AS SPAWN Manuale utente
CONTENTS
INTRODUCTION
VCLFO
VCO
MIDI - CV MOD VCA
VCF
SOURCE MIXER
VCA
ENV
MIDI - CV
SPECIFICATION
BLANK PATCH CHARTS
ISOLATION PATCH
INTERNAL SIGNAL ROUTE
INTERNAL MODULATION ROUTE
1
2-3
4-6
7
8-9
10-11
12-13
14-15
16-19
20-21
22
23
24
24
INTRODUCTION TO SPAWN
SPAWN is a monophonic (one voice) Quasi modular rack synthesizer. It’s principle sound source the Voltage
Controlled Oscillator (VCO) generates a variable waveform along with two sub squarewaves and a white noise
source, these signals can be mixed and introduced into the resonant 24dB per Octave low pass ladder filter
(VCF). This stage is followed by a Voltage Controlled Amplifier (VCA). Both the VCF and VCA can be controlled
by the four part multi function Envelope Shaper. A Voltage Controlled low frequency Oscillator (VCLFO) is provided
for frequency and waveshape modulation.
SPAWN also includes a performance VCA (MIDI - CV MOD VCA) this will accept both audio and control signals
and can be controlled by both a control voltage or the internal high performance MIDI - CV convertor.
All signal and modulation routes can be isolated (see Isolation Patch pg 23) allowing for true modular synthesis.
SPAWN is provided with 37 3.5mm Jack sockets to allow signal and modulation patching.
1
2
V
VC
CL
LF
FO
OVOLTAGE CONTROLLED LOW FREQUENCY OSCILLATOR
The VCLFO is a wide range oscillator (usually operated in the non audio range)
used to modulate control inputs, e.g: used for vibrato, tremolo and trill. It is internally
routed to the VCO and VCF (see INTERNAL SIGNAL ROUTE page 3).
Four waveforms are simultaneously available and the Rate can be altered using
the linear CV socket.
LFO CONTROL
The Rate knob controls the speed of the modulation waveform.
The LED gives a visual indication of the speed of the VCLFO.
This output gives a positive sawtooth with an output voltage of +/-5 volts.
This output gives a negative sawtooth with an output voltage of +/-5 volts.
3
This output gives a squarewave output of +/-5 volts.
This output gives a trianglewave output of +/-5 volts.
This gives linear control of the VCLFO rate, e.g: from keyboard or envelope.
4
V
VC
CO
OVOLTAGE CONTROLLED OSCILLATOR
The VCO is the primary sound source within SPAWN.
It creates the raw waveform which is then processed and
modified by the other synthesizer circuits.
SPAWN contains a temperature compensated oscillator,
conforming to the industry standard logarithmic IV/OCT
response. For ease of control an internal patch from the
Midi/CV interface has been routed to a CV input of the
oscillator, it by passes the Glide control so that the Midi
keyboard controls the level of the Glide. This internal
route can be isolated using the Midi routing switch in the
Midi section.
FREQUENCY CONTROL
1A. In the ‘-2’ position the Tune knob controls the initial frequency of 16Hz by +/- one octave.
1B. In the ‘0’ position the Tune knob controls the initial frequency of 64Hz by +/- one octave.
1C. In the ‘W’ position (WIDE) the Tune knob has a range of approximately 12 octaves.
The Modulation knob introduces either triangle, square or no modulation to the oscillators frequency
(a maximum of two octaves, from the VCLFO).
5
The CV socket is the main IV/OCT control input for the VCO. This input will accept +/- control voltages and should
be your control input from a CV keyboard/controller such as the A.S French Connection, Sorceror or Demon when
used in the analogue mode. With the ‘Glide’ knob turned to the ‘F’ position (fast) no glide will be present. As the
knob is turned clockwise a slewing of the INPUT voltage will increase. This glide control is also known as
‘Portamento’ or ‘LAG’. If the Midi Convertor is being used internally this input can still be used, Midi generated
CV’s are not routed through the Glide control.
