Qu-Bit Electronix Nebulae User manual

DUUUUUUUUUURRRM
Drum Machine Alternate Instrument
For QuBit Nebulae v.2 - By Eli Pechman
Durm is a four voice drum machine where all of the voices share the
same parameters as set by the front panel controls. There are two
ways around this: drum settings are only updated for each voice
when a trigger for that voice is received, meaning that with fast
enough modulation each voice will have settings that differ from
the other voices. The other possibility is to "lock" the parameters
for the given voice, causing the front panel controls and relevant
modulation to no longer have an effect on that particular drum voice.
This enables the user to tweak the settings for each drum voice to
their liking and then have the option to only modulate the 'unlocked'
voices. The "speed" knob controls an effect that is shared over all
of the voices with one of four effects being selected by an alternate
control. All parameters (except for window, pitch and speed) can be
randomized per step with a set randomness amount. Audio inputs are
routed through the main effect and also through a side chain comp-
ression sort of effect controlled by the internal synthesizer envel-
opes. Bass drum is always routed to the left channel and all other
drums are routed to the right. Controls for each voice are as follows.

Bass Drum Settings
Triggered by "Record" Input
Pitch Envelope
Decay (exponential
envelope)
Pitch Env.
Modulation
Amount
Non-linearity
Amplitude
Ebvelope
Decay
Brightness
Distortion
Pitch
The bassdrum consists of 3 sine wave
oscillators that are all ring-modulated
and then sent through a low-pass filter.
"Nonlinearity" controls a sort of detune
for each of the oscillators as well as
an overdrive of the filter.

Snare Drum Settings
Triggered by "Next" Input
Pitch Envelope
Decay (exponential
envelope)
Pitch Env.
Modulation
Amount
Noise feedback
AMplitude
Ebvelope
Decay
Brightness
White noise
mix in
Pitch
The snare drum is a clocked noise source
being fed into a filter. The feedback
knob sends the output of the noise sample
and hold into the clock frequency over the
first half of the knob and into the filter
cutoff frequency over the second half.
Pure white noise can be fed in with the
window knob.

High Hat Settings
Closed High hat triggered by "Source" Input
Amplitude envelope
to pitch modulation
amount.
Oscillator
spread
Wave (sin/ square)
Amplitude
Envelope
Decay, closed
high hat is
1/10th open
high hat length
White noise
low pass cutoff
White noise
high pass
amount.
Pitch
The high hat is a set of ring-modulated
oscillators and white noise with both
high pass and low pass controls. The closed
high hat decay is a preset fraction of the
length of the open high hat decay (roughly
1/10th). Window works in the opposite
direction of how a high pass filter is normal-
ly configured to work nicely with the window
knob response on other drums.
Open High hat triggered by "Reset" Input

Percussion Drum
Triggered by the "Freeze" input
Harmonic ratio
numerator
Harmonic
ratio
denominator
Modulation
Amplitude
envelope
decay
Brightness
Waveform
Base
Pitch
The percussion drum is a four operator phase
modulation voice with operator frequencies
set by an integer numerator/ denominator ratio.
The 'blend' knob will increase phase modulation
amount from each operator to the next, waveform
crossfades between a sine wave and a tangent
(similar sound to a saw tooth). Brightness
controls cutoff frequency of a low pass filter.

Alternate Settings
Start parameter
randomness amount
Density
parameter
randomness
amount
Blend parameter
randomness amount
Size
parameter
randomness
amount
Overlap
parameter
randomness
amount
Overall
effect
select
Bass drum
pitch range
In this page we get the "hidden" drum settings
accessed by holding the source button. All drums
can have their settings frozen by pressing the
button associated with the desired drum (reset
for both highhats). 'Next' and 'reset' buttons
do not display the freeze state of the drums due
to the nature of the nebulae so a few attempts may
need to be made to correctly freeze these drums.
The alt-pitch knob controls the range of the bass
drum to keep it in a lower register than the other
drums. All of the other parameters (except window
and speed) can have a per-step randomness amount
set by turning their knobs with source held. The
randomness is added to the base parameter value
across all unfrozen drums. Alt-window changes the
shared effect for the drums.
Audio input
gain
Freeze drum
params

Effects overview
All of the drums have one global effect that is
controlled by the 'speed' knob. There are four
effects which can be selected between by pressing
the source button and turning the window knob.
All four effects do something different when the
speed knob is left of center versus right of
center, indicated by the two LEDs next to the
speed knob. The durm program boots with the
trigger randomizer by default.
trigger
randomizer
Compand/
distort
Dj style
filter
Dj style
downsampler
Trigger randomizer
Compand - distort
Dj style filter
Dj style downsampler
random skip
compress
low pass
downsample
random ratchet
expand/ distort
high pass
high pass sample