see also:

• Korg Nautilus keyboard synth
• Korg Nautilus keyboard synth - Combinations
• Music
• digital audio workspaces (DAWs) / VST synths
• Roland XV-88 keyboard synth
• Nautilus manual (pdf)

• Individual “sounds” or “Timbres” are created as “Programs” which can consist of 1 or 2 individual sounds generated by one of the 9 built-in synthesizer engines and these are stored within banks as follows.
• Each program is either EXi (8 of the 9 synths) or HD-1 but cannot be a combination of each.
• Banks can contain either HD-1 Programs or EXi Programs, but not both, by default:
  • Banks A..E and P..R = EX sounds
  • Banks F..O, S,T, a..t = HD-1
  • GM = GM sounds
  • g(1)..g(9) = GM variations
  • g(d) = GM drum sounds

• When the knob is in the center, the settings are as programmed.
• Edits can be saved to the program using the normal Write Program procedure
• sound mode:
  • knob 1 = cc74 = filter cutoff frequency
  • knob 2 = cc71 = filter resonance
  • knob 3 = cc79 = filter EG intensity
  • knob 4 = cc72 = EG release time
  • knob 5 usually effects depth but can vary with program
  • knob 6 usually effects Reverb depth but can vary with program
• User mode allows user assignable controls

• You can assign a Tone Adjust parameter to each of the 16 switches and the 17 sliders on the Tone Adjust page.
• The available parameters depend upon the synth engine being used

• this allows the 2 sounds to be combined or split across the keyboard or velocity

• these include 8 of the 9 synths (excluding HD-1)

• 100 dual stereo note polyphony piano wave synth which allows wave files to be assigned to each note and one of 12 note velocities for each note
• multiple velocity layers of true damper resonance, along with modeled string resonance (this can be turned on/off via PROGRAM > SGX-2: String Resonance/Una Corda page, enable the String Resonance check-box)
• some sounds include dedicated Una Corda samples

• recreations of six classic tine and reed electric pianos, along with modeled vintage effects

• modeled organ with drawbar control

• different technology oscillators to HD-1 oscillators

• expansion of Korg’s classic MS-20 analog synth

• Based on the classic Korg Polysix analog synth but with added modulation of every control on the front panel and 180 voice polyphony, its timbre is distinctly different from the AL-1 and the MS-20EX
• self-oscillating four-pole filter, smooth analog oscillator and sub-oscillator, and rich, built-in chorus and ensemble effects
• well-suited to hands-on control with Tone Adjust for almost all of the original Polysix controls.

• Physical modeling for traditional instruments from guitars, basses, harps, and world/ethnic sounds to clavinets, harpsichords, bells, and electric pianos, and also NEW, unique experimental timbres
• can also process samples and live audio input through the physical model — including audio feedback from any of the NAUTILUS effects.

• Patch-panel VPM/waveshaping/PCM processor
• Combines Variable Phase Modulation (VPM), waveshaping, ring modulation, samples, and subtractive synthesis with a modular patch-panel system

• the sound of the HD-1 starts with one or more Multisamples which can be played directly, or use them through Wave Sequences, which play a series of different Multisamples over time to create rhythms or complex, evolving timbres.
• Single Programs have one oscillator, and Double Programs have two oscillators.
• Each oscillator includes a complete synthesis voice, with velocity-switched Multisamples, 2 filters, 3 EGs ( for Pitch, Filter, and Amplitude), 2 LFOs (in addition to a Common LFO), and, except for drum mode, each Oscillator has eight velocity zones, named MS1 (the highest velocity) through MS8 (the lowest). This means that the Program can play different Multisamples or Wave Sequences, depending on how hard you play. Each of the zones has separate settings for Level, Start offset and can fade into the next, to create smooth velocity transitions and can be layered two at a time.
• polyphony voices:
  • Double Programs use twice as many voices as Single Programs.
  • Wave Sequences use twice as many voices as Multisamples.
  • Stereo Multisamples use twice as many voices as Mono Multisamples, and Stereo Wave Sequences use twice as many voices as Mono Wave Sequences
  • If the X-Y Envelope is enabled, the number of voices used increases slightly.
• There are four main types of Multisample Banks you can choose from:
  • ROM - built-in factory sounds
  • SAMPLING mode - ones that you can see and edit in SAMPLING mode. May include Akai, SoundFont 2.0, AIFF or WAV files loaded from drive, or native NAUTILUS samples, and can be saved to User Sample Banks.
  • EXs - PCM expansion sets created especially for the NAUTILUS.
    • ROM Expansion is EXs1
    • Concert Grand Piano is EXs2
  • User Sample Banks
    • You can load and play gigabytes of your custom or converted samples at once, using Virtual Memory.
• Rev. (Reverse) lets you play the selected Multisample backwards, without looping. BUt does not apply to samples from EXs or User Sample Banks whose Load Method is set to Virtual Memory.
• Samples, Multisamples and Drum Samples are loaded by loading a .KSC file
• Wave sequences
  • Wave Sequences play back a series of different Multisamples over time and each have 64 “steps”, each step has a type, a multisample and various paramenters
  • Wave Sequences are similar to Drum Kits, in that you create and edit them in GLOBAL mode, and then use them in Programs.
  • In HD-1 Programs, you can use Wave Sequences just as you would normal Multisamples, including velocity switches or crossfades, layering different Wave Sequences on the two Oscillators, etc.
  • like drum kits, when you play a Wave Sequence in GLOBAL mode, it will use the settings from the previously selected Program or Combi.
    • Wave Sequence banks
      • wave sequences can be stored in banks (each contain up to 32 sequences) as follows:
        • A000..148, B00..K31, M00..N31, O00..T31 = factory presets (don't over-ride these as the HD-1 factory sounds will also change!)
        • user bank stores are A149, C13…31, I22…31, J06…J25, J30, J31, K19…31, M01…03, M07, M08,M11…31, N04…06, N16…31

