TWENTIETH- - Synapse Music

250 Timbre and Texture: Electronic
usually included combinations of a variety of oscillators, filters, envelope generators, and
other modules, all designed to work together as part of a single larger unit. Composers created
sounds by using "patch cords" to connect the outputs and inputs of the modules to
create sounds or even full gestures. Smaller units incorporated internal wiring matrices that
allowed for connections to be made with buttons and switches. While the core modules
were similar, different composers were able to create a remarkably wide variety of sounds,
even on the same instrument. Two widely used voltage-controlled synthesizers were the
Moog, used in Wendy Carlos's Switched-on Bach ( 1968), and the Buchla, used in Morton
Subotnick's Silver Apples of the Moon (1967).
A drawback that these modular synthesizers shared with earlier electronic equipment
was that it was often difficult and time-consuming to create and later try to recreate patches.
This led to synthesizers that combined and routed the modules together internally with
simpler buttons and knobs for limited patching and controls. The MiniMoog is a good example
of this type of pre-routed synthesizer, and many software programs available today
emulate its operation. As microprocessors became more common (and affordable) they
were added to synthesizers, making it possible to store and recall these patch configurations
and settings. This allowed composers and performers to recall even complex patches
with "a push of the button."
Microprocessors rapidly became more inexpensive and incredibly more powerful. In
a relatively short time commercial synthesizers became entirely digital-with the synthesizer
becoming a "dedicated" music-making computer- a computer built only to make
music. As personal computers have become even more powerful they have increasingly
taken over synthesis and music-making functions from their "dedicated" predecessors.
D IGITAL SYNTHESIS
Electronic music synthesis has from the beginning made use of anaLog equipment like that
described in the preceding section, but since the late 19705 there has been increasing interest
in digital synthesizers and digital synthesis software running on computers. A basic difference
between the two (analog and digital synthesis) is that an analog device allows an
infinite number of meas urements within its range, whereas digital devices count in a limited
number of steps. For example, the old-fashioned analog watch can theoretically display
the time more accurately than a digital watch, because it is not limited to a fixed number of
increments. With a digital system, measurements that fall between increments must be assigned
the value of a nearby step. The reader can easily see the result of this quantization,
or "rounding" of values by changing the color resolution of a computer monitor while
looking at a photograph. Most computer systems display pictures with millions of colors
(almost seventeen million). Lowering the resolution to "thousands of colors" (around
65,000) makes a somewhat noticeable impact on the picture quality. Setting the resolution
to 256 colors changes the picture quality dramatically. For audio, quantizing creates audible
noise. For CD-quality and higher, quantization noise is rarely a factor. The advantages
of a digital system include iL' smaller size, the greater ease of "patching" the various
components together, and the ability to instantly and accurately recall parameter settings.