E-Mu EMAX, Owner'S Manual

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Emax Owners Manual
© 1986 E-mu Systems, Inc. Enhanced by The Emulator Archive 2001 Page 13
INTRODUCTION
EMAX BASICS
DEFINITIONS, BACKGROUND, and BASICS: HOW EMAX ORGANIZES SOUND
READ THIS SECTION CAREFULLY OR THE REST OF THE MANUAL WILL NOT MAKE SENSE!!
Throughout this manual we will use the terms and concepts described and defined below. Read through
this section carefully, even if you don’t retain it alt, and refer to this section periodically as you read the
manual until you know the meaning of all the following definitions.
SAMPLING BASICS
Emax is conceptually like a tape recorder in that it records sound. However, the recording process is very
different since Emax records into its computer memory.
Computers can accept information only in the form of numbers, so first Emax converts audio signals into
numbers. It does this by examining (sampling) the incoming signal level at a nominal rate of 28,000
(actual rate is 27,777.8) times a second, and sequentially records these different levels in computer
memory. Fig
. INTRO-1 shows a one-second percussive sound being sampled. The magnified view shows
how the samples define the instantaneous level of the signal. Once stored in Emax’s memory bank, these
samples may be played back (in the proper sequence, of course) to reconstruct the original signal. If a
two-second sound was being sampled, it would require 2 X 28,000 or 56,000 samples at the nominal
sampling rate. Shorter sounds require fewer samples. Note: The sampling rate can be altered for
reasons, which we will get into later.
Just like tape, a sound can be manipulated once it has been recorded. Playing back the samples in the
reverse order from which they were stored plays the sound backwards. Playing back the samples at a
faster rate than the rate at which they were stored raises pitch; playing back at a slower rate lowers pitch
(like a tape recorders variable speed control).
THE EMAX “MAP”
Sure, you’re anxious to start coaxing wonderful sounds from the instrument - - but like ground school for
pilots, the following is a necessary part of learning how to play Emax. It is important to understand how
Emax organizes sounds In order to make best use of the instrument in the shortest possible time. Also,
many terms will be introduced now that show up later in the manual.
You can think of Emax as resembling a collection of modules, linked by various pathways (see the Map in
Fig. INTRO-2). These paths indicate how information flows within Emax; let’s take a closer look at what
makes up this information, and how it is transferred from one section of the instrument to another.
THE BANK
The Bank contains all of Emax’s memory, which includes Preset, Voice, Sample and Sequence data.
Consider the Bank as the central storehouse for all of Emax’s data. Although the memory is volatile,
meaning that the data disappears when you turn off power, the Bank data can be saved permanently on
disk to keep a record of your work. (This process is somewhat like saving the data in a regular polyphonic
synthesizer to cassette, but using disks results in far more efficient operation.)