Make Noise STO User manual

v2.5

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STO
Limited Warranty ----------------------------------------------------3
Installation --------------------------------------------------4
Overview --------------------------------------------------------5
Panel Controls -----------------------------------------------------6
The Waveform Outputs -------------------------------------7
FM, SYNC, and Variable Shape ---------------------------------8
Patch Ideas -------------------------------------------------------9

Limited WARRANTY:
Beta Analyst: Walker Farrell, Joe Moresi
Test Subjects: Rob Lowe, Joseph Raglani
About This Manual:
Written by Tony Rolando
Edited by Walker Farrell
Illustrated by W.Lee Coleman
Make Noise warrants this product to be free of defects in materials or construction for a period of one year
from the date of purchase (proof of purchase/invoice required).
Malfunction resulting from wrong power supply voltages, backwards or reversed eurorack bus board cable
connection, abuse of the product, removing knobs, changing face plates, or any other causes determined by
Make Noise to be the fault of the user are not covered by this warranty, and normal service rates will apply.
During the warranty period, any defective products will be repaired or replaced, at the option of Make Noise,
on a return-to-Make Noise basis with the customer paying the transit cost to Make Noise.
Make Noise implies and accepts no responsibility for harm to person or apparatus caused through operation
of this product.
Please contact [email protected] with any questions, Return To Manufacturer Authorization,
or any needs & comments.
http://www.makenoisemusic.com
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Electrocution hazard!
bus board connection cable.
Do not touch any electrical terminals when attaching any Eurorack bus board cable.
The Make Noise STO is an electronic music module requiring 40mA of +12VDC and 30 mA of -12VDC
regulated voltages and a properly formatted distribution receptacle to operate. It must be properly installed
into a Eurorack format modular synthesizer system case.
Go to http://www.makenoisemusic.com/ for examples of Eurorack Systems and Cases.
board connector cable on backside of module (see picture below), plug the bus board connector cable into
the Eurorack style bus board, minding the polarity so that the RED stripe on the cable is oriented to the
NEGATIVE 12 Volt line on both the module and the bus board. On the Make Noise 6U or 3U Busboard, the
negative 12 Volt line is indicated by the white stripe.
supply.
-12V
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Overview:
The STO is a compact Voltage Controlled Oscillator designed for generating Sine waves, Variable wave-Shapes, Sub-Octaves,
Oscillator SYNC and Linear FM in the analog domain. The Sub-Timbral Oscillator is the more subtle and melodic friend to the
DPO's complex harmonic lattice. The STO yields harmonically rich textures through the use of Hard Sync, Linear FM and Variable
Shape, but this VCO seems destined for melody.
The STO uses a Triangle Core and has outputs for Sine, SUB, and Variable Shape. The Sine is shaped from the Triangle using the
same circuit used on the DPO. The Sub-Oscillator has its own gate input that lets the user turn it on/o at will. The Variable
SHAPE ripples both Even and Odd Harmonics resulting subtle timbral shifts where the fundamental frequency is never masked.
When combined with the Sub-Oscillator output (at the input of the MMG, for example) this makes for a rich, strong melodic
voice.
The STO is a 100% analog musical instrument that is not suitable for laboratory use.
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STO Panel Controls
1. Variable Shape Waveform Output: 10Vpp
2. Sub-Oscillator Output: 12Vpp
3. Sine Waveform Output: 10Vpp
4. Coarse Tune panel control: 9 octave range 8hz-4khz
5. 1V/Octave Scale Trimmer (Calibration Use Only))
6. Fine Tune panel control: +/-2.5 semi-tone range
7. Linear FM Level: uni-polar attenuator for Linear FM input
8. Linear FM Input: AC coupled, 10V range
9. Variable Shape: Ripples Even and Odd harmonics. With nothing patched to Variable Shape CV Input, works as standard panel
control. With Signal Patched to Variable Shape CV Input, works as an attenuatr for that signal.
10. Variable Shape CV Input: Direct Coupled uni-polar control signal input, range 0V to +8V
11. Expo Input: Exponential frequency control input. Bi-polar, 10V range
12. 1V/Octave control Input: bi-polar pitch control, optimal range +/-5V
13. S-Gate: Resets and turns Sub-Oscillator ON at Gate High, turns O at Gate Low. Just about any signal that exceeds 1V
work here.
14 SYNC: Resets Oscillator Core. Just about any 10Vpp audio rate signal works here.
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The WAVEFORM OUTPUTS
There are three wave shapes that are derived from the oscillator core. These signals are all roughly 10V peak to peak and centered
around 0V (bi-polar). The Sine wave is derived from the Triangle core of the oscillator and is provided as an output because it is
great for blending with signals of greater harmonic content in order to strengthen the fundamental. The Sine shape has almost no
harmonics, so it is also a good starting point for creating complex FM sounds because the sidebands introduced through FM are
not be obscured by harmonics present in the signals utilized.
The Variable Shape is a unique waveform that is derived from the Sine. It is more harmonically rich then the Sine, but the
fundamental frequency is still very strong. The Variable Shape carries the harmonics and sidebands introduced through Hard
SYNC and FM with greater presence then the Sine shape. The end result is that the it will be more aggressive signal when using
