All genres charts

Notes: The MCFx2 is ALM's state variable 'MCF' filter made double. It features 2 identical classic analog 3 pole state variable filter cores each with Low, High and Band Pass (or Notch) outputs. Direct and voltage control is provided for both filter cut offs and resonance. Switches allow the filters to function as one, with the 'Feed' switch internally routing audio from one filter to the other in series and the 'Link' switch linking the cut off controls for both filter cores. MCFx2 expands on the great sounding MCF filter to offer both serial and parallel functionality for stereo operation, dual peak, tighter slopes and other complex filtering set ups.

FREQUENCY CONTROLS
Sets the base frequency for the filter cut offs. The v/oct and frequency inputs are added to these.

RESONANCE CONTROL
Sets the level of resonant peaks atop the cut off frequencies. The resonance can get particularly aggressive going into self oscillation with the control past 12 o'clock.

OUTPUTS
Each filter output is 3 pole with an 18dB/oct slope.
Low - low pass filter outputs. Passes frequencies below the cut off.
High - high pass filter outputs. Passes frequencies above the cut off.
BP/Notch - band pass or notch filter outputs. Jumpers on the rear of the module select one or the other for each filter.
Passes frequencies within (BP) or outside (Notch) a narrow region around cut off frequency.

LINK BUTTON
Links the left cut off to parallel control both filters. The right controls will now set the max range of the right core. Both filters will track together when the right cut off is fully clockwise.

FEED BUTTON
Routes the output of the left filter core to the input of the right (unless patched), with the desired output filter type selected via jumper at the rear of the module.

FREQ INPUTS AND ATTENUATORS
Control voltage inputs here are combined with knob offsets to set the final cut off. Attenuversion control allows for both attenuation and inversion of the CV. Expects approx. -5V - 5V input.

RES INPUTS AND ATTENUATORS
Attenuated control voltage inputs here are combined with knob offsets to set the final resonance.
Expects approx. -5V - 5V input.

AUDIO INPUT 'In'
Signal inputs to the filter cores for processing.
Input sources may need to be attenuated, filter will drive from hotter input levels.
The Left input is normalised to the right (unless 'Feed' is enabled).

Notes: Collabing with YouTube sensation Andrew Huang, Endorphin.es offer up this impressive multipurpose processor module. Building blocks of stereo filtering, compression, reverb and more offer huge creative potential.

Supplier's Notes:
In collaboration with Andrew Huang, based on his modern music production techniques, Endorphin.es developed a creative audio processor with multiple blocks that can be moved around in order to achieve different flavours for sound design.

Processing unit without fixed structure: intuitively create astonishing and ephemeral timbres, from atmospheric rumbles to heavy or distorted textures.
Creative stereo effect processor with delay, reverb, filter and distortion with quickly explorable routing chain with single button press.
New generation ARM Cortex - M7 processor with 96 kHz 32 bit internal processing.
Lush hall and whooshing reverse reverbs with audio freeze and pre-delay.
Sidechain audio ducking envelope available both internally and externally with additional one knob single band compressor.
Tap delay with maximum delay time up to 2.5 seconds, external clock input with onboard clock divider and 1v/oct time control.
8x oversampled distortion algorithm.
Pre- and post - VCA, tone and volume controls with extra gain.

Power consumption:
135 mA +12V
35 mA -12V
0 mA 5V

Dimensions:
16 HP
26 mm deep with power ribbon cable connected.

Notes: After Later's redesigned take on the classic Mutable Instruments Rings module offers all the distinctive resonant synth sounds you'd expect, from strings to percussion. Great value.

Supplier notes:
This is an exact hardware replica of the Mutable Instruments Rings module.

Notes: FONT is a massive sounding liquid filter- designed to bring you powerful basslines, tons of FM modulation and a clean resonance over your audio path.

It features two simultaneous outputs:
2-pole Low Pass
2-pole Band Pass

It can also work as a sine oscillator, tracking 1V/OCT when the resonance is at its maximum level.

FONT can be used to make basslines, acid patterns thanks to its organic and musically sounding resonance.

Ping it to produce percussion sounds such as, bongos, congas or toms.

Applying a pitch envelope, it really shines as a kick-drum machine!

22 mA +12V
25 mA -12V
0 mA 5V
15 mm deep
O 4.60 (10 Votes) Average Rating

Notes: The compact and complete VCA. Filtering and mixing rolled into one powerful unit. The Dreadbox Eudemonia Filter is an analog wave generator processor. It provides accurate mixing capabilities and features a dual filter in series. The filters are a 24dB resonant Low Pass Filter and an 18dB non-resonant High Pass Filter - these allow you to shape your sound before sending to your output. In order to keep things in line, the exponential VCA has a peak indicator to help you reference your levels.

Power Consumption: 61mA @ +12V , 69mA @ -12V
61 mA +12V
69 mA -12V
35 mm deep
10HP

Notes: The Variable Q VCF (or VCFQ, for short) from Random Source is a skiff-friendly Eurorack adaptation of what is perhaps the most famous Serge filter. It is an effortlessly thick and colorful 12dB/oct multimode filter with ultra-smooth resonance that never ceases to amaze. Amazing tonal variety comes from combining outputs, automating resonance settings via CV, and adding grit using its adjustable-gain input.

Simple filtration is only one of the VCFQ's many uses, however. Its amazing trigger input turns rising-edge pulses into thick analog kicks and toms which roughly track notes thanks to a dedicated 1V/oct input. This module also becomes an ultra-powerful modulator in "Lo" mode, with decaying/syncable LFOs well within grasp using the trigger input, along with free-running oscillation when self-patched. When fed stepped sequences, sample and hold, or other LFOs, the VCFQ can even function as an effective slew limiter. And that's not all: for those lucky enough to own two VCFQs, dual-peak resonance and an ultra-thick 24dB/oct low-pass mode offer some of the most rewarding synth sounds in existence. In short, adding a VCFQ to one's Eurorack system is always worthwhile.

Features

Analog multimode filter designed in collaboration with Serge Tcherepnin
Automatic Gain Compensation and Variable Gain audio inputs
Trigger input
1V/oct and attenuverted frequency CV inputs
Attenuated Q CV input
Low Pass, Hi Pass, Bandpass, and Notch outputs
Hi/Lo range switch
This is the skiff-friendly, SMD version of the Random*Source VCFQ

Under licence from Serge Tcherepnin
Designed for High-end VCAs (THAT2180)
No matching of transistors required
No wiring needed

Dimensions
14 HP
26 mm deep

Current Draw
52 mA +12V
52 mA -12V

Notes: MMF is an analogue, multimode filter with a 12dB per octave slope. Its sonic character swings all the way from classic low pass to squelchy acid lines. Simultaneous outputs of low pass, high pass, and band pass filter types are provided allowing for many variations of the input signal. Whether you're looking for smooth and creamy, or resonant and wild, MMF can go there.

Notes: Module A-124 is a special 12dB multimode filter using the "strange" filter circuit of the "EDP Wasp" (an analog synthesizer with black/yellow case built end of the seventies, manufactured by the UK company "Electronic Dream Plant" with Chris Huggett und Adrian Wagner). This design "abuses" digital inverters as analog operational amplifiers leading to distortions and other "dirty" effects that generate the specific sound of this filter. The filter is equipped with a band pass output and a combined low/notch/high pass output. For this output a control knob defines the relation between low and high pass signal. If both signals appear at the same level (i.e. middle position of the Mix knob) one obtains a notch filter. Otherwise the low or high pass signal predominates. The module does not feature self-oscillation in contrast to most of the other filters of the A-100 system.

