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    Advanced Level Build    Compact and Playable    4-Channel Tap Tempo, Clock Sync LFO    Variable Skew and Reset    Can Use Channels to Modulate Each Other    Pluck, Triangle, Saw-Up, Saw-Down Shapes    Includes All Kit Components

• 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)

• 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)

• 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

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

• 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

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

Related Questions and Answers

Q: 1. What are the sizes along with any other informaion?

A: These are replacement panels for the Lastolite Triflector kit, B&H # LATL2PSWK. They measure approximately 30 inches per panel.

Q: 2. can the increments for aperture and shutter be set independently? IE can I set 1/2 stop aperture increments then set 1 stop shutter increments?

A: Yes, stop increments for shutter and aperture can be set individually on the Sekonic Speedmaster L-858D-U Light Meter.

Q: 3. Is there an adapter for round flash units like Godox V1?

A: Unfortunately, this kit is limited to standard shoe mount flashes with a rectangular head.

Q: 4. Does the screen light up for night use ?? If so, for how long ?? Jim

A: Yes and can be set for 20-60 seconds.

Q: 5. Is there a color meter option?

A: Yes, this Sekonic color meter is excellent: https://www.bhphotovideo.com/c/product/1436631-REG/sekonic_401_800_c_800_spectomaster_meter.html

Q: 6. Hi The version L-850D - U, (U for USA) can also work in PAL system 25 fps and 1/50 T, or is it only done by the L-850D? BR. Renzo

A: We believe you mean the Sekonic Speedmaster L-858D-U Light Meter B&H # SEL858DU for we were unable to find the the L-850D-U, even on the Sekonic discontinued site. In any event, the L-858-U does do all standard frame rates including 25FPS PAL.

Q: 7. How long does this meter take to boot up? From completely off to completely useable.

A: The start time is about 4 seconds from the time the power button is pressed and held.

Q: 8. Can I buy the magnetic adapter from B&H? Please provide link.

A: Please see attached link for BH #HAHLM600CL • MFR #HL-MODULE-600CLAMP and for B&H # HAHLM360CL MFR # HL-MODULE-360CLAMP 360: https://bhpho.to/3oeaGuS 600: https://bhpho.to/3pN8Scv

Q: 9. Does this have a t-stop mode? When working with cinema lenses that use t stops instead of f stops, how can I use this light meter?

A: F/stops are arithmetically calculated based on the lenses physical size. The amount of light coming through the lens is therefore theoretical. This means two different lenses at f/5.6 could be passing different amounts of light. In the days of movie making film, this caused a great deal of problems for movie printmaking where the density of the image would vary greatly between shots. This would take extra time, effort and money to get a consistent print. To eliminate this problem, the 20th Century Fox camera department in the 1930's developed the T or Transmission stop. What they did is measure the amount of light coming through the lens and then set that as the T/stop. Since glass absorbs light, there is a light loss compared to f/stops. All this to say, there are no T/stop meters; they are all f/stop. Just read the meter, set that number on the T/stop ring and enjoy a consistent, lens to lens, exposure.

Q: 10. Can I use to this on profot A1 series flash and if so do I need to buy an adapter for it?

A: Unfortunately, this kit is not compatible with the Profoto A1. A compatible kit to start with is the Profoto Gel Kit for A1 Flash, BH # PRA1GK along with any gels of your choice. https://bhpho.to/2VVBy69