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Nord Wave User Manual v1.1
Introduction
Subtractive synthesis is one of the oldest and most widely
spread forms of synthesizing sounds. It is the method em-
ployed in classics as the Moog synthesizers, the Sequential
Prophet-5 and 10, arp synthesizers, most oberheim syn-
thesizers, the roland Jupiter models, the tB-303 etc; the list
is practically endless. Even new digital instruments such as
workstations and sample playback devices employ many of
the basic principles of subtractive synthesis.
With the first Nord Lead, Clavia introduced a new concept:
a modern digital instrument that combined a faithful re-
production of the behavior of the old analog favorites with
the convenience and stability of the newer designs. the
Nord Wave takes this concept even further, adding valu-
able new features and functionality such as FM, Wavetable
and sample playback.
the purpose of this chapter is to give you a quick introduc-
tion to this world of subtractive synthesis as used in the
Nord Wave and its analog predecessors. If you’d like to
know even more, there are number of text books or web
based info that will expand on this subject.
The “building blocks”
Subtractive synthesis started its life in modular synthesiz-
ers, large cabinets housing separate electronic modules,
connected via patch cords. With the advancement of
technology, the functionality of many of these modules
could be put onto one single circuit board. But function-
ality-wise, subtractive synthesizers are still built out of the
same modules (or building blocks) as they were decades
ago. Subtractive by the way, comes from the way a filter
traditionally behaves; by subtracting harmonics from a
waveform.
We will now take a closer look at these building blocks.
Let’s first talk about the three that actually create and
process sound:
Oscillator
the oscillator is actually the only thing in a synthesizer that
actually produces any sound, (all the other modules only
shape the sound from the oscillator.) the oscillator is a bit
like the string on a string instrument, it vibrates to create
sound.
Filter
the signal from the oscillator is sent through the Filter
which shapes the timbre of the sound to make it “bright”,
“dull”, “thin”, etc.
Amplifier
the amplifier shapes the volume of the sound making it
“soft” or “hard”, “slow”, “plucked” or “short”.
Modulation
In addition to these main modules all synthesizers also
have “modulators”, devices that can make the volume, tim-
bre pitch and other qualities of sound vary continuously
over time when you play a key.
It is these modulators that basically add animation to the
sound, taking it from a dull organ drone to a dynamic and
interesting timbre. the two most common modulators are
Envelopes and LFos.
Envelopes
an envelope is used to give a sound a “shape”. If you apply
an envelope to the amplifier (which controls the volume)
you are able to make the sound for example slowly fade in
and then fade out when you press and hold a key.
LFOs
LFo is an abbreviation for Low Frequency oscillator. It is
used for repeating variations in a sound, such as vibrato or
tremolo.
Connections
there are many ways in which the modules outlined below
can be connected in a synthesizer, but the one in the
picture below is a basic and common one, used in the Nord
Wave (although the illustration depicts far from all the pos-
sibilities in this instrument!)
Note that the horizontal lines indicate the way the sound
travels. the vertical lines indicate control signals.
the envelopes for example only modulate (control) the
oscillator, filter and amplifiers, they do not affect the sound
directly.
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Synthesis Basics