Inputs: Audio In, CV In (2x)
Outputs: Bandpass Out, Low/Highpass Mix-Out
Controls: Audio and CV attenuator, Frequency, Resonance, LP/HP Mix

The function and operation of this module is very similar to the module SEM VCF A-106-5. But the sound of both filters is very different! The only functional difference is the position of the sockets and controls, and the function of the controls CV2 (A-124: normal attenuator, A-106-5: polarizer).

- 3U Eurorack module, 8HP wide, 45mm deep
- Current draw 30mA

Notes: Oof. Frap casually serve up one of the best filters we've seen in a long time. Quad multimode circuits with saturation and feedback give you extensive routing options. Delicious.

Supplier's Notes:
cunsa /'cu?nsa/ s.f. [dialect of Modena of uncertain etymology, probably from a Latin *comptiare, derived from comptus, participle of comere 'organize,' 'decorate'] i curing, seasoning (of foods), tanning (of leathers).

Seasoning is crucial for cooking. It is a process that enhances the flavors, glues the ingredients together, and even adds some unexpected kick.

From a gentle refining touch to a shovelful of spice, CUNSA is the perfect seasoning tool for your patches. It can sweeten a sour lead or beef up an insipid bass line, and anything in between.

And, just like a good oil, you can even taste it by itself!

CUNSA is a quadruple analog pingable multimode resonant filter, saturator, mixer, and oscillator.

It is Frap Tools' sound seasoning tool: it can gently even a patch, applying a final touch, or it can set it on fire with a ridiculous amount of spice. It's up to you and your cooking style!

It consists of four multimode resonant filters with a custom saturation and feedback control that you can use independently or in various combinations and roles thanks to a series of seminormalizations.

Four Analogue Resonant Multimode Filters

CUNSA features four state-variable filters that can be used independently or linked and mixed. Each filter provides three behaviors simultaneously: lowpass, bandpass, and highpass. Each behavior has a 12 dB/oct slope, except for the lowpass, which can be either 12 or 24 dB/oct.

Unique 'Character' Circuit for Feedback and Distortion

CUNSA handles feedback and gain staging with extreme control and versatility. Besides the usual Q control that emphasizes the cutoff frequency, the Character circuit defines the amount of soft clipping when the filter overloads. High clipping guarantees a controlled behavior with fat tone and pure resonance, while low or no clipping lets the signal saturate the filter stages and make it scream.

V/oct Tracking and Quadruple Oscillator

Each filter responds to the V/oct signal with excellent tracking. It is thus possible to move the cutoff frequency along with the main melody or make CUNSA resonate with no input and transform it into a multiple oscillator. The V/oct inputs are seminormalled so you can control more filters with the same CV. Easy chords stabs!

Ping and Ring

CUNSA is ideal for percussive and organic tones. The Ping circuit offers a behavior similar to the BRENSO but AC-coupled. Instead of shooting the frequency to the moon with any trig, CUNSA gently responds to different incoming gates with a selectable decay curve. The Ping circuit can thus create natural decay sounds when fed with trigs or smoother envelopes with any other voltage, like a linear integrator with a custom decay.

Besides this, you can also feed the filter's audio input with trigs and make it ring at high Q settings.

Linked or Individual Filtering

The four filters can work independently or arranged in groups through seminormalled inputs and sum outputs. CUNSA can thus be a 4×1, 2×2, or a massive 1×4 filter. Even odd configurations are possible, like 1+2+1 or 3+1. Mono, stereo, or quadraphonic audio is at your fingertips.

Filter and Combo Behaviour

When the filter behavior is set to COMBINED, every control of the cutoff frequency also affects the input VCA, reducing the signal amplitude and saturation as it approaches the lowest range. It can make organic decays with the ping circuit or tame the low range at high Q and Character settings.

Four Seminormalizations for Group Use

Four inputs have a cascaded seminormalization: audio inputs, VCA CV, V/oct, and Ping. Every signal patched to a filter will thus feed also those at its right, making simultaneous use even simpler. To remove a seminormalization, simply patch a dummy cable to the corresponding input.

Analog Mixing Stage and Group Outputs

Every filter output can be routed to an analogue mix bus that sums the four filters and outputs them in three combinations: all, 1+2, and 3+4. These outputs allow for versatile audio processing. Just like we did with FUMANA, we added a gentle shelving EQ for the higher frequencies of the All output to provide additional timbral variety.

CV Inputs with Attenuators

Besides the seminormalled inputs, every filter features additional CV inputs for cutoff frequency, Q, and Character, each with a dedicated attenuverter.

Notes: Variable Pole analogue filter based on Asteroid Op VCF Tech

Model: Millipede Variable Pole VCF
Analogue Filter, Can easily get Brutal tones.

What does this do?

This is an analogue filter that uses two modern equivalent ssm2164 IC's v2164 from cool audio to do it's magic. This particular filter however allows the user to vary the phase of each pole or filter cell. There are four filter cells total. This is similar to the Blue lantern Asteroid Operator Station VCF. The Asteroid Operator Station VCF has 8 Static filter out puts. Those 8 flavors were found by exploring the circuit found on the millipede vcf and internally installing the resistor ratio for that flavor.

On the millipede vcf you are allowed to find more exotic flavors yourself. Operation is easy. You first have all the poles counter clockwise and the three switches set to mute. This will have the filter as a dark Low pass filter. Then you turn on a pole using the switch and turn the know to hear the change. Pole 3 by default is always on, otherwise there would have been no sound if all poles were muted. Having all the poles set clockwise and active easily gets you into brutal sounding tones in a good way.

There is an on board diode limiter circuit to help tame really harsh tones. This is activated by switch.

The audio input has some gain, so you don't always have it fully clockwise. There is also a capacitor selector switch just like my other filters. This modifies the rez peak.

Dimensions
13 HP
32 mm deep

Current Draw
58 mA +12V
56 mA -12V

Depth: 2.5 inches

Notes: A typically comprehensive approach to noise sources from Befaco, featuring five different circuits plus two analogue multimode filters and plenty of CV controls for sculpting the output.

Supplier's Notes:
Noise plethora has three different noise generators:

The first two are identical and are composed of digital algorithms followed by a 12dB analog multimode filter.
Each program has two variables (Named X and Y) addressed by two manual controls and two associated control voltage INs.
Ships with an extensive (and expanding) algorithms library: textures, wave clusters, harsh noises, and glitches.

Generator C has three simultaneous outputs:

White. Flat Response Classic white noise.
Gritty. Granulous texture noise, with voltage-controlled grit quantity.
Filtered. Is the White or Gritty noise followed by a 24dB multimode VCF.

A total of 5 different noise sources in one module!

Dimensions:

14 HP
25 mm deep

Current Draw
110 mA +12V
67 mA -12V
0 mA 5V

Notes: A seriously versatile filter here, much more than meets the eye. Stereo, state-variable, multi-mode design gives you huge control over frequency response and stereo image.

Supplier's Notes:
Zagrzeb is a stereo multimode 4-pole (24dB/oct) state variable voltage-controlled filter (SV VCF). It offers five distinct frequency responses, three of which are available simultaneously. Spread control allows for animation of the stereo image by moving the left and right filter cutoff frequencies in opposite directions. Zagrzeb is designed to sound smooth and clean unless it is overdriven with a hot signal- however, it does not lack character! We believe it will be appreciated by fans of old Japanese synthesizers, but bear in mind that Zagrzeb is not a clone of any existing design. The four-pole state variable structure is a new development and offers unique sonic characteristics. While Zagrzeb is designed for filtering stereo signals (e.g. samples or stereo oscillators like Xaoc Devices Odessa), it can easily handle mono signals and is capable of creating a faux stereo pair thanks to a special phase shifting network at the input.

