Cerebrum v3.5
by Psychic Modulation
part of the NeurosynthPack
Designed by Jack Resweber using SynthEdit

Contents

1. Introduction
2. Getting Started
3. Drum/Bass Mixer
4. Sequencers
  4.1 Central Core
  4.2 Assignments and Options
  4.3 Beat Matcher, Randomization, Sequence Behavior and MIDI Options
  4.4 Sequence Length and Position
  4.5 Bass Sequencer
5. Synth Modules
  5.1 Kick Drum
  5.2 Snare Drum
  5.3 HiHat
  5.4 Percussion Synth Drum (Perc1)
  5.5 Percussion Sample Drum (Perc2)
  5.6 Amp Envelope/Stereo Position
  5.7 Sample-Based Synths
  5.8 Bass Synth
  5.9 Bass LFO
6. MIDI Controls
Credits

1. Introduction
Cerebrum is a hybrid groovebox-style drum machine featuring five drum modules as well as a bass synth module, each with it's own dual A/B sequencer for beat-matching. Designed with live operation in mind, Cerebrum can be used for making complex beats on the fly that can be randomized, mixed, matched and manipulated in a number of ways.

2. Getting started
When Cerebrum is first loaded into your host, you should first decide how you want to run it. You have a few options:
Manual- If you just want to make some quick beats, you can run it manually without following the host sequencer, simply press the play button. If anything becomes out of sync for any reason, just click the reset button.
Host Sync- If you are using Cerebrum in a song, and want it to start when your host sequencer starts, switch on the 'Host' button and then press the play button. Now Cerebrum is set to start when you start the host sequencer. It will also stop when the host is stopped. A useful trick for getting solid timing is to click the reset button before starting your host for the first time. This will make Cerebrum's sequencers snap to the first bar, insuring that it starts out and stays on-beat.
MIDI Trigger- Cerebrum can also be triggered via a MIDI device such as a keyboard. It's already set up for this, so you can simply press a key at any time. Each sequencer has it's own midi trigger options for asigning which key triggers the sequencer on which octave. The bass sequencer can be triggered by the higher or lower octaves. Cerebrum is defaulted to trigger the drum sequencers on the upper keys, and the bass sequencer on the lower, but this can be changed if needed. The middle keys are setup to trigger the drums as one-shots.

1. Play Button (MIDIcc23)
   Starts/stops Cerebrum's sequencers
   *note-This button will only work on it's own if Host Sync is deactivated
2. Host Sync
   When activated along with the play button, Cerebrum will start/stop according to the host sequencer's transport controls; will run or stop depending on if you press play or stop in your host app.
3. Reset (MIDIcc14)
   This button will resets all sequencers; in host mode, it will reset all sequencers at the beggining of the next bar. This is a usefull feature for keeping Cerebrum on beat.
   *note- a usefull trick, if you have problems with Cerebrum being out of sync with the host upon startup, is to press the reset button before pressing play in your host. This will reset the sequencers to the first bar before it is started, insuring that it starts out and stays on-beat.

3. Drum/Bass Mixer
The drum mixer provides the main volume controls(MIDIcc 24-31) for quick drum mixing. When a synth module is triggered, it's volume knob will light up. This can be useful in figuring out which module is playing at a given time. Each module can also be muted or soloed as well as routed to different output channels via this section.

