Artisan Electronic Instruments Ottava User manual

Ottava User’s Manual
Analog Hybrid Performance Synthesizer
Artisan Electronic Instruments© 2016
All Rights Reserved
www. ArtisanElectronicInstruments.com

Contents
Your Ottava Performance Analog-Hybrid Synthesizer ................................................................... 3
Right Up Front................................................................................................................................. 4
Ottava’s Voice ................................................................................................................................. 6
Sources............................................................................................................................................ 7
Oscillators.................................................................................................................................... 8
AXoR Function........................................................................................................................... 10
Noise Source ............................................................................................................................. 12
Filter .............................................................................................................................................. 13
VCA................................................................................................................................................ 14
Envelope Generators .................................................................................................................... 14
LFOs............................................................................................................................................... 16
Trigger ........................................................................................................................................... 17
Modulation Selection and Modifiers ............................................................................................ 18
Multiplier................................................................................................................................... 20
Adder......................................................................................................................................... 21
Contour ..................................................................................................................................... 21
MIN-MAX .................................................................................................................................. 22
Quantizer................................................................................................................................... 22
Lag ............................................................................................................................................. 22
Patch Save, Recall and Assign ....................................................................................................... 23
Play Patch.................................................................................................................................. 23
Save Patch................................................................................................................................. 23
Assign Button 1-10 and Quick Patch......................................................................................... 24
MIDI and Mode Setup................................................................................................................... 25
Specifications ................................................................................................................................ 25
Parameter access and MIDI CC Assignments............................................................................ 26

Your Ottava Performance Analog-Hybrid Synthesizer
So you just un-boxed your Ottava.. nice feeling isn’t it? If you are like me, you just want to get
playing... Well that’s easy, let’s do it!
Plug in the adapter
Turn on the switch
Hit the Trig button (it’s the upper button on the far right side of the front panel)
Woah!
So what just happened? Ottava, when powered up, automatically loads the patch assigned to
quick-patch button #1. The Trigger button acts like 1/12th octave keyboard and plays a note
just as if a MIDI keyboard was attached. (You can change this note and this initial patch it you
want… we’ll get into that later.)
If you love this sound as much as we do, just plug in a MIDI keyboard or sequencer into the
MIDI In port and go play… Come back here when you’re done and we’ll fill in the rest. See you
later!
Welcome back! So you twiddled some knobs and pressed some buttons and we hope most of
that was intuitive and fun. This manual will hopefully help with the rest.
We’ll go over the Front Panel and let you know what all those buttons and knobs do
Next we’ll introduce the sound path and modulation routing
Then we go into detail on each section of the synthesizer
The next section will go into detail on how to assign modulation and make new
modulations using the Modifiers
Then we will go through the other menus and describe how to save and play patches,
update software, apply tuning, get to “secret” parameters and setup the MIDI
functionality.
Finally, we have the obligatory specification page. He, we’re proud of this thing and we
love to show off its dimensions and power.

Right Up Front
Ottava has 25 knobs and 15 push buttons for direct control of most functions. Very little menu
diving is required to setup a patch… wouldn’t be a performance synthesizer if it did, right? But
we did need to keep this thing compact while providing so much under the hood…
…So several knobs are used to control different banks. These banks are selected by the Source
and Modulation Select buttons and indicated by the corresponding LEDs.
Let’s just take a look; this is the Atomic version, but the Baroque follows the exact same
layout…
The panel is set out in 4 sections; Data, Source, Tone and Modulation.
The Data section is where you can set Ottava’s operational mode and MIDI channel, update
firmware, store and assign patches, dabble in alternate keyboard tunings and configure the
modifiers.
The Source section is where the sound starts. This is where you get to mix the analog
waveshapes, add the sub oscillators, engage the hard sync and choose the AXoR functions.
Pitch and shape modulation sources and amounts are directly accessible. The Noise Source can
Source Selector
Modulation Selector
Data Section
Source Section
Tone Section
Modulation Section
External Pedal/CV IN
MIDI I/O & Audio Out

