Novation PEAK - PEAK IN DETAIL & ADVANCED FEATURES; Oscillator, LFO, Filter Sections

17
PEAK: SIMPLIFIED BLOCK DIAGRAM
Voice 1
Voice 2
Voice 3
Voice 4
Voice 5
Voice 6
Voice 7
Voice 8
Global FX
- Delay
- Reverb
- Chorus
Mixer
Osc1
Osc2
Osc3
Overdrive
Analogue
Analogue
FPGA
AnalogueAnalogue
Left Output
Right Output
Effects Send
Effects Refturn
VCA left
(Sum)
Post VCA
Distortion
VCA left
VCA right
Mixer
Overdrive Filter
Pre VCA
Distortion
VCA left
VCA right
Mixer
Overdrive Filter
Pre VCA
Distortion
VCA left
VCA right
Mixer
Overdrive Filter
Pre VCA
Distortion
VCA left
VCA right
Mixer
Overdrive Filter
Pre VCA
Distortion
VCA left
VCA right
Mixer
Overdrive Filter
Pre VCA
Distortion
VCA left
VCA right
Mixer
Overdrive Filter
Pre VCA
Distortion
VCA left
VCA right
Mixer
Overdrive Filter
Pre VCA
Distortion
VCA left
VCA right
VCA right
(Sum)
Post VCA
Distortion
Pre VCA
Distortion
Filter
Peak has eight separate voices, which are treated independently throughout the remaining
signal chain. The voices are synthesised digitally in a Field Programmable Gate Array
(FPGA) using Numerically Controlled Oscillators running at an extremely high clock rate,
resulting in waveforms which are indistinguishable from those using traditional analogue
synthesis.
Each voice is a mix of the outputs of the three oscillators; when you adjust one of the
oscillator level controls
19
,
20
or
21
you are effectively adjusting the level of eight voices
simultaneously. The subsequent elements in the signal processing chain are entirely in the
analogue domain. Note that distortion can be added in several places – before the filter
(Overdrive
37
), after the filter (Filter Post Drive in the Voices Menu) and after
final voice summation (Distortion Level
43
). The sonic effect can be quite different in
each case.
Note that the time-domain effects (FX) – chorus, delay and reverb – are digitally generated
within the FPGA as well. The stereo effects send into the FX processing section is taken
from post the main VCA, so all distortions added to the signals are processed by the FX.
The FX return signal is added back to same point in the signal path.
PEAK IN DETAIL
In this section of the manual, each section of the synthesiser is discussed in greater detail.
The sections are arranged in order of “signal flow” – see the Block Diagram above. Within
each section, the surface physical controls are described first, followed by a reference
guide to the display menu relating to the section. In general, the menus offer “fine control”
parameters to which access is less readily required. The “initial value” given for each
parameter is that for the factory Init Patch: these will differ when another Patch is loaded.
We must emphasise that there is no substitute for experimentation. Adjusting controls
and tweaking individual parameters while listening to different Patches will tell you more
about what each parameter does than this User Guide ever could. In particular, we would
encourage you to experiment with the effect that varying a parameter has on different
Patches – you will find there can be considerable differences between Patches, depending
on how the sound is being generated.
The Oscillator Section
7 8 9 10 11 12 14 13
Peak’s Oscillator section consists of three identical oscillators, each with its own set of
controls. The following descriptions thus apply equally to any of the oscillators.
Wave
The Wave button
10
selects one of five wave shape options: four are the common
fundamental waves, Sine, Triangle, (rising) Sawtooth and Square/Pulse.
The fifth option, more, allows selection from a range of 60 further wavetables, accessed
via the WaveMore parameter in the Oscillator menu (see page 18). The LEDs confirm
the waveform currently selected.