Dimensions:
8 HP

Current Draw:
70 mA +12V
60 mA -12V
0 mA 5V

Notes: From one of the most iconic names in modular synthesis, the Variable Bandwidth Filter is a unique design, combining two state-variable VCFs with extensive CV control for clean, versatile filtering.

Supplier's Notes:
The Serge Variable Bandwidth Filter (VCF2) is probably the rarest classic filter in the Serge system, offering a unique combination of 2 filters. According to the 1983 Serge catalogue, the Variable Bandwidth VCF (VCF2) "has a band-pass output which can be varied manually or with voltage control. This is a standard response synthesizer VCF, typical to filters used in many studio systems. In the VCF2, two state-variable VCF's are connected in series to produce a total of five outputs. High pass, low pass, two fixed bandwidth outputs, and one variable bandwidth output are available. The outputs are all flat-response (no resonance) so the VCF2 is suitable for processing concrete sounds without introducing resonant coloration to the timbres. Under voltage or manual control, cut-off frequency of the high and low-pass outputs are affected, as well as the center frequency of the two band-pass outputs. Both center frequency and bandwidth are independently controllable on the variable bandwidth output."

Now - for the first time, designed and licenced by Serge - the VCF2 is available as a eurorack module. A new switch has been added which determines if the CV-controls are routed to the first (left), second (right) or both filters, bringing even more sonic options than the original.

Some details of the Random Source Serge VCF2 module:

Original Serge design, under licence and in cooperation with Serge Tcherepnin
Uses for High-end VCAs
Eurorack format (3U), 20 hp
Power consumption: 45mA @ +12V, 45mA @ -12V
Module depth: < 30mm (1.2")

Notes: Module A-121s is a dual multimode filter which can be used for stereo applications as well as for parallel or serial organized dual mono filters. The core is a 12dB multimode filter identical to the modules A-121-2 and A-121-3. The selection of the filter type is continuously from lowpass via notch and highpass to bandpass. We attached great importance to the usability of the manual controls and CV inputs for both stereo and dual mono applications. For the filter parameters frequency (F), resonance (Q) and type (T) common controls and CV inputs as well as single controls and CV inputs are available. For the filter frequency in addition a manual control and CV input for the filter spread (frequency difference or delta F) is available.

Controls:
F: master frequency control for both filters (large knob)
Type 1 / Type 2: filter type panning/morphing L-N-H-B
Link to 1: Toggle switch so that Type 1 also controls type of filter 2 (i.e. simultaneous filter type control for both filters)
SFM1 / SFM2: Single Frequency Modulation controls (polarizers), connected to the corresponding sockets SFM1/SFM2 (socket SFM1 is normalled to a fixed positive voltage, SFM2 is normalled to SFM1, that way the controls SFM1/SFM2 work as frequency controls for each filter provided that no modulation signals are patched to the SFM1/SFM2 sockets)
CFM: common frequency control, controls two VC-polarizers which process the signals connected to the two sockets CFM1/CFM2, CFM2 is normalled to CFM1, that way also the same modulation signal (e.g. an envelope generator) can be used for both filters and the level controlled simultaneously by the CFM control
Delta F: controls the difference between the frequencies of the two filters manually (frequency "spread"), at centre position the frequencies are the same
Delta FM: controls the level of the Delta FM signal (socket), which allows to control the spread between the frequencies also by an external control voltage (e.g. by an LFO or ADSR)
Q: controls the resonance of both filters simultaneously
Level 1 / Level 2: attenuators for the two audio inputs
QM/TM1, QM/TM2: attenuators for the modulation inputs QM/TM1 and QM/TM2

Sockets:
In1 / In2: audio inputs (In2 is normalled to In1)
Out1 / Out2: audio outputs
F: common frequency control input for both filters (~ 1V/oct)
Delta FM: Control voltage for frequency spread, processed by the polarizer Delta FM
SFM1 / SFM2: single frequency modulation inputs, processed by the polarizers SFM1 and SFM2, SFM1 is normalled to a fixed positive voltage, SFM2 is normalled to SFM1#
CFM1 / CFM2: common frequency modulation inputs, processed by the two voltage controlled polarizers controlled by CFM knob, CFM2 is normalled to CFM1
QM/TM1, QM/TM2: the addressing of these sockets/attenuators is defined by internal jumpers. QM means Q modulation (i.e. resonance modulation), TM means filter type modulation (QM1 = resonance modulation filter 1, QM2 = resonance modulation filter 2, TM1 = filter type modulation filter 1, TM2 = filter type modulation filter 2), socket QM/TM1 is normalled to a fixed positive voltage, QM/TM2 is normalled to QM/TM1
A 45 degrees triangle next to a socket means that the switching contact of the socket is normalled to a fixed positive voltage (SFM1, QM/TM1).
A vertical triangle indicates the normalling of two sockets (In1>In2, SFM1>SFM2, CFM1>CFM2, QM/TM1>QM/TM2).

If the filters do not behave as expected please pay attention to these peculiarities:

For the controls SFM1, SFM2, CFM, Delta F and Delta FM the centre position is the neutral position as these are polarizers. If the filter behaves unexpected these controls should be set to centre positions for the time being.

For the controls F, Q, Level 1, Level 2, QM/TM1 und QM/TM2 the fully CCW position is the neutral position as these are standard attenuators. If the filter behaves unexpected at least the controls QM/TM1 and QM/TM2 should be set to fully CCW. Via the normalling of the sockets QM/TM1 and QM/TM2 and the associated controls the filter parameters adjusted by the major controls (e.g. Type 1, Type 2 or Q) may be overwritten.

By means of small circles at the bottom right side of the front panel the user can mark the function of the QM/TM inputs. These assignments are possible:

QM/TM1 controls QM1, QM/TM2 controls QM2, the filter types are not controlled by external CVs
QM/TM1 controls TM1, QM/TM2 controls TM2, the resonances are not controlled by external CVs
QM/TM1 controls QM1 and QM2 simultaneously, QM/TM2 controls TM1 and TM2 simultaneously

Depth: 45mm
HP : 12

Notes: Module A-121s is a dual multimode filter which can be used for stereo applications as well as for parallel or serial organized dual mono filters. The core is a 12dB multimode filter identical to the modules A-121-2 and A-121-3. The selection of the filter type is continuously from lowpass via notch and highpass to bandpass. We attached great importance to the usability of the manual controls and CV inputs for both stereo and dual mono applications. For the filter parameters frequency (F), resonance (Q) and type (T) common controls and CV inputs as well as single controls and CV inputs are available. For the filter frequency in addition a manual control and CV input for the filter spread (frequency difference or delta F) is available.