be brought in and has both pitch and level modulation. All this is mixed and sent to the next
stage…the filter.
The Tone Section contains the controls for the 4 pole cascade low pass filter. This 24db filter
starts with an over-drivable asymmetric soft clip distortion stage and mixes in the feedback to
create smooth to sharp singing resonance. In addition to the adjustable key-tracking, there are
2 selectable cut-off modulation sources and amount controls for a wide range of harmonic play.
The tone section ends in a classic VCA also with 2 modulation sources and amount controls.
The final section provides direct control of 4 six-stage envelope generators and 4 eight-
waveshape LFOs. Envelope generators can be triggered in 3 modes or set to a looping mode
(what could you do with 8 LFOs!!) LFOs can run free, be synced to the keyboard or set to run
once, providing 4 more AR-like functions (what could you do with 8 envelope generators!!)
Additionally, the LFOs have rate modulation allowing very naturally flowing vibratos to wild
time-shifting modulation waveshapes.
The Trigger button allows Ottava to play on its own. A simple way sample the sound or to use
Ottava as a drone box.
TIP: To read the present value of a sound parameter without changing the value, press and
hold the Green button and then slightly rotate a knob that you are interested in and the
present value will be displayed on the OELD, unchanged.
By the way, the power switch is on the top panel, just to the right of the Audio Out ¼” jack… Of
course you know that, but just thought we should say that somewhere in this manual.

Ottava’s Voice
All those knobs and buttons and LEDs on the Front Panel exist for one basic purpose, accessing
the sound engine under the cover. Without this, Ottava would just be a cool looking MIDI
controller. Thank goodness there is that second PCB.
Behold!
On the left, you can follow the analog signal path from dual VCO, subs, Noise and AXoR,
through the mixer to the VCF and VCA. The red signals connect to knobs on the Front
Panel; the green signals are connections to the modulation matrix.
The Modulation matrix takes the output signals form the four LFOs, four envelope generators,
various Modifiers (adders, multipliers, etc) and the keyboard and routes them to the various
destinations. All 21 modulation outputs are available to all 25 destination inputs
simultaneously. Why have modulation matrix limits?
Any every setting and routing can be recorded in a patch. Nice.

Sources
The harmonic character of a sound starts with the oscillators, so Ottava was designed to
provide a wide range of control and capabilities in its stable oscillators without sacrificing the
warmth and feel that can only be derived from a discrete analog design.
There are two “nearly” identical analog oscillators in Ottava. The waveform generation starts
from a classic Ramp-core, from which Triangle and Pulse waveforms are derived. The sub-
oscillator is also driven from this core. After generation, all 4 waveforms are sent through the
digitally controlled analog mixer.
The Shape Modulation morphs a Ramp, into Blade and Triangle waveshapes and the Pulse
Width Modulation produces Square to Spike waves. The sub-oscillators have a few tricks
themselves and can have selections for 1 or 2 octaves down and produce both square and
smooth waveforms.
As you can imagine, all this provides wide sonic capability and control. And then there is Hard
Sync and the AXoR to really up the harmonic spectrum!
Hard Sync forces Oscillator 2 to reset its ramp core under the tyrannical control of Oscillator 1.
It’s hard to describe the unique sound this produces and small variations of pitch offset can
create wide ranges of tone.
Waveshape
Modulation
Amount
Select Pitch Modulator
Hard Sync Button
Hard Sync Indicator
Section
Sub Oscillator Shape,
Octave and Level
Pitch Semitones
Selector
Pitch Modulation Amount
Section
Pitch Cents
Section
Glide Rate
Section
Waveshape: Saw to
Triangle and PWM
Select
Waveshape
Modulator
Button
Osc 1, 2 AXoR, Noise indicator
Wave Level
Levelection

Last but definitely not least is the AXoR oscillator combining, wave mangling advanced logic ring
modulator. This takes both oscillators and both sub-oscillators and generates 17 different wave
functions producing mild bell-tones to wild thrash.
Wait, how could we forget the Noise Source? This is no ordinary noise generator. It has both
independent Color and Amplitude modulation capabilities. This guy can create everything from
a pulsing breathy flute character to deep rumbling explosions.
So in the end, there are 10 sound sources running into the mixer and feeding that filter. 10!
Oscillators
The Oscillators are true VCOs, voltage controlled saw-core frequency discrete component & op-
amp goodness. The Saw wave is transformed by Triangle wave converter and Pulse Width
Modulation circuits. Additionally, the core signal is passed to the sub-octave circuit that divides
the signal into 1 and 2 octaves down square waves, which are passes through 2-pole Bessel
filters to provide additional smoothed waves for the subs… It’s all these sub-octave options
found on both both oscillators that give rise and credence to the OTTAVA name.*
The Waveshape knob morphs the core waveshape from Saw through blade through Triangle
waves continuously. Shape modulation directly effects this morphing and can add subtle
texture to the sound.
Beyond the half-way 12 o’clock point, the Waveshape knob waveform changes to Square wave
and the position of the waveshape knob controls Pulse Width. Shape modulation now provides
that classic and wonderful PWM* sound.

