Qu-Bit Electronix Chord v2 User manual

Chord
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Contents
Description 4
Specifications 5
Installation 6
Marked Diagram 7
Functional Overview 8
1. Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1a. Coarse Tune . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1b. Fine Tune . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.Bank.................................... 8
Factory Banks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3. Waveform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4. Linear FM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5. Voicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
6. Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.Mode.................................... 10
Melody Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Free Poly Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Unison Poly Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
8.Harm.................................... 11
Normal and Melody Mode . . . . . . . . . . . . . . . . . . . . . . . . 11
Poly Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
9.Triad .................................... 11
10. V/Oct . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
11. Lead . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
12. Root . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
13. Third . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
14. Fifth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
15. Seventh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
16.Mix .................................... 12
Edit Functions 13
Accessing User Chords . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Creating User Chords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
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Creating User Chords on the SD Card . . . . . . . . . . . . . . . . . . 13
Creating User Chords on the Chord . . . . . . . . . . . . . . . . . . . . 14
Accessing User Wavetables . . . . . . . . . . . . . . . . . . . . . . . . . . 14
SD Card Information 15
chord_config.txt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
QUANTIZE_AUTOHARM . . . . . . . . . . . . . . . . . . . . . . . . . 15
LONGFORM_USERBANK . . . . . . . . . . . . . . . . . . . . . . . . 15
LFO_MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
LEAD_OFFSET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Custom Chords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
User Wavetable Creation . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Calibration 17
Appendix 18
Voicings Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Quality Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
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Description
Polyphony is back!
Chord v2 is a plug and play solution for bringing musical polyphony to your system. It
contains four oscillator voices, a multitude of waveforms, and intelligent tuning functionality.
This new version features an expanded sonic palette and feature set in half the size of the
original.
It features three primary modes of operation: Chord, Free Running, and Unison. These
three modes allow the oscillators to be tuned as diatonic chords, run independently of each
other, or be tuned to the same internal frequency for external v/oct sequencing through
independent CV inputs.
The timbral possibilities of the Chord v2 bring its polyphonic tones to life. The module ships
with eight banks of waveforms encompassing traditional shapes, vocal synthesis, organ
emulation, and chiptune sounds. You can also load custom wavetables using the SD card
slot on the front panel.
From harmonic drones to Switched On Bach, the Chord v2 is an unparalleled addition to
any Eurorack modular.
• Polyphonic oscillator
• Intelligent tuning system
• Independent output per voice + mix output(5 in total)
• Eight banks of waveforms
• SD card included
• Wavetables compatible with WaveEdit software by Synthesis Technology
Changes from v1:
• Half the size! 14HP down from 28HP
• Eight banks of waveforms
• Full polyphonic mode
• Harmonize in minor mode
• Custom wavetable compatibility
• Expanded chord types
• Improved synthesis engine
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Specifications
Depth: 23mm
Width: 14HP
Current Consumption:
• +12V: 122mA
• -12V: 25mA
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Installation
To install, locate 14HP of space in your Eurorack case and confirm the positive 12 volts and
negative 12 volts sides of the power distribution lines. Plug the connector into the power
distribution board of your case, keeping in mind that the red band corresponds to negative
12 volts. In most systems, the negative 12 volt supply line is at the bottom. The power cable
should be connected to the module with the red band facing the bottom of the module
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Marked Diagram
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Functional Overview
1. Frequency
Controls the frequency of the root note of the chord.
1a. Coarse Tune
7 Octaves of range
1b. Fine Tune
+/- a perfect fourth from center.
2. Bank
Controls which bank of wavetables is selected.
When the knob is turned, the LED bar at the top will indicate which bank is currently selected
for 750ms in white.
When the first bank is selected the LEDs will be dark,
When the last bank is selected the Asterick LED will be white.
When custom wavetables are being used, the LED bar will be backlit with a dim white.
CV Range: -5V to +5V.
CV is added to current knob position.
Factory Banks
1. Bandlimited Traditional Waveforms (Synthesized)
2. SawTooth through a Low Pass Filter (Synthesized)
3. FM (Wavetables)
4. Distorted (Wavetables)
5. Voice (Wavetables)
6. Square with with Pulse Width control (Synthesized)
7. Video Game (Wavetables)
8. Organ (Wavetables)
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Internal Wavetable Banks were created from the AKWF waveforms available at:
AKWF - Github
For more information on creating, and loading additional waveform banks see User Waveta-
bles section below.
3. Waveform
Controls the selected waveform within the current bank.
Waveforms are blended smoothly into each other.
Synthesized banks are rendered internally, and the Wave Knob/CV adjusts a parameter.
Wavetable banks are smoothly interpolated between to create smooth transitions between
unique tables.
CV Range: -5V to +5V.
CV is added to current knob position.
4. Linear FM
FM input with Attenuator
5. Voicing
Controls the inversion, and voicing of the chord. Adjusting the octave distances between
the different notes in the chord.
See Appendix 1 for a list of all voicings.
CV Range: -5V to +5V.
CV is added to current knob position.
6. Quality
Controls the quality of the chord, setting the relationship between each of the third, fifth,
and seventh outputs in relation to the root.
See Appendix 2 for a list of all voicings.
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CV Range: -5V to +5V.
CV is added to current knob position.
7. Mode
Controls the behavior of the Lead input Jack.
When the LED is off the Lead Jack is disabled.
When the LED is blue Melody mode is selected. The Seventh Output becomes a separately
controllable voice.
When the LED is green Free Poly Mode is selected. All four voices are fully independent.
When the LED is teal Unison Poly Mode is selected. All four notes are tuned together, but
each has their own V/oct input.
Melody Mode
When in Melody Mode, the lead jack controls the frequency of the seventh output.
The seventh output will be tuned to the same note as the fundamental frequency before any
1V/Octave input.
This allows for sequencing of an independent melodic sequence over a chord progression.
The inversions are still applied to the seventh output as if it were the seventh of the chord.
Free Poly Mode
When in Free Poly Mode the following changes are applied to the controls.
The Coarse knob and V/Oct CV control the Root frequency.
The Fine knob and Lead CV control the third.
The Voicing Knob and CV control the fifth.
The Quality Knob and CV control the Seventh.
Unison Poly Mode
When in Unison Poly Mode all four oscillators are tuned together, and can be adjusted with
the Coarse and Fine Frequency knobs.
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