscillator, a Hilbert transform network, dual ring modulators with output lowpass filters, and an extensive output section including magnitude and phase analogue computing outputs.649

Capabilities 5

Frequency Shifterfrequency-shifter
Frequency shifting is achieved by enabling the Hilbert transform (Δ90° switch position) and listening to the X'+Y' or X'−Y' sum/difference outputs. The oscillator sets the shift amount; symmetry knob transitions between up and down shifting through zero.649
Lock-In Amplifierlock-in-amplifier
Dual-phase (quadrature) lock-in amplifier with magnitude and phase polar converter outputs. Can perform actual lock-in amplitude and phase measurements of weak signals.649
Ring Modulatorring-modulator
Two precision analogue multipliers (4-quadrant / bipolar VCAs) for synchronous detection. Normalled from input section and oscillator; can be overridden via patch cables. Followed by lowpass filters with selectable time constant.649
Through-Zero Quadrature Oscillatorquadrature-oscillator
Through-zero sine/cosine quadrature oscillator (I and Q outputs). Operates in VCLFO or VCO range. 1 V/octave exponential FM and through-zero linear FM inputs with paired polariser knobs.649
Variable Bandwidth Filtervariable-bandwidth-filter
Temperature-compensated variable bandwidth bandpass filter with self-oscillation capability. Can serve as a sine wave VCO when self-oscillating. Pingable via the Ping Input.649

Jacks 21 — 12 in / 9 out

NameSignalVoltageDescription
Inputs (12)
+ InputaudioPositive differential AC-coupled input to the preamplifier. The preamp input signal is the voltage difference between the positive and negative sockets.649
- InputaudioNegative differential AC-coupled input to the preamplifier. The preamp input signal is the voltage difference between the positive and negative sockets.649
Filter Centre Frequency CVcvModulates the filter centre frequency at 1 V/octave. Temperature compensated for accurate pitch tracking.649
Filter Resonance CVcv≤5VModulates filter resonance; +5 V corresponds to maximum resonance.649
Filter Width CVcvModulates the filter bandwidth at approximately 1 V/octave.649
Gain CVcvModulates the filter output gain at 12 dB/V.649
Oscillator Exponential FM CVcvExponential FM input for the oscillator at 1 V/octave in audio mode; sensitivity is approximately 0.66 V/octave in low frequency mode.649
Oscillator TZFM CVcvThrough-zero linear FM input for the oscillator. The paired knob is a polariser setting modulation depth and direction.649
Ping Inputtrigger≥3VTransient generator trigger input. A rising edge above +3 V strikes the filter to produce a percussive ping sound.649
Time Constant CVcvModulates the detector output lowpass filter cutoff frequency at approximately 1 V/octave.649
X Balanced Modulator InputaudioInput to the X balanced modulator (ring modulator). Normalled from the input section; can be overridden by patching a cable here.649
Y Balanced Modulator InputaudioInput to the Y balanced modulator (ring modulator). Normalled from the input section and oscillator; can be overridden by patching a cable here.649
Outputs (9)
Difference OutputaudioDifference (X'−Y') of the two detector outputs. In frequency shifter mode with Hilbert enabled, provides the opposite direction of frequency shift.649
I OutputaudioIn-phase sine wave output of the quadrature oscillator; low-distortion 10 Vpp sine wave.649
Magnitude OutputcvPythagorean magnitude of the (X', Y') vector. Always positive voltage; computed as sqrt(X'^2 + Y'^2). Represents total detected signal amplitude regardless of phase.649
Monitor OutputaudioOutput of the input section (preamp + filter + gain VCA) before the balanced modulators. Analogous to the monitor output on lab lock-in amplifiers.649
Phase Outputcv-10V to 10VArctangent phase angle of the (X', Y') vector. 18°/V scaling, full 360° coverage, range −10 to +10 V. Note: output may switch rapidly between extremes at 180°.649
Q OutputaudioQuadrature (cosine) sine wave output of the oscillator; 90° phase shifted relative to I, low-distortion 10 Vpp.649
Sum OutputaudioSum (X'+Y') of the two detector outputs. In frequency shifter mode with Hilbert enabled, provides one direction of frequency shift.649
X' OutputmixedDirect output of the X channel detector lowpass filter. In lock-in use, represents the in-phase component of the detected signal.649
Y' OutputmixedDirect output of the Y channel detector lowpass filter. In lock-in use, represents the quadrature component of the detected signal.649