Hard SYNC or FM. The Variable Shape is also excellent for patching Subtractive synthesis sounds.
The Sub-Oscillator is a stepped rectangular shape derived from the comparator on the core of the STO are aected by SYNC
patches as well as the EXPO, Linear FM, and 1V/Octave inputs and controls. The sound is similar to a Square wave, but it is one
octave below the frequency of the Variable Shape and Sine waveforms making it very pleasant to combine with these signals. It
thickens the sound and provides more harmonics for lters such as the MMG to work upon.
Control Inputs
There are several control inputs on the STO, all of which conform to the system wide standards. Just about any control or audio
signals are eective in some way at these inputs.
The EXPO CV Input is similar to the 1V/Octave Input and in fact could be used for adding a second sequence (combining two
sequences) or transposing a sequence patched to the 1V/Octave input. It is also highly useful for sweeping the Frequency of the
STO to animate SYNC sounds or percussion patches. If wild textures are desired, the Expo input could be used to implement
Exponential FM. When using for modulation be sure to patch a VCA such as the Optomix in series before the Expo CV Input as
there is no attenuator associate with this input.
The 1V/Octave Input is typically used for controlling the Pitch of the STO from a sequencer, CV Keyboard or Midi to CV converter.
It could also be used for all of the functions described above in the EXPO CV Input paragraph. When using for modulation, be sure
to patch a VCA such as the Optomix in series before the EXPO CV Input, as there is no attenuator associate with this input.
The S-Gate input turns ON, OFF, and Resets the Sub-Oscillator. Just about any signal will work as a gate at this input. There are
just two states, Sub On and Sub O. Additionally, the Sub resets at the onset of the Gate High state (Sub On). This input is useful
for animating the Sub-Oscillator, allowing it to have rythymic or percussive patterns not associate with the other outputs of the
STO. If more narrow signal is used at this input, such as Saw from VCO A on the DPO, it is possible to create sync type sound in the
Sub-Oscillator while the other outputs, Sine, and Variable Shape, are not aected.
The Linear FM input and associated attenuator is described below in the FM, Sync, and Variable Shape section. The SYNC input is
described below in the FM, SYNC, and Variable Shape section. The Variable Shape input and associated attenuator is described
below in the FM, SYNC, and Variable Shape section.
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FM, SYNC, and Variable SHAPE:
The STO is capable of generating harmonically rich waveforms. This is accomplished through the modulation of the Variable
SHAPE, FM and Oscillator SYNC.
Linear and EXPO FM
Frequency Modulation super imposes the frequency of one oscillator upon another. The result is that the oscillator that is FM'd will
carry the modulating oscillator's pitch information in the form of harmonics. Linear FM attempts to preserve the base frequency of
the carrier oscillator allowing for harmonically rich waveforms to be generated while still being able to track the 1V/ Octave scale
properly. The Linear FM input is AC coupled and has a Level control. As you increase the Level, the Amplitude of the signal
Frequency Modulating the STO is increased and the resulting signals at all outputs of the STO will become increasingly more
complex. At greater than 80% Level, the Linear FM bus goes into overdrive and the STO does not track accurately. Exponential FM
is also possible with the STO by patching your modulating oscillator to the EXPO input. You will want to patch a VCA such as the
OPTOMIX in series before the EXPO input on the STO to allow for Dynamic FM (voltage control over the FM Index). Exponenital FM
is much deeper and more complex then Linear FM; however, it severely changes the base frequency of the oscillator core and
therefore the STO no longer tracks the 1V/ Octave scale properly. Exponential FM is highly useful when you require complex
signals but you do not require proper tracking, for example, if you are programming percussion sounds.
Oscillator SYNC
SYNC patches introduce strong harmonics to all of the outputs on the STO. Sync uses a modulation method where the core of the
STO is made to conform to that of an external VCO. Once SYNC'd the STO core restarts its period at each cycle of the external VCO
signal, so they will have the same base frequency. Additional harmonics are achieved when the STO Frequency is Higher than that
of the external VCO to which it is SYNC'd. In a SYNC patch, the timbre of the STO may be altered by varying it’s frequency against
that of the Master Frequency as set by the external VCO signal. Slow sweeping modulation of the STO core Frequency, such as an
envelope or LFO patched to the EXPO Input, results in sweeping of harmonics. The best results are achieved by setting the
external VCO to a base frequency of at least at least 100hz (around A2) and sweeping the STO Frequency from 100hz up!
SYNC has the advantage of tracking much more reliably then Linear FM; however, the sound is much more aggressive.
Variable SHAPE
This circuit is unique to the STO. It gently ripples both Even and Odd harmonics, while always maintaining a strong fundamental.
At 0% the Variable Shape output is a Sine shape and at 100% it is a glitched triangle. Although it is well capable of audio rate
modulation, it is best served by slower modulations such as logarithmic envelopes and LFOs from MATHS and/or FUNCTION and
Smooth Random Voltages from the WOGGLEBUG. When modulated and combined with the Sub-Oscillator (at the inputs of the
MMG or Optomix) this output creates a very strong voice for melodic sequencing.

