Edison ED!SON WaMi Box, Руководство пользователя

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Ed!son –Instrument Editor 13
In Ed!son, the individual samples (and their keyboard zones) are referred to as
splits. A further use of splits is the realization of drum kits, i.e. a collection of
various drums and other percussion instruments. Strictly speaking, a drum kit is
nothing more than a multi-sample, several samples distributed across the keyboard
within an instrument sound.
Sample loops
All samplers, including the WAMI BOX, have a number of design limitations: The
number and size of the samples which can be stored on the WAMI BOX is more
or less limited the amount of sample RAM with which the sound card has been
equipped. Of course, memory chips are no longer one of the earth's most precious
resources, but careful budgeting is a good idea nevertheless - even though the
EWS can be equipped with up to 64 MB of sample RAM.
Sampler manufacturers have come up with a special trick which contributes
significantly to conserving sample RAM: the sample loop. If you have a closer
look at the samples of many instrument sounds, you will find that there's a lot of
activity at the beginning, which then goes over to a relatively constant progression.
A piano sound is a good example. Striking a piano key causes the sound to
develop very quickly. It then goes over to a constant tone (the vibration of the
string) which gradually decreases in volume and fades out.
We apply precisely this characteristic to shorten our samples and conserve
sample RAM. The fact that the sound decreases in volume is no problem, as we
can take care of that later with the volume envelope. The crucial point is that the
sound takes on a continuous quality after a given period of time. If only a small
section of this continuous-tone period is repeated for the entire period during
which the key is held, it is then possible to cut off the entire rat's tail of audio
information following it.
In practice, the sample loop part of the wave file, i.e. the part to be repeated
infinitely, can be defined in practice with Ed!son Wave or other suitable sample
editors.