Parameters 16

NameTypeRangeBehavior
Filter Centre Frequency Knobknob22Hz – 22000HzSets the centre frequency of the variable bandwidth bandpass filter in free mode. In track mode, the filter follows the oscillator frequency.649
Filter Gain Knobknob0dB – 60dBPost-filter gain VCA. Primary goal is to provide a strong undistorted signal to the detector; can also be pushed into clipping for post-filter overdrive.649
Filter Resonance KnobknobControls filter resonance via a feedback path. At sufficient width and resonance, self-oscillation is achieved turning the filter into a sine wave VCO.649
Filter Width KnobknobSets the bandwidth of the variable bandwidth filter. At minimum, a narrow 2-pole bandpass; at maximum with centred frequency, spans 22 Hz to 22 kHz.649
Free/Track SwitchswitchIn 'free' mode the filter centre frequency is set independently; in 'track' mode it follows the quadrature oscillator frequency.649
Gain Modulation KnobknobBipolar polariser knob setting the modulation depth and direction of the gain CV input at 12 dB/V.649
Hilbert Transform SwitchswitchX=Y bypasses the Hilbert network (both balanced modulators receive identical signal). Δ90° enables the Hilbert transform, creating 90° phase difference between X and Y signals for frequency shifting.649
Oscillator Coarse Frequency Knobknob22Hz – 22000HzSets the coarse oscillation frequency. Audio mode range: 22 Hz to 22 kHz. Low frequency mode total range: 2.8 mHz to 180 Hz (1 Hz with both knobs centred).649
Oscillator Exponential FM KnobknobPolariser knob for the exponential FM input. Centre is 0 (no modulation); maximum is +1 V/octave and minimum is −1 V/octave in audio mode.649
Oscillator Fine Frequency KnobknobFine frequency adjustment for the oscillator. Range is 5% of the coarse knob setting (6 semitones in audio mode).649
Oscillator Frequency Range SwitchswitchSelects VCLFO (low frequency) or VCO (audio frequency) mode for the oscillator. In audio mode, also AC-couples the TZFM input.649
Oscillator Symmetry KnobknobSets the symmetry/bias of the TZFM. At centre, the oscillator stops; movement in either direction provides asymmetric TZFM. At maximum or minimum, provides linear frequency control. Also useful as a frequency shifter direction control — smoothly transitions through zero.649
Oscillator TZFM KnobknobPolariser knob for the TZFM CV input. Sets modulation depth and direction; inverts the CV signal when set in the left half of its range.649
Preamplifier Range Switchswitch-20dB – 30dBRotary switch adjusting preamplifier gain in coarse steps from −20 dB to +30 dB. Unity gain (0 dB) and 'off' (mute) positions included.649
Time Constant Frequency Range SwitchswitchSelects the frequency range of the detector output lowpass filters. Audio mode: 22 Hz to 22 kHz. Low mode: 150 mHz to 150 Hz.649
Time Constant KnobknobControls the cutoff frequency of both detector output lowpass filters simultaneously. Turning down decreases the filter frequency (reversed from vintage lock-in convention). Range selected by the Time Constant Frequency Range Switch.649

Firmware history 0 versions

No firmware history recorded.

References 2

  1. [649]
    Joranalogue Collide 4 User Manualmanual
    verified 2026-05-21
  2. [650]
    Joranalogue Collide 4 product pageproduct_page
    verified 2026-05-21