Good question. The Arturia MiniBrute manual (http://downloads.arturia.net/products/minibrute/manual/MINIBRUTE_Manual_EN.pdf) provides very little information on its MIDI handling capabilities, so it may be worth contacting Arturia for a proper MIDI implementation chart. For now I can give you some general advice.
First, you'll need to connect the Seaboard to the MiniBrute. It looks like the MiniBrute's USB port is for connection with a computer only, in which case you'll want to use something like the Kenton USB MIDI Host to convert from the Seaboard's USB to a 5-pin MIDI cable. You'll then connect the 5-pin MIDI cable to the MiniBrute's MIDI In.
It's not clear from the MiniBrute manual what MIDI messages it responds to, but here are the 5 dimensions of touch and their corresponding MIDI messages:
It looks like the MiniBrute may respond to CC 1 (mod wheel) messages, so to use Slide you could change the Slide CC to CC 1 in ROLI Dashboard (bundled with the Seaboard). It's unlikely that the MiniBrute responds to note-off (release) velocity, while it's not clear from the manual whether it responds to velocity, pitch bend, and aftertouch messages from MIDI controllers. For more details I'd recommend contacting Arturia.
Thanks, and did I understand correctly in a user comment somewhere that I would also need to purchase additional software to what comes with the Seabord Block to be able to utilize the 5 dimensions of touch whether with the minibrute or ios synths.
And if not, what is the difference between the software that comes with the Seabord Block and the Seabord Rise.
The Seaboard Block comes with ROLI Dashboard (which allows you to fully configure your Seaboard Block's MIDI settings and response to the five dimensions of touch) and Equator Player (a simplified version of our custom Equator synthesizer). You won't need to download additional software in order to set up your Seaboard Block with third-party apps or hardware synths, as you'll be able to do this with ROLI Dashboard. This article describes the differences between the Seaboard Block and the Seaboard RISE, including the software bundled with each.
Has anyone tried to control the Minibrute with the Seabord?
And if it does work, would I need to buy additional software to have the full expressiveness?