# listings[].model
Quad analog VCA with dual Ring Modulator and voltage controlled crossfaders

# listings[].title
Compact Eurorack Quad analog VCA with dual Ring Modulator and voltage controlled crossfaders

# listings[].shop_name
LFusion Electronics Eurorack Synth Modules and Parts

# listings[].description
Advanced quad analog VCA module carefully designed by L-Fusion Modular. Offers 4 quality VCAs with linear/exponential control and over 90dB of dynamic range based on new SSI2164 VCA ICs with ultra-low noise and virtually no crosstalk. Module provides inputs to control the VCAs from 0 to 5 Volt CV or bipolar -5V to 5V CV or audio signal. Can be used to attenuate both audio signal and DC coupled CV.

Apart of basic VCA functions module provides very accurate dual ring modulator (four quadrant multiplier) and dual voltage controlled crossfader functions.

In case of ring modulator one signal is patched to ring modulator input and another one in bipolar control voltage designed for modulating with audio signal. Function provides accurate multiplication of both signals which can be used to obtain a large variety of interesting tones. Different wave forms from the same oscillator can be patched to these inputs as well to obtain more exotic wave shapes.

Power saw wave shape: When ring modulator module is paired with our Dual Triangle VCO module and patched saw and pulse waves from the same oscillator it can generate a very interesting wave shape that consists of ramp wave inside of saw wave resembling Mazatec ornaments. Pulse wave can then be modulated with CV which affects the proportion of saw and ramp inside the pattern.

Crossfader function allows connecting input 1 and input 2 and crossfade between them using 0 to 5 Volt CV or bipolar -5V to 5V CV. If more crossfaders are needed module provides jumper to convert second ring modulator to crossfader.

L-Fusion VCA module can also be paired with our (or third party) envelope follower to be used as a compressor. Compressor function attenuates high gain signal more compared to lower gain evening out overall signal strength. When nothing is patched to positive voltage control VCAs are designed to stay open so their voltage could be attenuated via envelope follower patched to subtractive/negative socket. Envelope follower should have to be fed through an attenuator which sets compression ratio. VCA output potentiometers provide high gain of +12Db to compensate for gain loss without the need of external amplifiers.

All potentiometers are precision closed shaft Alpha variety, module is made with high quality electronic components, features rubber knobs with soft touch for easy grip and tactile feedback.

Geeky stuff: Module consists of 8 analog SSI2164 VCA blocks + 38 OpAmps – 317 components in total. Al OpAmps are audio grade from Texas Instruments, with very low drift and offset rated at 0.5milivolt. All OpAmps in audio path are ultra-high dynamic range Soundplus/Burr-Brown type making sure of excellent audio quality and supply voltage noise rejection. Analog calculations are performed with 0.1% precision sourced from high end voltage reference from Analog Devices. Module is carefully designed using 4 layer PCBs to filter out noise and minimize crosstalk between different VCA channels, it provides plenty of decoupling for all ICs based on high end US Kemet and Japanese Nichicon capacitors.

Power consumption: +12V – 125mA, -12V – 110mA

Module width: 9HP

Module depth: 3.8 cm

Input impedance: 100kΩ

Expected source impedance: 0kΩ or 1kΩ

Output impedance: 1kΩ 0.1%

Noise level: -90dB

Testing: Fully tested before dispatch

# listings[].model
4HP Quad Active Mult with two Gate to Trigger converters

# listings[].title
Eurorack 4HP Quad Active Mult with two Gate to Pulse converters

# listings[].shop_name
LFusion Electronics Eurorack Synth Modules and Parts

# listings[].description
Precision 4HP analog quad buffered signal mult module with Gate to Pulse converters on two of its outputs, designed for 3U Eurorack systems. Offers 4x 1 to 3 exact buffered signal copies with 0.1% precision. Very low noise and distortion, top two channels are optimized to handle analog pitch preventing detuning when same pitch CV signal is sent to Oscillator(s) and Filter. Third and 4th buffers are optimized for gates outputting two gate copies as well as 2ms pulse outputs triggered on rising gate edge. Due to diode physics pulse output has a voltage drop of around 0.9V.

