Build your own Quad Pingable LFO, with the QPLFO kit.

Check out the videos here and here.

Basic features
• Quad "pingable" LFO's -- frequency is set by time between pulses ("ping")
• Each of the 4 channels is an independent LFO
• Can produce a variety of waveshapes: "Pluck," to ramp-down, to triangle, to ramp-up, and all shapes in between
• Channels can easily modulate, trigger, and reset each other for complex and slowly morphing outputs
• Slowest period is about 71 minutes (0.0002 Hz), fastest speed is about 500Hz (marginal tracking up to 1kHz)
• Tap tempo button is free-running (LFO runs indefinitely), but external clock/Ping is auto-stopping (LFO stops when external clock stops)

Controls and jacks
• Tap tempo button ("Ping") for manually setting the tempo
• Ping jack sets tempo with an external clock (any complex signal can be used as a clock)
• On/mute button enables or mutes the output (latching button)
• Skew knob and CV jack control the waveshape by altering the ratio between rise and fall times
    - At 0% Skew (0V of CV), the shape is a "plucky" near-expo curve
    - At 1% Skew (just over 0V of CV), the shape is ramp-down
    - At 50% Skew (about 5V of CV), the shape is a triangle
    - At 100% Skew (about 10V of CV), the shape is ramp-up
    - Skew knob provides offset to the incoming CV signal, so any range of CV is acceptable
• Reset jack restarts the LFO without changing the tempo (rising edge triggered)

• OUT jack outputs either a 0 to 10V waveshape, or a -5V to +5V waveshape (jumper selectable)
• LED flashes and dims to the signal on the OUT jack
• Tap tempo button flashes to the internal tap-tempo clock or to incoming pulses on the Ping jack
•On/Mute button lights up when channel is On

Advanced
• Ping and Reset inputs use comparators, so any waveshape can be used for triggering (audio waves, complex LFOs, even the QPLFO itself!)
    - Trim-pot on PCB allows for adjustment of comparator threshold value
•  "Fire-on-unmute" jumper per channel:
    - When this optional jumper is installed, pressing the On button to turn the channel on will reset the LFO.
    - If the jumper is not installed (factory default), pressing On will unmute the LFO without resetting (LFO runs in the background when muted)
• Bipolar/Unipolar jumper:
    - Setting jumper to Bipolar makes the outputs -5V to +5V
    - Setting jumper to Unipolar makes the outputs 0V to +10V
    - One jumper controls all four channels
• One-shot mode: Reset jack can be used to trigger a one-shot envelope if the external ping clock is stopped. See manual for detailed discussion
• Floating Reset mode: Holding a high gate on Reset jack allows the waveshape to run freely without automatically re-syncing to the ping clock. A bare cable plugged into the jack causes a high gate
• Connects to other modules using ribbon cables:
    - Outputs can connect to the 4ms VCA Matrix, or the 4ms SISM, the Circuit Abbey Intermix or the Toppobrillo Mixiplexer
    - Normalization of ping jacks can connect to the 4ms Quad Clock Distributor

Power: 89mA @+12V using external +5V (154mA using internal 5V) , 73mA @-12V,

              65mA @+5V with external +5V (0mA using internal +5V)

Width: 12HP

Depth: 40mm

DIY level: medium/advanced. The Do-it-yourself kit includes all the parts necessary to build a fully-featured QPLFO. Building instructions can be downloaded here.

Build your own Rotating Clock Divider, with the RCD kit.

The Rotating Clock Divider (RCD) produces eight divided clock tempos from a single input clock. The divisions range from /1 to /64, including all odd and non-standard divisions such as /3 and /17 and /62. A Rotate CV input re-assigns the division number of each jack, allowing for creative mix-ups and experimentation. A Reset input jack helps to sync/start with an external clock. Check out the video!

Basic Features:
• Divide-by-1 to Divide-by-64, on 8 output jacks
• CV Rotate jack to shift divide-by amount on each jack
• CV Reset jack to reset/re-sync all jacks
• Optional break-out panels to expand functionality (Auto-reset, selectable Divide-by range, Gate/Trigger, Up/Down-counting)

Jacks:
• Clock Input (5V to 15V clock, rising edge triggered), max 3kHz
• CV Rotate (0V to +5V input)
• CV Reset (5V to 15V trigger)
• Divided Clock Outputs (8 jacks):
    - Divide-by-(1+R)
    - Divide-by-(2+R)
    - Divide-by-(3+R)
    - Divide-by-(4+R)
    - Divide-by-(5+R)
    - Divide-by-(6+R)
    - Divide-by-(7+R)
    - Divide-by-(8+R)
    - ...where R is the CV Rotation.
• Selectable Gate/Trigger mode:
• Selectable Divide range up to Divide-by-64:
Two jumper pins on the back can be pre-set with jumpers plugs, or used with (forthcoming) breakout panel.
• Selectable Auto-reset:
Auto-reset will reset the divide counter every 16/24/32 clocks, which keeps the beats more "dance-able" even when using the "weird" clock divisions (3/5/6/7/9/10/11/etc..) Two jumper pins on the back can be pre-set with jumpers plugs, or used with (forthcoming) breakout panel.

