4.0  The MIDI - Hub

In 1990 Scot Gresham — Lancaster was chosen to beta — test the new Opcode Studio 5 MIDI interface which combines the functions of a computer interface, MIDI patchbay with 15 inputs and outputs, processor and synchronizer in a single box. While investigating its capabilities it quickly became clear to him that it could be programmed to function as a MIDI version of the Hub, which would allow faster, more flexible messaging between computer players than our homebuilt RS232 Hub provided. It would also implement the concept of the group on a standard music technology platform, which we hoped would make the our work more open and accessible to other musicians.

The group decided to "upgrade" the Hub. And like electronic musicians everywhere eventually find out, upgrading the system meant either changing the existing music so that it could play on the new instrument, or else creating a new repertoire made specifically for it. We took the latter route. But changing the messaging system also changed the kind of music we made. Working within the MIDI paradigm had its own limitations; in Tim Perkis' words (from the booklet notes to the Hub's 1994 CD release "Wreckin' Ball", also on Artifact), "In certain ways MIDI is inappropriate for our uses, and we use it in a way it was never intended to be used: as a medium of communication between players. MIDI was designed to allow one master — typically a keyboard player or computer serving as a sequence player — to control a complex orchestra of synthesizers, without any interaction with anyone else."

The MIDI — Hub worked as a switchboard, not as common memory. Instead of depositing data (which could be in any custom format) into a place that anyone could read, the MIDI — Hub protocol provided the ability for each player to send any other player a MIDI message tagged with an identifier of who had sent it. No longer was it up to each musician to specifically look at information from other players, but instead information would arrive in each player's MIDI input queue unrequested. Information about current states had to be requested from players, rather than being held on a machine that always contained the latest information. This networking system was more private, enabling person- to- person messaging, but making broadcasting more problematic. To send messages to everyone, a player would need to send the same message out individually addressed to each player. If a player failed to handle the message sent, its information was gone forever. And messages were sent more quickly under the MIDI — Hub, leading to an intensity of data traffic that was new in the music. The MIDI — Hub pieces reflected the nature of this new aspect of the band's network instrumentation.

"The Javanese think of their gamelan orchestras as being one musical instrument with many parts; this is probably also a good way to think of the Hub ensemble, with all its many computers and synthesizers interconnected to form one complex musical instrument. In essence, each piece is a reconfiguration of this network into a new instrument"

— Tim Perkis, "Wreckin' Ball" CD notes

For more information on the MIDI — Hub, see Tim Perkis' article originally written for the Electronic Musician magazine.

Data — flow diagram of the MIDI — Hub.