These gate to pulse converters are designed to be paired with our 4HP Dual Analog AR Envelope Follower module generating both Attack/Release envelope for VCA and percussive Decay slope suitable for filter FM, oscillator pitch and other funky parameters.

Compact single PCB design. Upgraded version is designed to pass CV voltage to the next buffer if its input is not connected, allows daisy chaining 2x to 6 or 1x to 12 copies. New version also features elongated screw holes and better Burr-Brown audio OpAmps rated with max 0.5mV offset as well as extra parts to allow true 0-ohm impedance on its pitch buffers.

2.0 Update: Temperature stable high end C0G pulse converter capacitors for perfectly even pulse under all conditions.

Power consumption: +12V – 20mA, -12V – 20mA

Module width: 4HP

Module depth: 2.5 cm

Input impedance: 100kΩ

Expected source impedance: 0kΩ or 1kΩ (one of two options upon request)

Output impedance: 0Ω or 1kΩ 0.1% (one of two options upon request)

Noise level: -90dB

Testing: Fully tested before dispatch

# listings[].model
Precision 4HP Eurorack dual analog envelope follower

# listings[].title
Precision 4HP Dual Analog Envelope Follower module, AR envelope generator

# listings[].shop_name
LFusion Electronics Eurorack Synth Modules and Parts

# listings[].description
Compact 4HP dual analog precision envelope follower module with voltage-controlled threshold designed to be used to convert audio signal strength to CV voltage, this signal can then be attenuated and fed to VCA to create analog compressor or expander as well as for sidechaining – lowering the gain of other signals for a cleaner mix.

Module can also be used as Attack-Release envelope generator by sending gate signal to it, it outputs beautiful precision envelopes with logarithmic attack and exponential decay. When paired with our Gate to Trigger converter it can also generate analog exponential decay slopes that sound very good when sent to voltage-controlled filter, these slopes are also useful to modulate different VCO and VCA parameters to create kicks and other rhythmic sounds.

Threshold inputs allow subtracting the envelope with another positive CV output, designed for selecting minimum gain to start the compression. It can be also used to achieve ducking effect for example when kick or other sound is passed to one envelope follower then its output to attenuator and from there to threshold input of to the next follower handling synth voice envelope. However for real sidechain compression synth voice or its envelope would have to be fed to dedicated VCA and its gain controlled with the sidechaining envelope.

Each envelope follower in the module has a discrete core of 9 carefully selected OpAmps, signal rectification, attack, release and threshold stages are based on innovative ideal diode OpAmp topologies with very low offset and high precision even when processing low voltage signals.

• Power consumption: +12V – 80mA, -12V – 55mA
• Module width: 4HP
• Module depth: 3.8 cm
• Attack: 1.5ms - 12sec (exp)
• Release: 5ms - 30sec (exp)
• Input impedance: 100kΩ
• Output impedance: 1kΩ 0.1%
• Noise level: -100dB
• Testing: Fully tested before dispatch

# listings[].title
Eurorack dual analog VCO 16HP module with through zero FM - Precision tracking triangle core

# listings[].shop_name
LFusion Electronics Eurorack Synth Modules and Parts

# listings[].description
Dual analog triangle core voltage controlled oscillator (VCO) 16HP Eurorack module with through zero FM modulation based on SSI2130 ICs; features precision analog exponential converters, triangle oscillator cores, waveshapers as well as high quality voltage controlled amplifiers for wave mixing.

Each VCO in the module outputs sine, triangle, saw and square/pulse waves,also voltage controlled mix of them with sub oscillator an octave below controlled with integrated crossfader mixer.

Both oscillators can be modulated with exponential and linear FM, as well as through zero FM/PM, wave shape and pulse width CV. To ease modulation for each oscillator we have added separate sine outputs with variable gain controlled with modulation knob.