Power: 33mA @ +12V / 4mA @ -12V

Width: 4 HP

Depth: 35mm

DIY level: medium. The Do-it-yourself kit includes all the parts necessary to build a fully-featured RCD. Building instructions can be downloaded here.

Build your own Rotating Clock Divider Breakout, with the RCDBO kit. Check out the video here.

Basic Features:
• Gate Counting: Down/Up
• Gate/Trigger mode
• Divide range up to Divide-by-64
• Spread mode: Spread mode causes the output to "spread" evenly amongst the entire max division range (see manual).
• Auto-reset: 16/off

Power: 0mA @ +12V
Width: 4 HP
Depth: 48mm

DIY level: easy. The Do-it-yourself kit includes all the parts necessary to build a fully-featured RCD Breakout. Building instructions can be downloaded here.

Build your own Shuffling Clock Multiplier, with the SCM kit. Check out the video here.

The Shuffling Clock Multiplier (SCM) produces eight multiplied clock tempos from a single input clock, ranging from x1 to x8 (x32 by using the Breakout). Some of the outputs can be shuffled/swung. The amount of shuffle is controlled by a CV Slip jack. A Rotate CV jack re-assigns the multiplication number of each jack. More features of the SCM can be controlled by the SCM Breakout.

Basic Features:
• Multiply-by-1 to Multiply-by-32, on 8 output jacks
• Five Slipped/Shuffled/Skipped clock outputs (S3, S4, S5, S6, S8). Each is based on a multiple of the input clock frequency (x3, x4, x5, x6, and x8, respectively)
• Three steady clock outputs (x1, x2, and x8), which are not effected by Slip/Shuffle/Skip effects
• CV Rotate jack to shift multiply-by amount on all jacks
• CV Slip causes particular beats to land ahead in time
• Connects to the SCM Breakout for controlling more features: Pulse Width, Shuffle pattern, Skip, Re-sync, Mute, and 4x Fast
• ISP header: Connects to in-circuit programmer such as AVR ISP MKII for reprogramming code
• Maximum input frequency 3kHz

Power: 33mA @ +12V, 4mA @ -12V

Width: 4 HP

Depth: 35mm

DIY level: medium. The Do-it-yourself kit includes all the parts necessary to build a fully-featured SCM. Building instructions can be downloaded here.

Build your own SCM Breakout Kit. Check the video about it.

The SCM Breakout is an add-on module for the Shuffling Clock Multiplier. It adds a host of new features for controlling shuffle/swing patterns (Slip, Shuffle, and Skip), as well as Pulse Width, Mute, and 4x Fast. Each feature has a CV jack and manual knob. The Mute and 4x Fast buttons act as inverters of the gate signal on their respective jack, and light up to indicate on/off status.

Basic Features:
• New features for version 2:
    - Mute and 4x Fast are LED buttons
    - Pressing Mute or 4x Fast inverts the signal on the jack
    - Knobs are centered straight up (12:00)
    - Rotate and Slip knobs attenuate the breakout jacks, and the corresponding jacks on the main SCM module are added to this attenuated signal. If nothing is plugged into the Rotate or Slip jaks on the breakout, the knob functions as a manual control (same as it did on version 1).
    - Depth 25mm
    - Power draw maximum 14mA extra from the +12V (no -12V or +5V draw).Power is taken from the main SCM module

• Expands the features of the SCM:
    - CV Shuffle jack and knob selects which beats are slipped by CV Slip (default=every other beat)
    - CV Pulse Width jack and knob controls width of output pulses (default=50%)
    - CV Skip jack and knob omits certain beats in a pattern (default=no skip)
    - Re-sync Trigger input
    - Additional CV Rotate and CV Slip jacks add to main SCM's Rotate and Slip jacks
    - 4x Fast CV Gate jack and switch speeds up multiply-by amounts
    - Mute CV Gate jack and switch stops any more beats from starting

Power: 12mA @ +12V, 0mA @ -12V
Width: 8 HP
Depth: 26mm

DIY level: easy. The Do-it-yourself kit includes all the parts necessary to build a fully-featured SCM Breakout. Building instructions can be downloaded here.

