Now the thing to remember here is that SysEx does not only deal with MIDI data i.e. the data required by the device to recreate the audio. SysEx can also deal with audio, usually in short pieces of it. This is particularly true is in the case of samplers in that the audio data itself is still bound and transmitted within a SysEx framework. My Roland S-220 works this way as did many other samplers of it's generation. The most important concept with regard to SysEx is to recognise that it is a bundle of data that is transmitted between devices that specifically understand and can interpret what the data means.

System Exclusive means exactly what it suggests, it is transmitted data that is exclusive to a particular system (and its features) defined by a specific manufacturer, thereby preserving their ability to innovate while still being compliant to a broader specification. The two key scenarios where SysEx comes into its own are where two machines that are exactly alike can trade information such as individual parameters, patches or entire patch sets; and computer to machine where the computer's software understands the specific architecture of the synth and can send and receive messages to it.

So why is a specification that is fundamentally 30 years old so important now. The answer lies in the recent clamour for analog synths of old and the inevitable passage of time. As more time goes on machines that began to emerge in the 1980's on the back of the digital and MIDI revolution are increasingly becoming vintage and therefore sought after, while others simply regard them as timeless classics. The challenge however for people acquiring these machines is to understand the way in which individual parameters are addressed.

Contemporary synths today, both hardware and software, predominantly use the Continuous Controller or CC# mechanism to address these parameters whereas synths of a previous generation use a SysEx message that is in the form of hexadecimal notation. This notation allows for 8-bit numbers (0-255) to be represented using two characters. A string of these numbers is sent to the device in order to tell it what to do.

All SysEx messages do have some common elements such as 'I'm a SysEx message', they will also have a unique Manufacturers ID and a Model number and so on. This allows machines that the message is not intended for to ignore it, even machines from the same manufacturer but not the same model. This is critically important so as not to break people's existing MIDI routing and daisy chain setups. The spec allows for the message to be passed THRU to its intended recipient. After this the contents of the message get very specific i.e. 'Exclusive'. So to whet you appetite let's explore a simple example and for this I'm going to use my humble Roland D-110 (because it's simple). We will also assume that we don't care too much what is sending the message, it could be another D-110, a PG-10 controller or a computer based editor / librarian.