ABOUT FM SYNTHESIS
Referring to our simple synthesiser in the diagram above we can outline the different sections & see that it comprises of two
blocks, each one containing one oscillator & one envelope. This is known as a 2 OPERATOR SYSTEM in DX7 Language
The DX7 had six operators & they were presented to the user in preset combinations referred to as ALGORITHMS. This terminolo-
gy of OPERATORS & ALGORITHMS immediately presented users of this new digital technology with a mystifying machine inter-
face, thus creating original sounds was very often left to professional programmers. We will to make things clearer with the
SUPERNOVA II so you may gain the knowledge to create your own FM sounds.
Programming of your own FM sounds using the Supernova II Rack.
In any one PROGRAM of the Supernova II Rack we can make up to 3 OPERATORS using the oscillators & envelopes available.
We can also add a noise waveform for special effects & Drum/Percussion sounds. For simplicity most of the factory presets use
the same structure as in the diagram below.
A Noise waveform maybe substituted for Osc1 or Osc2
Many musical instruments contain much of the detailed sonic information during the first few moments that the instrument is
plucked, struck or blown. For example when a Xylophone is struck, during the small amount of time after the beater has made con-
tact with the wood it will resonate & contain many harmonics. The sound will then settle down to a more periodic waveform.
The easiest way to learn & understand FM is to study a few of the factory presets. So lets start with the Xylophone
Select the FM sound Program D115"FMpt Xylo Lo".
When manipulating FM sounds most of the "tweaking" will be done in the using the envelope section & oscillator section.
Because we are now using an additive form of synthesis it is not really necessary to use the filter section. However it may be used
to enhance the sound further if required.
When using the Supernova II Rack for FM synthesis it is important to note that it is ALWAYS Oscillator 3 that is heard as an output
to the mixer section. If you are creating sounds from scratch we recommend using the program D126 “FM Init Program” as a start-
ing point as all the oscillators are set to sine waves & only oscillator 3 has its mix level turned up.
Operator 1
Operator 2
Osc1
Osc2
Env3
Env2
Osc3
Operator 3
Output
Env1
Amplifier
Operator 1
Operator 2
Output
16
Содержание Supernova II
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