This is not a DIY Module! The Percussion Interface (PI) and PI Expander are a pair of Eurorack modules that generate gates and envelopes from acoustic drums, samplers, drum machines, and virtually any audio source. Please check out this video and that.
Converting microphone, instrument, line and modular signals into CV and clock/gate signals, the PI and PI Expander are suited for synchronizing sequencers or other modules to the rhythm of an audio track or live percussion. The modules can simultaneously be used as a pre-amp for microphones or line-level signals, while generating inverted envelopes useful for side-chaining. The PI module contains all the core functionality and can be used without the Expander to conserve space. The Expander requires the main PI modules and adds three gain stage options, a modular-level audio output jack, a 1/4" (6.35mm) input jack, and envelope attenuation capabilities. The two modules are only sold together, they are not available separately.

Basic Features:
 • Sensitivity knob, Low/Medium/High gain switch, and clipping LED
 • Sustain control to prevent misfires, increase gate length, and control the envelope
 • Non-inverted and inverted envelope outputs, useful for side chaining
 • Four envelope outputs: two attenuated with independent attenuators, and two non-attenuated
 • Envelope following or generation modes
 • Gate output for clocking sequencers or any unit with a clock or trigger input
 • Compatibility with drums, pads, samplers, microphones, piezos, drum machines, etc.
 • 1/8" or 1/4" input jack (6.35mm)

Power: 104mA @+12V, 65mA @-12V
Width: 4HP
Depth: 25mm

This is not a DIY Module!

Build your own Passive Mult kit.

The Passive Mult is a two channel multiple. It can behave as a dual one to three mult, or in a single channel/normalized one to six configuration. Since the device is passive it can also be used as a three to one, or six to one mixer! This module requires no power, so all you have to do is build up and install it in your enclosure with the supplied 3mm screws.

Power: 0mA @ +12V
Width: 2HP
Depth: 40mm

DIY level: easy.  The Do-it-yourself kit includes all the parts necessary to build a fully-featured Passive Multiple. Building instructions can be downloaded here.

Build your own QCD Expander Kit.

• Connects to QCD module with a 16-conductor ribbon cable (included)
• More features are added to each QCD channel:
 - Multi-mode output jack INV OUT mirrors the tempo of main QCD output
 - Mode Switch for each INV OUT jack:
    - Delayed Trigger Mode
    - Inverted Gate Mode
    - Shuffle Mode (delayed + original trigger)
 - PW/Delay knob controls trigger delay time on INV OUT jack (or pulse width in Inverted Gate Mode)
    - Also controls Pulse Width of main QCD OUT jack
    - CV input jack for external control
    - Attenuverter allows for one channel to precisely modulate another channel's delay or pulse width
 - Div/Mult CV attenuator knob
    - Controls how much the signal on the main QCD's Div/Mult CV jack will modulate the tempo
    - Useful for precisely modulating the speed of one channel with another
• Global LED brightness can be adjusted from the front panel


Power: 44mA @ +12V, 30mA @ -12V
Width: 12HP
Depth: 25mm

DIY level: medium/advanced. The Do-it-yourself kit includes all the parts necessary to build a fully-featured QCD Expander. Building instructions can be downloaded here.

Build your own Swash Kit.

The Eurorack Noise Swash is a chaotic random noise-maker and CV generator, generating its own sounds or working as an audio processor. As a stand-alone device it generates unpredictable continuously morphing oscillations on the Audio Output jack, and random CV fluctuations out the dual-direction "Mood CV" jack. A second CV input jack controls the Swash and Noisegate sections with positive and negative CV voltage. An audio input jack allows for distorting an audio signal beyond recognition, or using audio to trigger and modulate the chaos. The Swash knob is a 10-turn Bourns pot for adjusting minor variations. Each Swash has its own peculiarly unique sound. Check the video.

Power: 40mA @ +12V, 0mA @ -12V
Width: 16HP
Depth: 34mm

DIY level: easy/medium. The Do-it-yourself kit includes all the parts necessary to build a fully-featured Swash. Building instructions can be downloaded here.

THIS ONE IS DISCONTINUED

Harmonics are extracted from an on-board oscillator or external audio signal and outputed as audio or clock pulses. The Position knob sets the cut-off frequency, under which all frequencies will be stepped downwards along a harmonic sequence (octaves, 5ths, 3rds, etc) all the way to sub-audible clicking sounds. Thus, a scale or clock signal can be generated from a single tone. Check out this nice video and that.