1. Module Selector
   When selected, will display the chosen synth module's controls as well as sequencers
2. Volume Control
   Adjusts the overall volume of each synth module
3. Mute/solo switches
   Each module has it's own mute/solo switches.
4. Output Channel
   Selects the audio output channel of each module (Channels 1-6)
5. Main Volume
   The main volume control for adjusting the overall level of Cerebrum's output (MIDIcc-7)

4. Sequencers
Each of the synth modules has it's own dual 16-step sequencers which allow switching between two different beats, manually or automatic. The sequencers are very flexible, and can be played in a variety of ways including looped or ping-pong. There are two sets of assignable accent underscores for things like volume accents, glide, glitch, sample reverse and sample gating. There's also two sets of assignable velocity grids, for level, pitch, filter, decay and glitch rate. Velocity can be altered quickly by simply dragging the mouse accross the grid. Each sequencer also hosts four types of randomization for further beat manipulation.
Below is an in-depth look at the sequencers controls and options. This guide is split into three sections, each focusing on a different portion of the sequencer. Further down is a detailed explanaition of the bass sequencer which is different from the rest because of it's note-grid.
4.1 Sequencer Central Core
This chart displays the core of the sequencer, which is made up of two switchable sequence patterns, as well as two sets of assignable accent underscores and velocity controls.

1. Sequencer-A
   Default sequence to start with; if a sequence is lit up, then it's activated, if it is darkened then it's deactivated.
2. Sequencer-B
   Move the slider down to switch to this sequence
3. Accent 1
   Displays the first set of assignable underscore accents
4. Accent 2
   Displays the second set of assignable underscore accents
5. Velocity 1
   Displays the first assignable velocity grid. Slide the mouse across the grid to adjust the controls
6. Velocity 1
   Displays the second assignable velocity grid. Slide the mouse across the grid to adjust the controls
7. Active Step
   Click on this grid to place a step into the sequence. Click it again to remove the step.
8. Active Accent
   Click on this grid to place an accent under each step. Click it again to remove the accent.
9. Velocity Level
   Drag the mouse accross this grid to alter the velocity levels under each step.

4.2 Sequencer Assignments and Options
This portion of the sequencer section displays options for accent and velocity assignments, velocity level controls and other options.

1. Sequencer Activation
   Powers the sequencer; when deactivated, the sequencer will be bypassed. This can be useful to preserve cpu when not using a sequencer, for instance, if only the one-shot drum was being used.
2. Sequence Rate
   Selects the rate or speed of the sequence
3. Sequence Pause
   Pauses/resumes the sequence
4. Accent 1 Choice
   Gain- Applies a volume boost with each accent
   Reverse- For use only with the wavlayer, this will reverse the sample with each accent
   WavGate- For use only with the wavlayer, this will gate the volume of the sample with each accent, great for gating long samples like pads or loops.
   The following apply to the bass sequencer only:
   Octave- Each accent will raise the active step one octave
   Filter- Each accent will raise the filter cutoff slightly for the active step
5. Accent 2 Choice
   Glitch- Produces fast, tight rolls for each accent; the rate of these rolls can be adjusted with the velocity controls, when assigned to "GlitchRate".
   Glide- Glides a set of steps together when accented. When steps glide, they are considered mono, and the pitch can be bent with velocity sliders. The "Glide" control specifies the portamento between each step.
6. Glide Control
   When accent 1 is set to "glide", this will determine the portamento of the pitch or filter between each gliding step.
7. Velocity 1 Choice
   Pitch- The velocity grid controls the pitch of each step
   Level- The velocity grid controls the level or volume of each step
   Filter- For Snare1/Hihat only; The velocity grid controls the filter cutoff of each step
   Mod- For Perc1 only; The velocity grid controls the modulation of each step
8. Velocity 1 Level
   Adjusts the level of velocity defined by the velocity grid
9. Velocity 2 Choice
   GlitchRate- The velocity grid controls the glitch rate of each step; meaning when accent 2 is assigned to glitch, this will adjust the rate or speed of the rolls.
   Pitch- The velocity grid controls the pitch of each step
   Decay- The velocity grid controls the decay and release of each step
10. Velocity 2 Level
    Adjusts the level of velocity defined by the velocity grid

