Digital Sound & Music: Concepts, Applications, & Science, Chapter 6, last updated 6/25/2013
sequencer program goes to the input of the software object, and the output of the software object
goes to the input of the MIDI synthesis program. The software object functions as a virtual wire
between the sequencer and synthesizer. The audio signal output by the soft synth can be routed
directly to a physical audio output on your hardware audio interface, to a separate audio
recording program, or back into the sequencer program to be stored as sampled audio data. This
configuration is diagrammed in Option 4 of Figure 6.28.
An example of this virtual wire strategy is the Rewire technology developed by
Propellerhead and used with its sampler/synthesizer program, Reason. Figure 6.36 shows how a
track in Sonar can be rewired to connect to a sampler in Reason. The track labeled “MIDI to
Reason” has the MIDI controller as its input and Reason as its output. The NN-XT sampler in
Reason translates the MIDI commands into digital audio and sends the audio back to the track
labeled “Reason to audio.” This track sends the audio output to the sound card.
Figure 6.37 Rewiring between Sonar and Reason
Other virtual wiring technologies are available. Soundflower is another program for
Mac OS X developed by Cycling ’74 that creates virtual audio wires that can be routed between
programs. CoreMIDI Virtual Ports are integrated into Apple’s CoreMIDI framework on Mac
OS X. A similar technology called MIDI Yoke (developed by a third party) works in the
Windows operating systems. Jack is an open source tool that runs on Windows, Mac OS X, and
various UNIX platforms to create virtual MIDI and audio objects.
Creating Your Own Synthesizer Sounds 6.2.2
Section 6.1.8 covered the various components of a synthesizer. Now that you’ve read about the
common objects and parameters available on a synthesizer you should have an idea of what can
be done with one. So how do you know which knobs to turn and when? There’s not an easy