* PWM modulation can change the shape from 0% to 100% pulse width. 0% and 100% are
actually useful... it is a neat trick to remove an oscillator from the mix dynamically
The Wave level knob controls the mix level of the fundamental waveshape.
The Sub-Oscillator shape control knob combines functions; Sub-Level, Sub Octave and Sub
Shape. Thus the knob has 4 sections;
One octave down, smooth shape
One octave down, Squarewave shape
Two octaves down, smooth shape
Two octaves down, Squarewave shape
Within each section, the mix level of the selected sub-wave increases from 0 to 100%.
There is one difference between Oscillator 1 and 2 (remember all modulations, levels, bend
amounts, glide etc are completely independent for the 2 oscillators!) and that is Hard Sync.
Hard Sync takes a sharp pulse from the edge of Oscillator 1 and resets the Saw-core generator
of Oscillator 2. Normally, you would then take Osc1 out of the mix and listen to Osc 2 as that is

where all the fun is happening. To turn on Hard Sync, just press the button and the LED will
light up, telling you its on.
This is what Hard Sync looks like.
Osc 1
Osc 2
Result
You can see that the result has one more peak and that the Osc 2 waveform (what the
waveform would have been if not for the Hard Sync) was “cut short” in two places because of
the reset by Osc 1. The result contains new harmonics and a new fundamental pitch… can be
quite dynamic. Small changes to Osc 1 or 2 frequencies can create large harmonic changes.
There are 2 knobs to control fundamental pitch. The Big Kknob is chromatic and steps by
semitones (notes) and the fine pitch allows precede +/- one semitone (+/- 100 cents).
And don’t forget the Glide knob... each osc has its own glide rate…and Pitch Bend amount.
That’s the only one you need to get to through the parameter menu.
AXoR Function
The AXoR function is unique (as far as I know) to Ottava. The AXor is a digiat ring modulator on
steroids… and it shows. Most ring modulators take in 2 sources, the AXoR takes in 4. The PWM
from each Oscillator and the two Sub-oscillators. It then allows 3 types of Waveform
Transforms, 2 of which have 8 sub-functions.
The three transforms are
Bells (Combines the 2 oscillator’s PWM waveforms)
Clanks (Combines the 2 Sub-oscillator’s waveforms)
Thrash! (Combines all 4 waveforms!)

The Clanks and Thrash transforms have additional sub functions
1-4 Select combinations squares waves from the sub-oscillators
5-8 Select frequency dependent combinations.
For the Bells and Thrash transforms, the pulse width setting of each oscillator affects the
resulting tone tremendously.
Here is how the Front Panel Source Controls function when in the AXoR selection mode;
Having the Osc 1 pitch available is a helpful as this I one of the most important sonic character
influences. Remember to turn the oscillator and sub oscillator mix levels off if you want to hear
just the AXoR function. BTW, try Hard Sync with the AXoR sometime too.
Sub-functions 1-8
Osc 1 Pitch Semitones
Osc 1 Pitch Cents
Section
Transform:
Bells, Clanks, Trash!
AXoR LED
AXoR Wave Level
Levelection