Two CV inputs and their respective +/- Vary Amount knobs modulate the Position cut-off. The mix of the two CV inputs plus the Position knob is outputted on a CV jack, and another CV output jack provides a steady +10V clock pulse that is jumper-selectable to be a clock division of the audio output (/1, /2, /32, /64, or non-linear division).

Power: 60mA @ +12V, 0mA @ -12V
Width: 16HP
Depth: 12mm

DIY level: easy/medium. The Do-it-yourself kit includes all the parts necessary to build a fully-featured Atoner. Building instructions can be downloaded here.

Build your own Pingable Envelope Generator Kit. Here is a video.

Basic Features:
• Dual "pingable" envelope generator's total envelope time is set by a "ping"
• Tap tempo button or incoming clock sets the ping time
• Envelope time is a multiple or division of the ping time (from /8 to x8) set by Ping Div/Mult knob and CV
• Curve knob and CV control the shape of the output envelope. Various combinations of exponential, linear, logarithmic, and interpolated curves are available for the rise and fall portions. Total envelope time is maintained throughout any curve selection.
• Skew knob and CV control the ratio between rise and fall times without changing total envelope time

Scaling/shifting:
• Scale knob is an attenuating inverter for main envelope output (Maximum 0V to +10V non-inverted, and Minimum -10V to 0V inverted).
• Bi-polar button centers main envelope output around 0V (-5V to +5V output)
• "+5V ENV" jack is a non-scaling output that always produces a 0V to +5V envelope, regardless of Scale and Bi-polar settings
• "OR" jack outputs an analog OR of the two scaled envelope curves. This outputs the highest value from either envelope at any given moment, taking into account the Scale and Bi-polar controls.

Gate outputs:
• End-of-Rise (EOR) gate output goes high when envelope finishes a rise portion, and goes low when envelope begins a rise portion
• End-of-Fall (EOF) gate output goes high when envelope finishes a fall portion, and goes low when envelope begins a fall portion
• Jumper for each channel changes EOR output to a Half-Rise gate output. The Half-Rise jack goes high when 50% of the time of the rise portion has elapsed, and goes low after 50% of the time of the fall portion. Using the Skew parameter, this jack provides a variable phase gate output useful for quadrature effects and clock phase shifting and trigger delay effects. Factory setting is EOR for red channel, Half-Rise for blue channel.

Triggering/cycling:
• Cycle button for each channel forces envelope to self-cycle in sync with the ping clock (LFO mode). Button lights up when in cycle mode.
• "T" jack toggles the state of both channels' Cycle button when a gate is applied
• "QNT" jack for each channel triggers an envelope to start at the next quantized beat, with respect to the divided/multiplied ping clock. Holding a gate high on this jack causes the envelope to repeat.
• "Async" jack for each channel causes an envelope to output immediately (asynchronously). Holding a gate high results in an AR envelope (rise-sustain-fall). If cycle mode is enabled, the envelope will continue to cycle at this new phase with respect to the ping clock. Phase can be reset to being in sync with the ping clock by pressing the cycle button or applying a pulse to the QNT jack.

CV input jacks:
• CV control of Ping Div/Mult, Skew, and Curve using the CV jacks. Respective knobs set the center offset for the applied CV
• CV of 0-10V will modulate the parameter's full range However, a 0-5V CV will modulate the parameter within a very useful range.

Power: 60mA @+12V using external +5V (105mA using internal 5V) , 35mA @-12V,

              60mA @+5V with external +5V (0mA using internal +5V)
Width: 20HP
Depth: 40mm

DIY level: medium/advanced. The Do-it-yourself kit includes all the parts necessary to build a fully-featured PEG. Building instructions can be downloaded here.

Build your own Listen Up Kit.

The Listen Up is a small passive expander for the Listen modules that provides stereo 1/4" (6.35mm) jack inputs and outputs.
There are four 1/4" jacks arrange in Left/Right pairs. The Left jack of each pair can be used as a TRS stereo jack if the Right jack is unpatched.
The Listen Up connects to one or two Listen modules with the included 3-pin cables.

Basic features:
• Four 1/4" (6.35mm) jacks arranged in two stereo pairs.
• Each stereo pair can be connected to the same module or to separate modules.
• Each stereo pair (left/right) is bi-directional (input or output).
• Left In and Left Out jacks are TRS stereo if corresponding Right jack is not unpatched.
• Uses no power.
• Connects directly to host module using 3-pin cables.

Power: 0mA @ +12V
Width: 4HP
Depth: 40mm

DIY level: easy. The Do-it-yourself kit includes all the parts necessary to build a fully-featured RCD Breakout. Building instructions can be downloaded here.