4.3 Beat Matcher, Randomization, Sequence Behavior and MIDI Options

1. Sequence indicator
   Indicates which sequence is currently active
2. Beat-Matcher
   Move this slider up or down to switch between sequence A and B
3. Auto-Mix Activation
   Activates the Auto-Mix function, which automatically switches between sequence A and B.
4. Auto-Mix Rate
   Selects the Auto-Mix rate (BPM-Synced)
5. Auto-Mix Path
   Selects whether the auto-mix path is from A-B or B-A
6. Auto-Mix Phase
   Adjusts the phase of auto-mixing; defines the length of time for seq A to switch to seq B and vice versa.
   For example: If phase is set to '0', then seq A switches to seq B for the same amount of time, depending on the rate setting. The more the phase control is moved to the left, the shorter the time it remains on B. The more it is turned to the right, the shorter the time sequence A is active. The 'phase' control reverses this.
7. Randomization Type
   Selects the type of randomization:
   Speed- Randomizes the sequence speed, creating a stuttering effect when stopped on an active step.
   Position- Randomizes the position of the sequence, for unpredictable randomization.
   AutoRate- Randomizes the rate of the Auto-Mix function.
   AutoPhase- Randomizes the phase of the Auto-Mix function.
8. Random Probability
   Adjusts the amount of sequence randomization; the higher the level, the more likely somthing will get randomized.
9. Sequence Type
   Selects the sequence type:
   One Shot- plays the sequence once from start to end, until restarted
   Loop- loops the sequence until stopped
   Ping-Pong- Bounces the sequence from start to end, back to start and so on
   The following controls are for use when playing the sequencer via MIDI keyboard:
10. Octave
    Selects the octave that will trigger the sequencer.
11. Note
    Selects the note that will trigger the sequencer.
    *note* The bass sequencer can be played on a range of keys; it's midi options allow selecting to play on higher or lower octaves, and a switch for choosing retriggered or legato play.

4.4 Sequence Length and Position
The sequencers position/length can be adjusted by dragging the start/end points. These points arent visible until dragged with the mouse, so this usefull function can be easily overlooked.

1. Sequence Start Position
   Indicates the starting point of the sequence, to adjust, simply click just to the right of the position bar and drag to the right or left.
2. Sequence End Position
   Indicates the ending point of the sequence, to adjust, simply click just to the left of the position bar and drag to the left or right.
3. LED Indicator
   Indicates what step is being played during the sequence.

4.5 Bass Sequencer
The bass sequencer is different from the other sequencers, with a note grid instead of velocity grids.

1. Note Display
   Displays which note is assigned to each row.
2. White Keys
   White rows represent the white keys on a keyboard.
3. Black Keys
   Black rows represent the black keys on a keyboard.
4. Active note
   Orange lit notes represent the active note in the sequence; to activate a note, simply click anywhere on the note grid.

5. Synth Modules
Cerebrum uses 6 modules, 5 for drums and 1 for bass. Each drum module has it's own individual control panel consisting of a drum synth as well as a small sample-based synth for layering with built-in kick, snare and percussion samples. The bass module consists of a flexible bass synthesizer with onboard LFO. Each module has a switch for randomizing a selection of controls on each module. Here's a brief walk-through of each module and their different functions:
5.1 Kick Drum Module

1. Waveform
   Selects the waveform of the drum: sine, triangle or even pulse for a more abrasive sound
2. Pitch
   Overall pitch of the oscillator
3. Pitch Envelope
   Adjusts the pitch envelope level; higher levels produce a more defined drum
4. Pitch Follow
   Pitch sustain; adjusts the point where the pitch follows from the decay to the initial pitch setting.
5. Pitch Decay
   Adjusts the decay rate of the pitch envelope, for defining the drum curve
6. Waveshaper Activation
   Powers the waveshaper on/off
7. Pre Gain
   Adjusts the level of gain applied before limiting
8. Limiter
   Limits the signal of the drum into light distortion
9. Cut
   Cutoff frequency of the post-limiter filter
10. Frequency
    Adjusts the low frequency EQ
11. Boost
    Boosts the EQ level