Noise Source
The noise source on the Ottava is digitally generated. It can provide a very random white noise
source (has over 10 years before the pattern repeats, this is not a 1980s noise source, no chug-
chug sounds here). Being digital has its benefits. For one, it allows the noise to change “color”
and change the sonic “pitch” of the noise.. not quite like have pink to red noise, but different
and useful in its own way. Remember those arcade game explosion effects? No problem for
Ottava.
That’s because Ottava allows both the Color/Pitch and the Level to be modulated. Basically, the
Noise Source has its own VCA into the final mixer pre-filter. Add an Envelope generator to the
Level and Pitch modulation and Booom; Explosions, space drums or percussive attacks to organ
or flute sounds.
Here is how the Front Panel Source Controls function when in the Noise Source mode;
* Ottava means and octave higher or lower as written in music notation.
Level Modulation
Amount
Select Pitch Modulator
Color/Pitch
Pitch Modulation Amount
Section
Select Level
Modulator
Noise Source
Initial Noise Level
Levelection

Filter
So with all that sonic character control coming from the Sources, who needs a filter? Well you
do and Ottava provides a beautiful 4 pole cascade resonant filter. The 24db/octave filter can go
from smooth through some wild high resonance sizzle to full-self oscillation sinewave that
tracks perfectly over a 5+ octave range.
The filter cutoff can be modulated by 2 different sources of your choice from 21 different
modulation sources. Keyboard tracking can be set from 2x inverted tracking to 2X positive.
We know you will love sweeping this filter, so Ottava has a nice big knob right in the middle of
its panel. You can thank us later… 
Here is a basic look at the Filter Signal flow;
Select Cut-off
Modulator 1 & 2
VCA Modulator Amount
VCA Final Volume
Cut-off Modulation
Amount
Cut-off
Frequency
Section
Resonance Amount
Filter Key/Pitch
tracking
Select VCA
Modulator 1 & 2
Clip
+1

The Clipper is a soft asymmetrical distortion circuit that can be overdriven by the mixer stage.
Simply crank up the Source levels. The 4 signel1 pole filters are identical OTA based circuits and
the feedback path provides the Q peak or AKA Resonance. There are some additional circuits to
reduce the effect that higher resonance has on bass and signal level… but you get the basic
idea.
The two Cutoff Modulation sources combine with the Cutoff knob to create a voltage that is
converted to a current that then equally affects the corner frequency of each pole. Classic
analog VCF design. Yes, there are transistor ladder filters and State Variable Filters, but a
Cascade 4 pole is a classic too.
VCA
Yep, there is a OTA based analog VCA at the end of the signal chain. It also has two modulation
inputs. Typically these are set to an Envelope and a LFO… but replace one of these with the
Offset modulation source and you have a Drone box.
Envelope Generators
There are 4 identical Envelope Generator in Ottava.. We resist using the ADSR term because
they are more than that. We could use DAHDSR as that is a more accurate abbreviation (and
you will find this term used sometimes) . So what is a DAHDSR?
Envelope
Trigger
The Attack, Decay, Sustain and Release phases are controlled by their respective knobs. For
ADR phases, these knobs are exponential, with the fastest response fully CCW (about 4ms) and
slowest response CW (about 10sec). Sustain is Linear.
Delay and Hold share the same knob. Center is zero for both, CCW increases the Delay an CW
increases the Hold. To get both functions at once, set the delay or hold on the knob and set the
other using the Parameter Menu function.
Delay
Attack
Hold
Decay
Sustain
Release

The Envelope generators have 4 triggering modes;
Gated = Envelope will go through the DAHD stages and stay at the Susteian stage as
long as any keys is down. It will not re-trigger n a new note.
Soft = The Envelope will re-trigger on each note back to the Attack phase, starting at the
present level.
Hard = The Envelope will re-trigger on each note back to zero and restart at the Delay
stage.
Looping = The Envelope will run through the Delay, Attack, Hold, Decay and Release
stages and will restart again over an over as long as there is a key down.
Soft
Trigger
Hard
Trigger
Looping
Trigger

LFOs
Ottava also has 4 LFOs.. for the most part they are identical except LFO 1 runs 4 times faster
than the other 3… It runs up to 80 Hz.
The LFOs produce one of 8 waveforms;
Ramp Up
Ramp Down
Square
Triangle
Bipolar Triangle
Bipolar Sine
Random
Random Slope
The Bipolar waves modulate both + and –equally and are thus great for vibrato as they will
keep the fundamental pitch intact, no matter how much vibrato is dialed in. All the other wave
shape go from 0 to +100% modulation only. (you can always get negative modulation by turning
any Mod Amount knob CWW past the center detent)
The LFOs will run in one of 4 modes:
Free. = waveform is just running at the LFO rate set
Sync = Waveform always starts at 0 at the first key press and then runs free
Once = Waveform starts at the keypress and runs one and only one complete cycle.. like
a mini envelope generator.
Repeat = Line Once, but the waveform will repeat with each keypress.
LFOs have something that the Envelopes do not, and that is rate Modulation. And yes, you can
even modulate the LFO rate based on its own output… it turns that linear Ramp up into an
exponential Ramp.