Module also offers master crossfader to mix the outputs of the two oscillators, octave selector switch for each oscillator, as well as knobs for shape, pulse width, pitch and fine tuning. Module is designed using precision voltage reference and other high quality components to achieve +/-1ct (+/-0.01 semitone) tuning across 10 octaves- well below human ear pitch sensitivity which is around 3-5ct.

All inputs and outputs are ruggedized, protected when signal is connected to the wrong input - able to handle rail to rail voltages +12V..-12V.

All potentiometers are precision Alpha variety, module is made using high quality electronic components, features rubber knobs with soft touch for easy grip and pleasant tactile feedback.

Module is available with and without 1kΩ compensation. Compesation is required when used with pitch CV modules with 1kΩ impedance such as Moog Mother 32, MST '07 Buffered Multiple and others. Doepfer and other new modules have buffered 0kΩ impedance on pitch CV, non compensated version should be used in this case

Revision 2.0: Newer OpAmps and gold plated contacts.

Revision 2.1: Improved Pitch stability, tracking and TZFM precision. Removed octave switch trimmers for easier tuning - instead used precision parts for fixed octave switching accurate within 1ct. Burr-Brown audio opamps on all outputs.

Revision 2.2: octave switch changed from 6 to 8 positions for more modulation options, added startup circuit to prevent VCO lockup on start for those with asymmetric power supplies, modern JFET/CMOS OpAmps - slightly improved accuracy and reduced power consumption, extra components for accurate sine outputs with virtually no offset, high end trimmers for even more accurate pitch tracking.

Power consumption: +12V - 175mA, -12V - 150mA, +5V - 10mA

Module width: 16HP

Module depth: 3.8 cm

Modulation: 1 volt/octave - +5V..-5V or 0..10V

Tuning precision: 10 octaves - +/-1ct (+/-0.01 semitone)

Frequency range: 0.5Hz - 20kHz

Noise level: -90dB

Input impedance: 100kΩ

Output impedance: 1kΩ 0.1%

# listings[].model
3HP Quad Active Mult Splitter Eurorack Module 2.0

# listings[].title
Eurorack 4HP Quad Active Multiple CV Divider 0.1% Precision Buffered Splitter Module

# listings[].shop_name
LFusion Electronics Eurorack Synth Modules and Parts

# listings[].description
New upgraded precision 4HP analog quad buffered signal splitter/multiplier module for 3U Eurorack systems. Offers 4x 1 to 3 exact buffered signal copies with 0.1% precision. Suitable for both audio and CV. Very low noise and distortion, prevents detuning when same pitch CV signal is sent to Oscillator(s) and Filter.

Please note: The module is available in two options - Classic: with 1kΩ source impedance compensation and without the compensation. 1kΩ resistor is "Vintage Standard" used in Moog Mother-32 as well as other classic synth and Eurorack module pitch CV outputs. Modern: many Doepfer and other recent MIDI to CV modules and sequences use 0Ω impedance scheme to output pitch CV and do not need compensation, just accurate buffering. Please check the manual of your MIDI to CV converter to check the value of their output resistor (impedance) and let me know which version of the module should be sent.

If you are planning to use buffer outputs to control Moog and other synths that expect 1kΩ impedance choose outputs of 1kΩ otherwise choose 0Ω, in both cases it will provide 0.1% precision. This can be set up separately for each buffer.

Compact single PCB design. Upgraded version is designed to pass CV voltage to the next buffer if its input is not connected, allows daisy chaining 2x to 6 or 1x to 12 copies. New version also features elongated screw holes and better Burr-Brown audio OpAmps rated with max 0.25mV offset as well as extra parts to allow true 0 ohm impedance.

Power consumption: +12V – 20mA, -12V – 20mA

Module width: 4HP

Module depth: 2.5 cm

Input impedance: 100kΩ

Expected source impedance: 0kΩ or 1kΩ (one of two options upon request)

Output impedance: 0Ω or 1kΩ 0.1% (one of two options upon request)

Noise level: -90dB

Testing: Fully tested before dispatch

# humanized_params
LFusion Electronics Eurorack Synth Modules and Parts