5.2 Snare Drum Module

1. Waveform
   Selects the waveform of the drum: sine, triangle and even pulse for a more abrasive sound
2. Pitch
   Overall pitch of the tone oscillator
3. Pitch Envelope
   Adjusts the pitch envelope level; higher levels produce a more defined drum
4. Pitch Decay
   Adjusts the decay rate of the pitch envelope for defining the drum curve
5. Tone Amp Decay
   Adjusts the amp decay rate of only the tone; for fattening up the snare.
6. Rattle
   Produces a rattling effect by sending the noise's output through the tone oscillator
7. Osc/Noise Mixer
   Crossfades between the tone and noise oscillators
8. Noise Color
   Chooses the noise color:
   White for a light, airy noise
   Pink for a darker, heavy noise
9. Filter Type
   Chooses the filter type: LP, HP, BP1, BP2, BR
10. Resonance
    Filter resonance
11. Frequency
    Cutoff frequency
12. Filter Velo
    Adjusts the velocity of the filter envelope
13. Filter Envelope Level
    Adjusts the filter's envelope level
14. Filter ADSR
    Attack, Decay, Sustain and Release controls for the filter envelope

5.3 HiHat Module

1. Waveform
   Selects the waveform of the drum
2. Pitch
   Adjusts the pitch of the pulse tone
3. D-Tune
   Detunes the FM oscillator
4. FM Level
   Adjusts the FM level of the pulse tone
5. Pulse Width
   Adjusts the width of the pulse tone for a more spread out sound
6. Tone/Noise Mixer
   Crossfades between the tone and noise oscillators
7. Noise Color
   Chooses the noise color:
   White for a light, airy noise
   Pink for a darker, heavy noise
8. Filter Type
   Chooses the filter type: LP, HP, BP1, BP2, BR
9. Frequency
   Cutoff frequency of the noise filter
10. Resonance
    Filter resonance
11. Filter Velo
    Adjusts the filter velocity
12. Filter Activation
    Powers the filter on/off

5.4 Percussion Drum Synth Module (Perc1)

1. Type
   Selects whether the drum has a 'wood' or 'metal' type sound
2. Pitch
   Overall pitch of the oscillator tone
3. Height
   Adjusts the pitch height, giving a sharp initial 'hit'
4. Pitch Follow
   Pitch sustain; adjusts the where the pitch follows from the hieght to the initial pitch setting.
5. Noise
   Lets in a subtle noise for adding air to the drum
6. Dim
   Dims the cutoff frequency of the noise
7. FM
   Frequency Modulation: Inputs a 2nd oscillator for modulating the carrier tone
8. PM
   Pitch Modulation: Routes the modulation oscillator into the carrier's pitch
9. Freq
   Adjusts the overall rate of the modulation oscillator
10. Sub
    Adjusts the sub-rate of the modulation oscillator; sets the rate really low; good for producing phone ring type sounds and FX
11. Dull
    Dulls the modulation; good for reducing the definition of modulation
12. Depth
    Overall modulation depth; adjusts the overall level of modulation

5.5 Sample Layers
Each drum module has it's own sample-based synth for layering with sampled drums. Samples can be mixed with the output of the drumsynth via the small overhead mixer.

1. Drumsynth mix level
2. Sample mix level
3. Randomization
   Randomizes a selection of controls on each module
4. Selects a sample from a dropdown list
5. Pitch
   Overall pitch of the sample
6. Decay
   Controls the decay of the sample
7. Velo
   Adjusts the amount of velocity of the sample when triggering as a one-shot
8. Filter
   Lo cut filter control for the sample