Controls:
F: master frequency control for both filters (large knob)
Type 1 / Type 2: filter type panning/morphing L-N-H-B
Link to 1: Toggle switch so that Type 1 also controls type of filter 2 (i.e. simultaneous filter type control for both filters)
SFM1 / SFM2: Single Frequency Modulation controls (polarizers), connected to the corresponding sockets SFM1/SFM2 (socket SFM1 is normalled to a fixed positive voltage, SFM2 is normalled to SFM1, that way the controls SFM1/SFM2 work as frequency controls for each filter provided that no modulation signals are patched to the SFM1/SFM2 sockets)
CFM: common frequency control, controls two VC-polarizers which process the signals connected to the two sockets CFM1/CFM2, CFM2 is normalled to CFM1, that way also the same modulation signal (e.g. an envelope generator) can be used for both filters and the level controlled simultaneously by the CFM control
Delta F: controls the difference between the frequencies of the two filters manually (frequency "spread"), at centre position the frequencies are the same
Delta FM: controls the level of the Delta FM signal (socket), which allows to control the spread between the frequencies also by an external control voltage (e.g. by an LFO or ADSR)
Q: controls the resonance of both filters simultaneously
Level 1 / Level 2: attenuators for the two audio inputs
QM/TM1, QM/TM2: attenuators for the modulation inputs QM/TM1 and QM/TM2

Sockets:
In1 / In2: audio inputs (In2 is normalled to In1)
Out1 / Out2: audio outputs
F: common frequency control input for both filters (~ 1V/oct)
Delta FM: Control voltage for frequency spread, processed by the polarizer Delta FM
SFM1 / SFM2: single frequency modulation inputs, processed by the polarizers SFM1 and SFM2, SFM1 is normalled to a fixed positive voltage, SFM2 is normalled to SFM1#
CFM1 / CFM2: common frequency modulation inputs, processed by the two voltage controlled polarizers controlled by CFM knob, CFM2 is normalled to CFM1
QM/TM1, QM/TM2: the addressing of these sockets/attenuators is defined by internal jumpers. QM means Q modulation (i.e. resonance modulation), TM means filter type modulation (QM1 = resonance modulation filter 1, QM2 = resonance modulation filter 2, TM1 = filter type modulation filter 1, TM2 = filter type modulation filter 2), socket QM/TM1 is normalled to a fixed positive voltage, QM/TM2 is normalled to QM/TM1
A 45 degrees triangle next to a socket means that the switching contact of the socket is normalled to a fixed positive voltage (SFM1, QM/TM1).
A vertical triangle indicates the normalling of two sockets (In1>In2, SFM1>SFM2, CFM1>CFM2, QM/TM1>QM/TM2).

If the filters do not behave as expected please pay attention to these peculiarities:

For the controls SFM1, SFM2, CFM, Delta F and Delta FM the centre position is the neutral position as these are polarizers. If the filter behaves unexpected these controls should be set to centre positions for the time being.

For the controls F, Q, Level 1, Level 2, QM/TM1 und QM/TM2 the fully CCW position is the neutral position as these are standard attenuators. If the filter behaves unexpected at least the controls QM/TM1 and QM/TM2 should be set to fully CCW. Via the normalling of the sockets QM/TM1 and QM/TM2 and the associated controls the filter parameters adjusted by the major controls (e.g. Type 1, Type 2 or Q) may be overwritten.

By means of small circles at the bottom right side of the front panel the user can mark the function of the QM/TM inputs. These assignments are possible:
QM/TM1 controls QM1, QM/TM2 controls QM2, the filter types are not controlled by external CVs
QM/TM1 controls TM1, QM/TM2 controls TM2, the resonances are not controlled by external CVs
QM/TM1 controls QM1 and QM2 simultaneously, QM/TM2 controls TM1 and TM2 simultaneously

Notes: Collabing with YouTube sensation Andrew Huang, Endorphin.es offer up this impressive multipurpose processor module. Building blocks of stereo filtering, compression, reverb and more offer huge creative potential.

Supplier's Notes:
In collaboration with Andrew Huang, based on his modern music production techniques, Endorphin.es developed a creative audio processor with multiple blocks that can be moved around in order to achieve different flavours for sound design.

Processing unit without fixed structure: intuitively create astonishing and ephemeral timbres, from atmospheric rumbles to heavy or distorted textures.
Creative stereo effect processor with delay, reverb, filter and distortion with quickly explorable routing chain with single button press.
New generation ARM Cortex - M7 processor with 96 kHz 32 bit internal processing.
Lush hall and whooshing reverse reverbs with audio freeze and pre-delay.
Sidechain audio ducking envelope available both internally and externally with additional one knob single band compressor.
Tap delay with maximum delay time up to 2.5 seconds, external clock input with onboard clock divider and 1v/oct time control.
8x oversampled distortion algorithm.
Pre- and post - VCA, tone and volume controls with extra gain.

Power consumption
135 mA +12V
35 mA -12V
0 mA 5V

Dimensions
16 HP
26 mm deep with power ribbon cable connected.

Notes: The Mankato Filter is a four-pole lowpass filter with positive and negative outputs at every pole, giving you slopes of 6 dB/oct, 12 dB/oct, 18 dB/oct, and 24 dB/oct simultaneously. The negative slope outputs allow you to use the Mankato as a quadrature sine oscillator with 8 available phases. The Mankato will self-resonate from subaudio to superaudio, and responds to one volt per octave through its unattenuated control inputs. When resonating, the 6dB/oct outputs are slightly hotter than the others and can be driven to lightly saturate at full resonance. The signal inputs are DC coupled, which allows you to use the Mankato as a voltage-controlled slew limiter at very low cutoff frequencies.

Notes: A 22hp version of Mutable Instruments Elements. It is functionally equivalent and therefore runs all firmware options and having identical sound characteristics. This version is great compromise between the tight spacing of Atom and full size original, which is a bit large.

Width: 22hp
12V: 130mA
-12V: 10mA

Module power connector can be connected either way on the module side.

Notes: This is an exact hardware replica of the Mutable Instruments Blades module.

This model uses the original "hard-to-find" opamps, but After Later have substituted V2164M with AS2164D. All of After Later's products use AS2164D and there should be no measurable change in behaviour.

Notes: ***B-STOCK: Item refurbished, repaired and in perfect working order.***


The MST Low Pass Filter is a precision analog dual slope output 2 & 4 pole filter. Simultaneous -12 DB and -24 DB outputs with CV control over all parameters. Can be used as a 1V/O sine wave oscillator

Specifications:

Current draw: V+ max 23.5mA, V- max 15.5mA

Width: 6HP Depth: 3.5cm (1.75 in)

Notes: This is an exact hardware replica of the Mutable Instruments Ripples module.

Width: 8hp
12V: 35mA
-12V: 35mA

Notes: ADDAC714 is a dual channel soft clipping module.

Diode based passive clipping acts as a "brick wall" limiter with a fixed knee given by the inherent diode physics. A passive RC low pass circuit adds a 3.3KHz -3db low pass filter which sculpts the overall tone while also adding further character to the effect.

At the top an On/Off [BYPASS] switch routes the signal into the Effect (Up: Active) or to the bottom output gain stage (Down: Bypassed).

The amount of clipping is set by the [GAIN] control, it mostly works as a threshold control for how much clipping will be applied.
As more clipping is applied the signal's amplitude will also decrease, to compensate for this we set up a gain compensation stage to keep the output amplitude balanced across the Gain range.

Symmetry chooses between bipolar clipping or positive clipping, this relates to the harmonics generated, bipolar for odd and even harmonics (up position) and unipolar for odd harmonics only (down position).

At the second stage, an opamp based x2 output gain with a clipping led, which monitors the clipping at the output, and an [Output] control to set the output volume.

Having the top and middle gain stages provides flexibility allowing the user to completely distort the signal on the top stage and tame it's output level with the second stage.

