what is it:
a MIDI-enabled software recreation of the hardware Klee step sequencer - developed with the input of the sequencer's creators!

New version 2.3 now available!
(see Version History in Documentation for details)

what are its features:
Includes virtually all major functions from the hardware Klee, and adds many new ones. New features in version 2.3 =

• VST instrument hosting, and now VST3 and AU as well (AU is Mac only)
• Now entirely a 64-bit application
• Intelligently constrain output notes to scale (using Modal Object Library) - now with new pentatonic option
• ReWire audio slave support
• Output chord based on active root note - up to 6 notes in chord, plus root note
• New Pat Load option – specify to automatically load bit pattern or not after preset load
• External pattern load via MIDI or audio input triggers
• External MIDI controllers support via MIDI CC messages, with MIDI learn
• Group A - Group B output
• Convert active LEDs to active switches, for Groups A, B, or A and B
• Reverse sequence direction
• Built-in clock divide capability, now with additional options
• MIDI output to any hardware or software synths
• Internal or MIDI clock control
• 18 preset slots for instant recall of parameters (increased from 10)
• Presets can be saved to and loaded from disk
• Synchronous load - loading of pattern happens on clock pulses, and not in between
• Load on Play feature to allow for loading of pattern each time clock started
• MIDI-controllable baseline note
• Custom definable note range allows for alternative scales
• Basic Dark Mode support on Mac Mojave (10.14)

let me see it:
click thumbnail above for screenshot. Videos below! (click YouTube logo to view larger)

Controlling two Mutable Instruments synths with v2:

External MIDI control feature in v2:
Scale & Chord features in v2:
Pulse Width, Direction and External Load features in v2:
Demo of v1:

Also, check out these video examples of what a hardware Klee can do!

i want to learn more:
read the full documentation (pdf, 1.5 MB), or ask questions in our forum
what do i need to use it:

Mac OS X 10.11.6 - 10.14.x, Intel only, 64-bit plugin hosting only

Windows 7, 8 and 10, 64-bit only, 64-bit plugin hosting only
i want to try it:
have fun with the free Demo Version (differences from paid version: no presets, no scale or chord functions, only one VST, and will time out after 20 minutes)
i want to buy it:
$40 USD
PayPal only, no returns -- please try the demo first to see if you like it.
Once we receive notification from PayPal of your payment, we will e-mail you secure download details within a maximum of 72 hours, and usually within less than 24 hours. You will not receive any software or documentation via postal mail, only an electronic download.
who made it:
Dan Nigrin & Defective Records Software
what made it:
created using Cycling '74 technology
i have a question:
please ask in our forum
any other cool stuff:
go take a look
  © 2009-2019 Dan Nigrin & Defective Records Software, All Rights Reserved
who's using it and what they're saying:

Computer Music Magazine (UK)
July 2011 - Step by step tutorial on using the software Klee


Scott Stites
(creator of the Klee sequencer)
Scott Stites Birth of a Synth
"Dan Nigrin's software Klee has taken the Klee Sequencer to where no hardware version could ever go. He's both made it more accessible and expanded it in directions I never would have imagined."


Synthesizer Magazin
(Germany - Issue 28, Sept 2011)
Synthesizer Magazin
Read the M-185 and Klee reviews (in German)


Darwin Grosse
(Cycling '74, host of Art + Music + Technology podcast
Darwin Grosse
"...I'm sitting in my living room with a Joker-like grin on my face, creating some crazy-ass sequences. You (and, by extension, Scott) have done some wonderful work here."

cEvin Key
(Skinny Puppy, Cyberaktif, Tear Garden, Doubting Thomas, etc...)
"Thanks! Very nice work. I have a real [hardware] Klee as well. And this one is much easier to operate!"


Olivier Gillet
(founder of Mutable Instruments, creator of the Shruthi-1 synth)
Mutable Instrument logo
"I thought the patterns produced by the Shruthi "warp" features were unpredictable... and then I tried this thing."


Bill Manganaro
(aka State Machine,; sMs Audio Electronics, member Klee hardware prototype team, supplier of hardware Klee parts kits & build services)
sMs Audio Electronics logo
"Expand, evolve, that's what electronic music creation is about for me. Now I have my hardware Klee control my analog gear, and my software Klee control my computer-based synthesizers... Now I can mold my sounds on the go! Brilliant piece of kit."