5.6 Percussion Drum Sample Module (Perc2)

1. Sample
   Selects a sample from a dropdown list
2. Pitch
   Overall pitch of the sample
3. Attack
   Adjusts the pitch attack, giving an initial warping of the sound
4. Decay
   Adjusts the pitch decay, giving a sharper sound to the sample
5. Level
   Adjusts the level of the pitch envelope; determines how defined the attack and decay will be
6. Filter Type
   Selects the type of filter
7. Filter Activation
   Switches the filter on/off
8. Filter Cutoff
   Adjusts the filter cutoff level
9. Filter Reson
   Adjusts the filter resonance
10. Sample Level
    Mixes in the sample to the overall sound
11. Wav Level
    Mixe in the user wav to the overall sound
12. Wav Activation
    Overall modulation depth; adjusts the overall level of modulation
13. Wavfile
    Selects a user wavfile from your harddrive for layering with the sample synth
14. Pitch
    Adjusts the pitch of the user wavfile
15. Reverse
    Reverses the wavfile
16. Start/End Positions
    Adjusts the start/end positions of the wavfile

5.7 Amp Envelope/Stereo Position
Here is another section common to all modules, which displays the amp envelope and panning/gain vector:

1. ADSR
   Attack, decay, sustain and release controls for the amplitude envelope
2. Mono/Poly Switch
   Selects wether the synth is mono or poly; mono will reset the synth at each active step, poly will allow steps to overlap.
3. Amp Velocity
   Adjusts velocity of the amp envelope
4. Pan/Gain Vector
   left-right: panning
   up-down: gain

5.8 Bass Synth Module

1. Oscillator-1 Waveform (Phase Distortion)
2. Osc-1 Octave
3. Osc-1 Tune
   Fine-tunes oscillator 1
4. Osc-1 level
5. Phaz Level
   Adjusts the level of phase distortion of oscillator 1
6. Sync
   Syncs the pitch of osc 1 & 2
7. FM
   Adjusts the level that osc 1 modulates osc 2
8. Oscillator-2 Waveform
9. Osc-2 Octave
10. Osc-2 Tune
    Fine-tunes oscillator 1
11. Osc-2 level
12. Pulse Width
    Adjusts the width of the pulse waveform, when in use
13. Filter Activation
    Powers the filter on/off
14. Filter Type
    Chooses the filter type: LP, HP, BP1, BP2, BR
15. Filter Env Inversion
    Inverts the filter envelope
16. Filter Envelope Level
    Adjusts the filter's envelope level
17. Filter Velocity
    Adjusts the velocity of the filter envelope
18. Filter ADSR
    Attack, decay, sustain and release of the filter envelope
19. Filter Cutoff Frequency
    Adjusts the filter's cutoff frequency
20. Filter Resonance
    Adjusts the filter's resonance
    5.9 Bass Synth LFO
    The bass synth also has an LFO section for modulating the filter or oscillator pitch, or even both for gritty synced filter sweeps.

1. LFO Activation
   Powers the LFO on/off
2. LFO Target
   Selects the target for modulation (Filter, Osc2 Pitch, or both)
3. LFO Rate
   Adjusts the rate of the LFO (BPM Synced)
4. LFO Shape
   Selects the shape of the LFO path
5. LFO Level
   Adjusts the level of the LFO
6. LFO Reset
   LFO will follow sequencer, resetting each time

6. MIDI Controls
Other assignments:
Kick-SeqMixer:114
Snare-SeqMixer:115
Hihat-SeqMixer:116
Perc1-SeqMixer:117
Perc2-SeqMixer:118
Bass-SeqMixer:119

Credits
Many thanks to the following for providing the tools to aid in the creation of this VSTi:
Chris Kerry - mod osc / arp / midi / FX modules
www.chriskerry.f9.co.uk
David Haupt - filter / wavplayer / sub-control modules
www.dehaupt.com/SynthEdit
Dan Worall - sequencer modules
Les Production Zvon - (ZV)Samples
www.lesproductionszvon.com
Manytone Music - (MT)Samples
www.manytone.com
Jeff McClintock - SynthEdit
www.synthedit.com
Steinberg - VST Plugin Technology