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Patch Ideas:
The Sub Timbral Voice:
Patch Variable Shape output to AC input of MMG. Patch Sub-Osc output to DC input of MMG. Set STO Freq to around 12:00. Set
MMG input attenuator to 1:00, MMG Freq full counter clockwise, MMG Q to 11:00 and Mode to LP. Patch slow LFO logarithmic
from MATHS to Shape CV Input on STO and set Shape attenuator to about 60%. Patch sequencer or keyboard CV to 1V/Octave
input on STO. Patch sequencer or keyboard gate to envelope generator such as MATHS or FUNCTION, programmed for fast Rise
Time, Slow Fall Time and Exponential shape. Patch this exponential envelope to the Freq 2 CV Input on MMG. Monitor MMG
Output.
Analog Bass Drum:
Patch Sine to Optomix CH. 1 Signal Input. Patch Gate to Linear FM Input and Optomix CH. 1 Strike Input. Set Linear FM amount to
12:00 and Frequency panel control to roughly 9:00. Set Optomix CH. 1 Damp and Control panel controls to full Counter
Clock-Wise. Monitor Optomix CH. 1 Signal Output. Adjusting the Linear FM amount, Frequency setting, and Damp settings allow
you to create many dierent Bass Drum sounds. Adding Expo FM from another VCO expands the possibilities.

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Patch Ideas:
Transposition/Superimposition
Patch a sequence such as from Rene to the STO’s 1V/Oct input. Patch another sequence of a dierent speed, or control voltage
from a keyboard, to the Expo input. The two sequences will be “added” together for transposition. Variations would include:
clocking the transposing sequence at an odd division of the master clock, resulting in long periods between exact repetitions;
deriving the transposing sequence from the master sequence via sample and hold; tuning a square wave LFO to +/- 1V for double
octave leaps.
Dual Sync
Patch an audio-rate square or sawtooth wave to the STO’s S-Gate input, and another to the Sync input. The Sub output will be
“pseudo-synced” to a dierent frequency from the Sine and Variable outs. If the Sync sources are related, such as from two sides of
a DPO with Following engaged, so will be the STO’s outputs.

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Patch Ideas:
Key Tracking
Mult the control voltage in the 1V/Oct input to the Shape CV input and take output from Variable Wave Output. This results in
higher pitches having more harmonic content, similar to keyboard tracking on a low-pass lter.
Bassline
Patch a low-frequency square wave (or EOR/EOC gate from cycling MATHS, FUNCTION, or CONTOUR) to the S-Gate input, and take
output from SUB Out. Mult the square wave to the Clock input of a sequencer and patch the sequencer’s output to the STO
1V/Oct input. Adjust square wave pulse width (or MATHS/FUNCTION/CONTOUR’s Rise/Fall times) to change the length of“notes.”