Forum Discussion Thread - for comments, corrections, or questions about this article
Since firmware version 87, the SEQ V4 supports the use of two Novation Launchpads as a BLM control surface. Two Launchpads form a 16×8+X BLM, and up to four can be connected to make a full 16×16+X control surface.
The Launchpad BLM is implemented as a feature of the JUCE-based BLM emulator software. The launchpads don't connect to the SEQ directly. Instead, they connect to a computer running the JUCE BLM emulator - the emulator software acts as a translator, converting the BLM Protocol sysex messages into midi signals to light the LEDs on the Launchpad, and translating button presses on the Launchpad into a format the SEQ can understand.
This has been tested with the Novation Launchpad Mini. Presumably, the Launchpad S should work as well, since they're essentially the same controller. The original launchpad hasn't been tested. If you have one, try it and post a comment in the forums to let us know if it works.
Support for button grid controllers other than the launchpad may be possible in the future.
…and you're done!