At the bottom, Input jacks for both channels (Left input is normalled into Right input) and output jacks

Tech Specs:
6HP
4 cm deep
40mA +12V
40mA -12V40mA +12V
40mA -12V

Notes: GOBLET is an analogue filter and distortion unit with some added quirks and extra controls.

Why:

To make stuff sound filthy.
To shape the output of an oscillator.
To live interact with the sound during a performance.
To soft sweep the cutoff thanks to the optocouplers logarithmic response.

With:

Simple waves - make them unrecognizable.
Complex waves - shape them into something new.
Percussions - crank the resonance and give an acid twist to a beat.
No input - play with the feedback and the touch controls.

Dimensions:

8 HP
18 mm deep

Current Draw:

45 mA +12V
25 mA -12V

Whichever power connector you use should work fine with the polarity.

Notes: Bleeding Hearts Eurorack Modular Device

(Random Sequencer, Rhythm Generator, Destroyer, and Filter)

The Bleeding Hearts is a device that starves, bit crushes, splatters, and filters audio sources like no other. Feeding a gate signal to the Bleeding Hearts enables a whole new world of strange and random analog-generated movement. Each position of the 8-step sequencer can bleed into each other and interact with the destruction effect, creating gated and filtered splatters, glitches, and crunches that move to the beat of your patch.

Designed and assembled in Seattle, Washington. Includes a limited 1-year warranty, if registered within 30 days of purchase.

20hp, 42mm deep.

Notes: ***B-STOCK: Box opened, but product is in excellent condition and in perfect working order***


Module A-121s is a dual multimode filter which can be used for stereo applications as well as for parallel or serial organized dual mono filters. The core is a 12dB multimode filter identical to the modules A-121-2 and A-121-3. The selection of the filter type is continuously from lowpass via notch and highpass to bandpass. We attached great importance to the usability of the manual controls and CV inputs for both stereo and dual mono applications. For the filter parameters frequency (F), resonance (Q) and type (T) common controls and CV inputs as well as single controls and CV inputs are available. For the filter frequency in addition a manual control and CV input for the filter spread (frequency difference or delta F) is available.

Controls:
F: master frequency control for both filters (large knob)
Type 1 / Type 2: filter type panning/morphing L-N-H-B
Link to 1: Toggle switch so that Type 1 also controls type of filter 2 (i.e. simultaneous filter type control for both filters)
SFM1 / SFM2: Single Frequency Modulation controls (polarizers), connected to the corresponding sockets SFM1/SFM2 (socket SFM1 is normalled to a fixed positive voltage, SFM2 is normalled to SFM1, that way the controls SFM1/SFM2 work as frequency controls for each filter provided that no modulation signals are patched to the SFM1/SFM2 sockets)
CFM: common frequency control, controls two VC-polarizers which process the signals connected to the two sockets CFM1/CFM2, CFM2 is normalled to CFM1, that way also the same modulation signal (e.g. an envelope generator) can be used for both filters and the level controlled simultaneously by the CFM control
Delta F: controls the difference between the frequencies of the two filters manually (frequency "spread"), at centre position the frequencies are the same
Delta FM: controls the level of the Delta FM signal (socket), which allows to control the spread between the frequencies also by an external control voltage (e.g. by an LFO or ADSR)
Q: controls the resonance of both filters simultaneously
Level 1 / Level 2: attenuators for the two audio inputs
QM/TM1, QM/TM2: attenuators for the modulation inputs QM/TM1 and QM/TM2

Sockets:
In1 / In2: audio inputs (In2 is normalled to In1)
Out1 / Out2: audio outputs
F: common frequency control input for both filters (~ 1V/oct)
Delta FM: Control voltage for frequency spread, processed by the polarizer Delta FM
SFM1 / SFM2: single frequency modulation inputs, processed by the polarizers SFM1 and SFM2, SFM1 is normalled to a fixed positive voltage, SFM2 is normalled to SFM1#
CFM1 / CFM2: common frequency modulation inputs, processed by the two voltage controlled polarizers controlled by CFM knob, CFM2 is normalled to CFM1
QM/TM1, QM/TM2: the addressing of these sockets/attenuators is defined by internal jumpers. QM means Q modulation (i.e. resonance modulation), TM means filter type modulation (QM1 = resonance modulation filter 1, QM2 = resonance modulation filter 2, TM1 = filter type modulation filter 1, TM2 = filter type modulation filter 2), socket QM/TM1 is normalled to a fixed positive voltage, QM/TM2 is normalled to QM/TM1
A 45 degrees triangle next to a socket means that the switching contact of the socket is normalled to a fixed positive voltage (SFM1, QM/TM1).
A vertical triangle indicates the normalling of two sockets (In1>In2, SFM1>SFM2, CFM1>CFM2, QM/TM1>QM/TM2).

If the filters do not behave as expected please pay attention to these peculiarities:

For the controls SFM1, SFM2, CFM, Delta F and Delta FM the centre position is the neutral position as these are polarizers. If the filter behaves unexpected these controls should be set to centre positions for the time being.

For the controls F, Q, Level 1, Level 2, QM/TM1 und QM/TM2 the fully CCW position is the neutral position as these are standard attenuators. If the filter behaves unexpected at least the controls QM/TM1 and QM/TM2 should be set to fully CCW. Via the normalling of the sockets QM/TM1 and QM/TM2 and the associated controls the filter parameters adjusted by the major controls (e.g. Type 1, Type 2 or Q) may be overwritten.

By means of small circles at the bottom right side of the front panel the user can mark the function of the QM/TM inputs. These assignments are possible:
QM/TM1 controls QM1, QM/TM2 controls QM2, the filter types are not controlled by external CVs
QM/TM1 controls TM1, QM/TM2 controls TM2, the resonances are not controlled by external CVs
QM/TM1 controls QM1 and QM2 simultaneously, QM/TM2 controls TM1 and TM2 simultaneously

Notes: Three-band isolator with stereo inputs and outputs, splitting the signal into highs, mids and lows then allowing you to control level and frequency via CV for some clever sound sculpting and modulation.

Supplier's Notes:
Katowice is a stereo variable-band isolator that allows the user to manipulate a selected range of frequencies. It is the first module in a series of upcoming Xaoc Devices products designed specifically for processing stereo signals.

Katowice splits the stereo input signal into three bands: low, middle, and high. While the knobs and CV inputs define the center frequency and bandwidth of the mid band, the low and high bands are automatically adjusted so that the sum of all three is a complete signal. All three bands are passed through high quality VCAs and their stereo outputs are available separately for further processing. A stereo mixdown signal is also available.

Katowice may be used as a crossover network, a parametric EQ, DJ-style kill filter, or other band-selective applications, including multiband compression and stereo enhancement.

TECHNICAL DETAILS:
Eurorack synth compatible
10hp, skiff friendly
Current draw: +100mA / -100mA
Reverse power protection

Notes: 6HP Micromodule of Opensource Rings

Notes: Versatile triple multi-mode filter with neat performance options, including individual outputs for the three channels, plenty of independent frequency control, a master shift control and lots of CV options.

Supplier's Notes:
Versatile triple multimode VCF capable of subtle to extreme tone shaping without losing the performance availability.

The three channels have dedicated outputs, as well as a mix output.

Multiple combinations of frequencies drawings are possible.

It was designed to create a movement to the sound thanks to the individual frequencies voltage control inputs.

Each channel is able to sweep through all the frequency spectrum.

A dedicated shift control with attenuverter cv input is able to swap all 3 filtres at the same time.