Trigger
The Trigger button will trigger the envelopes and LFO sync. The Note played by the Trigger
button (Trigger Note #) can be adjusted under the Parameter menu.
To access the Trigger Note # parameter, rotate the Data Knob until it says “Parameters” and
then press the Data Knob. Rotate the Data Knob 7 clicks CCW to “Trigger Note #”. The Y/Right
knob will now select the MIDI Note that will be played when the trigger is pressed. You can
play Ottava and edit the sound while in the Parameter Mode, so go ahead and press the trigger,
adjust the pitch, play again… who knows, you could get good at this! Try playing “Mary had a
Little Lamb”.., come on, you know you want to!

Modulation Selection and Modifiers
The key to giving “life” to a sound is the subtle and sometime wild application of modulation.
In Ottava, all 21 modulation sources are available to any of the 25 destinations, but those
destinations need to be set and selected.
Modulation destinations into the voice are selected by pressing one of the 7 Source Select
buttons. (in light blue below)
Once the desired button is pressed (you don’t need to hold it down), the first line of the OLED
design will show which Destination is being address; such “Osc 1 Pitch Src” or “Osc 2 Shape
Src”… which reminds me, make sure you have selected the source or modulation desired first,
using the Selector button at the top of the Front panel.
The second line of the OLED display will show the presently, in-use, modulation for that
destination. To change the modulation used, rotate the Y/Right data knob… a list of
modulations sources will scroll through. You can ply the synth and hear the results of the
modulation on-the-fly. Just stop on the one you like… Note that you have a few seconds after
pressing the Modulation Section button to start selecting a new modulation.
Each Modulation destination has an Amount knob on the Front Panel that allows for +/- 1--%
modulation depth… they also have a nice detent in the center for easy 0% selection. For the
Filter and VCA, which have two sources of modulation, press the Modulation Selection button
first and then adjust the Amount knob. This tells the control card which modulation source you
want to control. The OLED always lets you know what is going on…
Modulation Section Buttons
Modulation Section Knob

Here is the Modulation list controlled by the Y data knob:
No Modulation
Velocity
Mod Wheel
Pitch Bend
After Touch
Ext Pedal CV
LFO 1
LFO 2
LFO 3
LFO 4
Envelope 1
Envelope 2
Envelope 3
Envelope 4
Multiplier 1
Multiplier 2
Adder
Contour
MIN-MAX
Quantizer
Lag
Offset (apply a constant modulation… actually useful)
Pitch (The MIDI note #)
The RED modulations are Modifiers. Modifiers take a modulation source and apply some
mathematical function to create new unique modulations.

Modifiers have their modulation sources selected differently. This is one of those time we have
to dive into the menu.. Rotate the Data Knob until it says “Modifiers” and press the data knob.
At this point, the OLED will switch and display something like;
The Data Knob will select which Modifier is being updated. The X/Left knob will select the First
Modulation Source and the Y/Right knob will select the setting or second modulation source.
The Multipliers, Adder and Min-Max require 2 sources while the others take a single
modulation and modify it.
Multiplier
The Multiplier takes two modulation signals and…. multiplies them. Big Surprise. But it does a
few other things too. It never lets the total value go above 100% modulation and it is a 4-
quadrent multiplier, so it takes into account the sign of the modulation, as from the LFO bipolar
signals. It also allows you to invert the second modulation signals That what the ”-“ you see is
when you go past center in the Y/Right data knob.
BTW, you have 2 of these…
M o d i f i e r M u l t 1
L F O 1 A F T R T C H
Rotate for Modifier Selection
Press to apply settings
Modifier Setting or
Second Modulation
Source
First Modulation Source
Can always press the Escape
button to get out unchanged
Modifier being adjusted