4ms Quad Pingable LFO Eurorack Module Kit (12 HP, Silver Panel)

4ms QPLFO Kit Overview

Designed to be useful in small portable systems that require maximum functionality in minimal space, as well as large systems that need maximum modulation sources, the silver 4ms Quad Pingable LFO Kit is a do-it-yourself compact, playable four-channels each with tap tempo, clock-syncable LFO with variable skew and reset, in Eurorack format.

The QPL features four independent LFOs that can produce a variety of shapes and each channel can easily modulate, trigger, and reset each other for complex and slowly morphing outputs. The Quad Pingable LFO Kit includes all the components needed to complete the module as well as a silver panel.

Full DIY Kit

• Includes all the parts necessary to build a full-featured QPLFO
• Advanced-Level Kit: Soldering proficiency required
• Tools Needed (Not Included):
  • Soldering iron, solder
  • Flush snips
  • Needlenose pliers (for removing a component if you make a mistake)
  • 5/16" and 3/8 socket driver (optional: pliers will work too if you re careful)
  • Multimeter (for reading resistor values if you don t know the resistor color-code chart)

Basic Overview

• Quad pingable LFO frequency is set by time between pulses (pings)
• 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 inbetween
• 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 500 Hz (marginal tracking up to 1 kHz)
• Tap-tempo button is free-running (LFO runs indefinitely), but external clock/ping is autostopping (LFO stops when external clock stops)

Controls and Jacks

• Ping button 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)
• 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
• Ping 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

Skew Knob and CV

Control the waveshape by altering the ratio between rise and fall times

• At 0% Skew (0V of CV), the shape is a plucky near-exponential 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

Advanced Functions

• 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

Eurorack Ready

• 12 HP Eurorack format module
• Maximum Depth: 1.57" (40mm)
• Includes 10- to 16-pin power ribbon cable