The Vibrazum shines at high feedback with 24dB slope, the resonance is well compensated and performative, even taking it to the extreme will not go out of control.

It sounds very "creamy" and full of rich harmonics from a gnarly tone-0shaping tool of sonic destruction, vowel robotic sounds, acid basslines, resonant percussive sounds and more...

Simple layout without compromising the wide range of sonic possibilities.

Specs:

Width: 14hp
Depth: Skiff-friendly
Current draw: +12V: <65mA, -12V: <68 mA

Notes: Revised take on the excellent Benjolin dual oscillator and filter from Rob Hordijk, featuring the 'rungler' stepped CV generator and extensive output options.

Supplier's Notes:
Benjolin V2 - Rob Hordijk's latest revision of the classic Benjolin. The core of the Benjolin continues to be two oscillators, the rungler (stepped CV generator), and a multimode filter.

This latest revision adds:

Reworked oscillator and filter sections

All levels are adjusted to eurorack standards

Two different steps modes (8/16 and 127)

Double and single clock rate

Externally clockable

External filter input with blend control

Notes: Popple is an 8hp multimode stereo filter based on the Mutable Instruments Ripples V1 filter section. Popple maintains the buttery smoothness of Ripples filter while giving you two separate audio paths. The audio paths share a resonance, control, a frequency cutoff control, resonance CV input, and a v/oct cutoff CV input. Each channel then has it’s own cutoff CV input with attenuverters (which are normalled to a 2.5V signal).

Popple will also self-oscillate at high resonance settings, when coupled with the v/oct CV control, it can also act as a dual sine wave oscillator.

Notes: nRings

This is a new build of a micro version of Rings from Mutable Instruments. MicroRings, also called NanoRings, retains all the same functionality as a full-size Rings module.

The module is fully assembled, tested, and calibrated. Eurorack power cable is included.

These modules use tall bushing potentiometers to offer a more stable feel.

Notes: Erica Synths Black LPG is our take on Lowpass Gate idea - it's designed from scratch
module featuring 2nd order lowpass VCF (the original Buchla lowpass gate was 1st order
VCF) and VCA combo with distinct resonance circuit on top. Voltage control over VCF cuto
frequency/VCA oset and mode (VCF/VCF+VCA/VCA), as well as built in decay envelope
generator makes it a versatile module for sound shaping in any modular setup.

FEATURES:
Three vactors for 2nd order VCF
VCF/VCF+VCA/VCA modes
Manual and voltage controlled cuto/oset
Manually and voltage controlled mode selection
Manually resonance depth control
Resonance overdrive switch
Built in decay envelope generator
Manually and voltage controlled decay time
Envelope CV output
Ski-friendly design

SPECS:
Audio output amplitude 10Vptp
CV range (full span) -5V - +5V
Max Decay time 4''
Panel width 10HP
Module depth 35mm
Power consumption 44mA@+12V, 45mA@-12V

Notes: The Dystopia is ideal for complex patches where sound can be used to thicken the sound or filter out frequencies. It features a noise generator which can provide white, white to pink, white to blue, scatter, digital, pitch types of noise. The digital noise is brilliant as it can be used as a random gate generator. The bit crusher stage can range from one second up to 8kHz - meaning you can obtain really thick distortions - ideal for a range of styles of music. You can reference all the signals through the four LEDs too - which help you determine the level at which the module is pumping out the noise sources.

Noise Generator (white, white to pink, white to blue, scatter, digital, pitch)
Bit Crusher with range from 1sec up to 8kHz
Digital Noise can also be used as a Random Gate Generator
Dual Filter (parallel) 12dB Low Pass and High Pass Filter
When you insert a signal to the External In, the Internal Noise generator is cancelled and the External Signal is in process
LED indicator for all controls to illustrate the current CV Sum

56 mA +12V
67 mA -12V
35 mm deep
10HP

Notes: The Beautifier is a flexible OTA based filter, featuring a lowpass/bandpass switch and a selectable slope of 24db and 12dB. Two attenuated CV inputs for frequency cut-off and resonance. The filter self-oscillates at a given point and can be driven quite hard if you crank up the gain. All in all, a versatile analogue workhorse with a lot of character; from smooth and creamy to quite raw and screamy.

47 mA +12V
19 mA -12V
0 mA 5V
26 mm deep

Notes: Analogue goodness awaits with the four-pole Low Pass Filter. Thanks to CV control over resonance and frequency, the Low Pass Filter can go from squelching leads to dynamic sweeps in an instant. In addition, 1V/Oct tracking allows it to double as a musical sine wave oscillator. Bring analog warmth to your system today in a compact, yet stand out package.

Tech Specs:
Width: 14HP
Depth: 38mm
Front Panel: Intellijel format, Pulp Logic replacement panels available here.

Notes: Analogue goodness awaits with the four-pole Low Pass Filter. Thanks to CV control over resonance and frequency, the Low Pass Filter can go from squelching leads to dynamic sweeps in an instant. In addition, 1V/Oct tracking allows it to double as a musical sine wave oscillator. Bring analog warmth to your system today in a compact, yet stand out package.

Tech Specs:
Width: 14HP
Depth: 38mm
Front Panel: Intellijel format, Pulp Logic replacement panels available here.

Notes: Erica Synths Black Dual VCF is a dual multimode filter with CV control over cutoff and resonance for serious modular patches.

At the core of this VCF is a highly stable, custom multimode VCF chip AS3320 (produced in Riga, btw). This module can be used as two independent VCFs with simultaneous HP, BP and LP outputs, controls can be linked to stereo application and both VCFs can be chained in series or parallel to the summing output for ultimate modulations. Bonus feature - the 16 band spectrum analyser gives you visual feedback on what happens on summing output.

Technical specifications:

Audio output amplitude: 10 Vptp
CV input (full sweep): 10 Vptp
Panel width: 18HP
Module depth: 35mm
Power consumption: 40mA@+12V, 36mA@-12V

Notes: Lovely little mono filter module in a compact desktop format. Based on the classic Prophet 5 filter, ideal for processing synths and signals, hooking up to Eurorack or other Hungry Robot modules.

Supplier's Notes:

The Hungry Robot VCF is an all analog, 4-pole low pass filter with a self-oscillating resonance control. It is a close replication of the filter circuit found on the famous Prophet 5. It uses a HM2040 which is a high quality, faithful replication of the original SSM2040 chip. This resonant filter has a beautiful tonal quality. The over-sized knobs provide a satisfying tactile response. The cutoff frequency can be controlled by external control voltage. It has a built-in attenuator and invert switch for the incoming CV. CV input does not track at 1V/Oct, but is scaled to act as a VCA when a 5V signal is applied to CV input. As with all Hungry Robot "Modular Boxes" the VCF can be powered by a simple 9V DC, Negative Center power supply.

KNOBS
-FREQUENCY: Sweeps the cutoff frequency of the filter.
-CV: Attenuator for incoming CV input.
-RESONANCE: Sets resonance of filter. Small volume drop is to be expected. Will self-oscillate at higher settings.

SWITCHES
-INVERT: Inverts the incoming CV input. Toggle to the right to invert incoming CV

PATCH POINTS
-IN: Patch Audio Signal In
-CV: CV input for Frequency. Allows for CV control of this parameter.
-OUT: Patch Audio Signal Out

Dimensions: 4.7" x 2.6" x 1.5"
Power: 9V DC - Negative Center - 2.1mm Barrel

Notes: The famous MS 20 filter for AE modular!