The Pitch Mod Socket and associated Amount Pot is another method of controlling the frequency of the Oscillator.
The Amount Pot also acts as an Invertor so that positive and negative frequency sweeps can be achieved from a
Positive Control Voltage. For instance the envelope sends out 0 to 9.5 volt, if the ENV OUT was patched to the
PITCH MOD INPUT in the full ‘+’ position the frequency of the VCO will increase by 9.5 Octaves. However with
the CONTROL knob in the full ‘-’ position the frequency of the VCO will decrease by 9.5 Octaves. Many control
VOLTAGE sources are available on a synthesizer both + and - AC or DC, so many types of frequency modulation
and sweeping is easily achieved. The closer the knob is to the ‘O’ position the smaller the amount of control.
This is a hard sync input used to reset the VCO waveform using a second oscillator. A wide range of
frequencies, waveshapes and levels will determine the type of sync generated.
WAVE SHAPING
The Wave knob controls the initial wave shape from the VCO. In the anti-clockwise position a sawtooth is
generated, in the clockwise position a pulse is generated, between the two positions the wave shape alters from
sawtooth through various sawtooth/squarewaves to a 5% pulse. The waveform is fully variable with no fixed point.
The Mod knob controls the amount of triangle modulation (from the VCLFO) or envelope modulation routed to the
waveshape. Pulse width modulation can be created using this method.
The Wave Mod socket and associated Amount pot is the way of externally controlling the waveshape generated
by the VCO. The Amount pot also acts as an invertor. So that the initial wave shape can be swept both positively
and negatively. For example the wave can be converted to a pulse wave using a positive control voltage and
having the amount knob turned clockwise (be aware of voltage level and amount knob position) like wise using a
positive control voltage but with the control knob turned in the negative position a pulse wave can be converted to
a sawtooth. This is a very important control and learning how to use it along with what to use it with will create
very unusual waveshapes.
This is the unmodified output of the VCO and has an output voltage of +10v ( in mode) as it concerts to the
5% pulse the output will have a +/- voltage of 10 volts when the sawtooth component of the wave shape has been
removed the square/pulse wave will be approx - 10v.
6
7
M
MI
ID
DI
I
-
-
C
CV
VM
MO
OD
D
V
VC
CA
A
The Midi-CV Mod VCA is a performance orientated VCA ,
there are two ways of controlling this VCA. The Midi control
input is routed to the Midi controlled Mod wheel output
(this may be isolated). Although primarily designed to allow
modulation control from midi this versatile VCA can also be
controlled by an analogue CV patched to the CV socket.
This socket is the control input to open the VCA when used in the CV analogue mode. It can be used even if the
internal Midi route is active.
This socket is the signal input to the Mod VCA. Audio and control voltages can be accepted by this input.
Example 1.
Awaveform from the VCLFO coming into the signal input can have its level controlled by an analogue voltage by
the CV this variable level control waveform available at the out socket could then be used to modulate a VCO or VCF.
Example 2.
An audio waveform could be sent to the signal input of the VCA as the CV is increased, the output waveform
level would increase patched to the ext sig in the VCF, a performance control could increase the level of the external
signal into SPAWN.
Two outputs are available from the Mod VCA simultaneous control of VCO pitch and VCF frequency is available.
*Note only Midi is pre-routed, all signal in’s, CV in’s and outputs must be made using the patch sockets.
8
V
VC
CF
FVOLTAGE CONTROLLED FILTER
The VCF in SPAWN is a low pass 24dB/oct transistor
ladder filter. It has the ability to attenuate/eliminate
frequencies above the cut off frequency point. This type
of filter is associated with the classic American ‘FAT’
analogue sound.
The Frequency knob (full name cut-off frequency) controls the point at which attenuation begins. Frequencies
above the cut-off frequency point are attenuated at 24dB/oct.
The Resonance knob is used to accentuate frequencies around the cut-off point, as the resonances increases the
filter will begin to ring and will self oscillate at high resonate settings producing a sinewave (the frequency of
which is controlled by the cut-off knob).
Indice
