So far
we have seen exactly what granular synthesis consists of, how grains can
be created, and combined with other grains, the thought process that led
to granular synthesis, and the compositions that have been created using
granular synthesis. This now leads us to another area. Doing our own work
with granular synthesis.
There are
two things to consider:
The amount of software available for granular synthesis
is small but it is growing. Most of the software available is shareware,
and available on the Internet. There is also specialist software that was
designed by composers for their own exclusive use. This is generally not
available. There are also sequencing programs such as Cakewalk for the
PC that allow the user to perform time stretching, but apart from this
one function are not designed for granular synthesis. Table 5 in the appendix
gives a summary of the most available shareware granular synthesis programs.
Csound,
written by Barry Vercoe, is for general synthesis use. It has been tried
and tested in various incarnations for at least 20 years now. It just requires
time and experimentation to get used to the interface. It has a semi-real-time
interface in that it does allow the sound to be played whilst it is being
compiled by the program. This is not true real-time synthesis though because
the creation process of a Csound texture is done on a text editor. The
text file must then be loaded into the compiler as a finished document
before it can make any sound. Being a text interface it offers much more
flexibility and control than any other program. There are not many functions
in the way of granular synthesis, but it is possible to make your own instruments
(Ekman 1998).
The
two granular synthesis commands it does have are grain and granule.
Grain is used for creating grains with similar contents. It has parameters
for amplitude, pitch, density, grain duration, and a number of random offsets.
It cannot be use for large samples though as it is not designed for time
stretching or such granular activities that require a sequential order
of grains.
Granule
on the other hand is designed with this purpose in mind. It has the same
options as grain, but it has extra control for sound samples. It allows
the user to specify how much of the sample to use, and where to begin the
sampling process, with associated random offset settings. It also allows
for multiple voices so you can layer different pitches on top of each other
that will play at the same rate (Ekman 1998).
The
main problem with these commands is that they receive all their data from
a function table, which must be defined previous to compiling the program,
which means that the user cannot create FM signals and send them straight
to the grain or granule command.
The song
Where
the Wind Meets the Sea (Track 2), uses the grain command exclusively
to create it's texture.