This adaptation of the filter used first in Korg's MS-20 synth for AE modular offers control knobs for cutoff frequency, resonance and CV attenuator. Two signal inputs for different signal levels control the "drive" of the module. Compared to the wasp filter this filter has a significant self resonance and also a very quick response to changes in the cutoff frequency.

The filter type is switchable between lowpass and highpass (LP/HP switch).

Notes: The ADDAC603 VC Triple Bandpass Filter provides three channels of bandpass filters, fantastic for sculpting complex sounds. Each of the channels feature a gain/distortion control with switch to select between x3 or x100 gain, which can cause the input signals to distort, adding another layer of harmonic interest.

The inputs are cascaded together to allow for one source to be filtered three different ways - or each filter can be used independently. The three filters also feature controls for frequency, which sets the cutoff point; width, which sets the width of the band that is being filtered; feedback, which at high settings causes the filter to self-oscillate, and level control, which sets the amplitude of the output. Frequency, bandwidth, and output level each have CV inputs with attenuverters.

A switch sets whether the filter is 24 dB or 12dB per octave. There are individual outputs with phase switch, plus a mix output and dry/wet output with adjustable control for mix balance. This module provides a wide variety of filtering options to add complex tonal shaping to your rack.

Tech Specs:

22HP
3.5 cm deep
250mA +12V
250mA -12V

Notes: This module was developed upon the Tubaz Filter which was released in 2014 by Gotharman but is currently no longer in production. We loved the original module so much that we officially licensed it's circuit and expanded it to feature several new functionalities.

Here's a paragraph from Gotharman regarding the original design:
"I designed it with the purpose of adding crunch, edge and distortion to my eurorack system. It is not an ideal bandpass filter, that cuts off all frequencies above and below the center frequency.
Because of its high drive, there are, in most cases, some bleedthrough of the harmonics, that should have been cut off. You might consider calling it a "Band Add" filter. The main purpose of it, was to add edge, not to be a perfect bandpass filter."

While everything he mentions is still true we believe he was being modest, It's a dirty, gritty, growling and whining monster which promises you some of the most peculiar filter sounds you'll ever hear.
However do not classify it as a "weird" distortion unit just yet because besides this hairy character it can be easily tamed (using lower volume levels) and then, with some care and intention from the user, it will transforrm itself showing it's feline purrrrr and cuddle sweet and caring, or like any good mut, showing up at night all happy, wet and dirty from a full dog's day and will lay down at your feet while wiggling it's tail howling as yawning just happy to be back home.

As such, standard volume principles do not quite apply to these units, the Audio Levels will go up to x2 amplification, Drive will go up to x11 and master outs go up to x2. The combination of these will cover all diferent qualities it can present. Overall sound can be distorted pre-Tube (raising input levels), in Tube (raising drive) or post-Tube (raising Out levels).
Higher Inputs and Drive will always be gritty, lower Inputs and Drive volumes together with higher Output levels will make the overall behaviour more mellow and closer to what a typical filter would behave like.

No standard expectations should be considered when acquiring these units, all of the tubes were built in the 70's and were bought from various sources, we always kept the premise that no tube was a bad tube (unless not really workinng) so due to each specific characteristics no module will sound exactly the same, making each unit particularly unique. This uniqueness will be particularly evident on their resonance/self-oscilating timbre as well as in their own microphonic qualities.

Regarding power and current draw, the module is designed using a low power tube, so it won't starve your eurorack power supply.

Tech Specs:
12HP
3.5cm deep
90mA +12V
60mA -12V

Notes: Genuine EMS synthi filter, with redesigned faceplate!

This legendary filter can be switched between pre1974 and post 1974 filter type and response. For the first time response can be voltage controlled which was designed on the circuit board but not available on the matrix. This module is made under license from EMS. The only officially licensed remake of the EMS diode lowpass filter used in the VCS3 and AKS synths. It´s a faithful recreation of the original circuit, featuring some modifications that are also done on vintage EMS equipment, like a switchable faster CV response option for very quick modulations. Another switch determines if the filter has 18dB/oct slope as used by EMS pre-1974 or 24dB. The cutoff frequency and also the resonance are voltage controllable. Signal inputs and outputs have level controls.

Notes: The Ar Merc'het Brao module is comprised of two filters and two overdrives.

As usual at Touellskouarn it has a Breton name: Ar Merc'het Brao means "The pretty girls".

It can be used with a stereo signal or with two mono signals. The module is modular as well as guitar friendly.

The filters are resonant with a slope of -12dB. A switch allows to switch each filter from LowPass to HighPass. The filter cut-offs are voltage controlled thanks to dedicated CV inputs. Additionally, the Ar Merc'het Brao features global controls for cut-off and resonance.

Both overdrive sections offer the classic and well known TouellSkouarn distortion sound.

Notes: Tone is a quad, voltage controlled filter with low pass and band pass outputs. Its four channel architecture enables the intuitive patching of shimmering, polyphonic textures. The 24dB slope provides a warm, buttery character. Self oscillation allows each channel to double as a sine wave oscillator with v/oct tracking across four octaves. Cascade OTA topology. A perfect match for the Chord.

Notes: Module A-196 contains a so-called phase locked loop (PLL). The basic PLL system is shown in the sketch at the bottom of this page. A PLL consists of three parts: voltage-controlled oscillator (VCO), phase comparator (PC), and low-pass filter (LPF). All parts are normally connected to form a closed-loop frequency-feedback system.

This is how a PLL works: The output of the internal VCO (linear CV control, rectangle output) is compared with an external signal (e.g. the rectangle output of a A-110 VCO) in the so-called phase comparator (PC). The output of the phase comparator is a digital signal (low/high/tristate) that indicates if the frequency resp. phase difference of the two input signals is negative, zero or positive. The output of the phase comparator is processed by a low pass filter (LPF) to generate a smooth voltage that is used to control the frequency of the internal VCO. The 3 units VCO, PC and LPF form a feedback loop that works like this: The control voltage (output of the LPF) increases as long as the external frequency is higher than the frequency of the internal VCO und stops increasing when both frequencies become identical. The control voltage decreases as long as the external frequency is lower than the frequency of the internal VCO und stops decreasing when both frequencies become identical.

But there are some stumbling blocks: Different types of phase comparators with advantages and disadvantages can be made. Some phase comparators e.g. even lock at harmonics, i.e. if the two frequencies to be compared are integer multiples. But for some applications this can be used to create interesting effects. The A-196 contains 3 different types of phase comparators: PC1 is a simple exclusive OR, that even locks at harmonics. PC2 is a so-called RS flipflop and PC3 a more complex digital memory network. The user can select one of the three phase comparators with a 3-position switch. When PC2 is used a LED displays the "locked" state, i.e. when the frequency of the internal VCO is identical to the external frequency.

Special attention has to be directed to the frequency of the LPF. To obtain a smooth control voltage for the VCO the frequency of the LPF has to be much smaller than the lowest frequency of the internal or external audio signal. Otherwise the frequency of the internal VCO will jitter or wobble around the correct frequency. But for special effects this frequency jitter can be used intentionally. Example: frequencies in the range 50Hz...1kHz have to be processed with the PLL. Therefore the frequency of the LPF has to be about 10Hz or even less. Such a low frequency of the LPF causes a noticeable slew of the internal VCO. When the frequency of the external signal jumps e.g. between 500Hz and 1kHz it takes about 0.1 second until the internal VCO reaches the new frequency (like portamento). So one has to find a compromise between frequency jitter and portamento. But these remarks are valid only for the "ideal" working PLL. As the A-196 is used in a musical environment the "problems" and disadvantages with jitter and slew time lead to additional musical applications like portamento effects, wobbling frequencies or harmonic locking according to the type of frequency comparator and time constant of the PLL low pass filter. Instead of the internal manually controlled low pass filter the voltage controlled slew limiter A-171 can be used to obtain voltage control of this parameter. Normal audio filters (e.g. A-120, A-121) cannot be used for this job as the minimum frequency is to high (down to a few Hz or even less necessary) and the signal has to be DC coupled due to the low frequencies. Audio filters are normally AC coupled.

Another very important application of a PLL is frequency multiplication in combination with an external frequency divider. For this the output of the PLL-VCO is processed through an external frequency divider (e.g. A-163, A-160, A-161, A-115) before it is fed to In1 of the phase comparator. In this case the frequency of the PLL-VCO will be a multiple of the master frequency. E.g. if the A-163 is used and adjusted to dividing factor 5 the frequency of the PLL-VCO will be 5 times the frequency of the master VCO. Consequently, frequency division (A-163) leads to frequency multiplication with the PLL circuit. In combination with the PLL low pass frequency several effects can be realized (frequency multiplication with portamento or wobbling). The frequency multiplication can even be used to drive a graphic VCO. If your graphic VCO e.g. has 8 steps (e.g. A-155) and you use a frequency divider with factor 8 in the PLL feedback the output of the graphic VCO has the same frequency as the master VCO. Another application is the generation of pseudo-harmonics (not real harmonics as only rectangle waves are available) or clock generation for switched-capacitor filters.

Notes: Belgian analogue innovators Joranalogue serve up an ultra-versatile filter module. Multimode flexibility meets self-oscillation for added sonic versatility. A hell of a lot of filter for the money.

Supplier's notes:
Representing the cutting edge in modular analogue voltage controlled filter (VCF) design, Filter 8 offers more possibilities and higher fidelity in 12 HP than ever before.

Starting from the classic OTA-style 4-pole cascaded lowpass (LP) topology, Filter 8 features separate LP outputs, each with their own character. Additional filter responses are achieved by pole mixing: 1-pole highpass, a special band boost and notch response, phase shifter and 4-pole bandpass. All outputs are available simultaneously.

Key to Filter 8's performance is the innovative resonant feedback circuit. By increasing the resonance, all outputs will resonate at the filter frequency, without any low frequency response loss. At higher resonance levels, self-oscillation is achieved, turning the module into an excellent 8-phase sine wave voltage controlled oscillator (VCO) with temperature and switchable gain compensation, low distortion, constant amplitude and accurate frequency tracking over at least 5 octaves. At sub-audio frequencies, Filter 8 can function as an 8-output voltage controlled slew modifier or 8-phase low frequency oscillator (LFO).

Simultaneous exponential and linear frequency modulation is possible, for classic FM tones or chaotic modulation. A hold feature is also provided, 'freezing' the output voltages manually or under gate control. This is useful for halting modulations, or as a sync-like effect at audio frequencies. The dedicated 'ping' input allows you to easily create crisp percussive sounds with different timbres.

While rooted in the legacy of classic synthesisers, Filter 8 provides a new approach to musical signal generators and modifiers: instead of simply a VCF, VCO, slew modifier or VCLFO, a single analogue module can now be any of those, and anything in between.

Notes: Welcome to the Forbidden Planet, an all analogue multi-mode filter design influenced by the 1975 Steiner-Parker Synthacon model. Control the Forbidden Planet manually or through CV and take the sound of your Eurorack into new orbits.

Forbidden Planet has three filter input jacks: High Pass, Low Pass and Band Pass. The High Pass section is this module's signature sound - a crisp sharp-cut with no residue, designed to add High Pass filtering capability to Tiptop Audio's wide range of Eurorack modules. Send a throbbing kick drum through the High Pass section and filter out the rumbling lows while maintaining the pulse of the beat. The Bandpass is clear and useful in isolating a pie-slice-range-of-frequencies while cutting off the low and highs, great for accurate sound design or sculpting audio into that sweet spot. The Low Pass is an airy classic 12db two-pole analogue slope ideal for monophonic synth patches and filtering down to the essential low-end bass we all love.

The Forbidden Planet Resonance utilizes an internal feedback path which can sound smooth or aggressive depending on the knob setting. At a low setting, it emphasizes the cut-off harmonics, at middle settings it begins to self-oscillate, and towards maximum setting it forms interesting tones and all sorts of chopped grainy bits of self-oscillation perfect for entering into a sci-fi world.

The Forbidden Planet is an impressive multi-mode analogue filter which adds a broader filter spectrum to the Tiptop Audio modular family and unlocks forbidden creative possibilities in a small package.

Notes: Erica Pico VCF1, is a younger brother of Erica Black Polivoks VCF, designed on the similar topology using rare Russian op amps. As result you get a filter great for acid bass lines, screaming resonance sweeps and deep wobbles.

Features:
- Lowpass and bandpass modes
- Self oscillation
- Rare russian opamps used
- Input protection against overvoltage

Dimensions
3 HP
35 mm deep

Current Draw
12 mA +12V
11 mA -12V

Notes: Module A-103 is a voltage controlled low pass filter with 18dB/octave slope. The circuit is based on a modified transistor ladder (Moog ladder) and is a reproduction of the legendary TB303 filter.

As for the rest the A-103 is identical to the A-120 Moog low pass filter (same controls, inputs/outputs) only the filter sound is different.

Notes: There is almost no modular system without at least one filter-module. You can look at them as the stars within the giant Eurorack-jungle. twinVCFilter is such a star as well. A dual filter module with flexible routing and excellent audio properties. It covers a huge range of different applications without the slightest effort.

Features and Routing:

Each filter section of twinVCFilter works as low- or highpass-filter with a slope of 12 dB/octave or as bandpass-filter with 6 db/octave. Signals can be directed in three ways through the module:

- Serial: The incoming signal passes both filter sections in a row.
- Dual: The filter sections act completely separated of each other. As if they were two individual filter modules.
- Parallel: The incoming signal passes both filters at the same time.

With these routings you can i.e. generate bandpasses or notches with variable slopes and different resonance settings or doubling the filter's slope. These are the more obvious combinations but there is a lot more to discover.

The convenient link-feature allows to couple cutoff- and resonance of both filter sections for straightforward stereo use in dual mode.

Mix section:

The flexible signal-routing is supplemented by the mix-section. Here you can crossfade both filter sections manually or by control voltages. Seamless movements from low- to highpass-filter, is as easy as crossfading from half to doubled slope. Of course you can mix two completely individual signals or toggle between them by using a rectangle-LFO-modulation.

Resonance:

Resonance is a key factor in the context of sound-shaping and sound-generation using a filter. Therefore we carefully trimmed twinVCFilter's resonance to be as musically and stable as possible. You can apply subtle frequency-dependent emphasis to signals and tear them up to self-oscillation. The latter generates a solid sine-wave which is an excellent base for percussive sounds. Possible cross-modulations significantly enhance the sound-generator features. By the way: If you are missing a vibrato-LFO in a patch, twinVCFilter can do the job.

twinVCFilter offers a huge set of features to form impressive soundscapes. It can take subtle influence to signals or massively truncate frequencies. It leaves nothing to be desired. Despite, for those who need additional possibilities we especially designed the tVCF-Extension module.