• general architecture of program sound processing
  • Osc1 ⇒ Filter1 ⇒ Driver1 ⇒ Amp1 ⇒ combined oscillator output ⇒ Combined Equaliser
  • Osc2 ⇒ Filter2 ⇒ Driver2 ⇒ Amp2 ⇒ combined oscillator output ⇒ Combined Equaliser
  • Drum track ⇒ Drum Track Equaliser
  • Combined Equaliser outputs of the 2 oscillators combine with Drum Track Eq Output ⇒ IFX (each MIDI channel can have its own IFX settings) ⇒ MFX (MFX is bypassed if set to Dry) ⇒ TFX ⇒ audio outputs L/R
• Layer / Split sounds
  • how the two sounds in a program function across the keyboard and the note velocities
• Tone Adjust
  • interface for accessing the synth engine adjustable parameters
  • LFOs allow pitch (vibrato), filters (wah effects), volume (tremolo) and pan options as well as frequency of the LFO effect which can be synced to the system tempo, or varied using Alternate Modulation (AMS) sources such as another LFO, an EG or a controller
  • EGs (envelope generation)
    • HD-1's have EGs for pitch (eg. use to create a slight change when string is plucked), filter and amplitude
    • Start Level, Attack time, Attack level, Decay time, Break level, Slope time, Sustain Level, Release time, Release Level
  • Filter
    • allows adjustment of certain frequencies of the sound - each oscillator has two filters which can be used in series or parallel
    • eg. Low Pass, High Pass, Band Pass, Band Reject (reduces frequencies around the cutoff frequency), Resonance (emphasizes the frequencies around the cutoff frequency and may make it sound more nasal)
    • can modulate the filter via LFO1, LFO2, and the Common LFO. This can be used to create auto-WAH effect. JS-Y Intensity to A and JS-Y Intensity to B specify the depth of the wah effect produced by the LFO when the joystick is moved toward yourself, or when CC#2 is received. If SW1 is set to SW1 Mod. (CC#80) on the Set Up Controllers page, and AMS is set to SW1Mod. (CC#80), and the AMS Intensity is set to an appropriate value, an auto-wah effect is applied when you turn on SW1.
    • keyboard track allows making the sound more naturally brighter when higher pitch notes are played by increasing the cutoff frequency of a lowpass filter as you play higher on the keyboard.
    • works by creating four ramps, or slopes, between five keys on the keyboard.
  • Amp
    • each Oscillator has its own Amp section: Amp1 for OSC1, and Amp2 for OSC2.
    • allows volume level adjustments including keyboard tracking as for pitch, plus Drive Circuit to increase saturation such as for fattening the sound or overdrive distortion - Drive circuit ALWAYS is in play even with setting of 0 UNLESS you set BYPASS.
    • Low Boost is a special low-frequency EQ which controls the body character of the sound.
• Pitch bend
  • JS (+X) and JS(–X) settings specify the amount of pitch change (in semitones) that will occur when MIDI pitch bend messages are received or when the joystick is moved to left or right (max +/- 12 = +/-1 octave)
• Portamento
  • Time parameter = 0.00 means it is OFF, other values indicate how long it takes
  • can turn Portamento on and off via SW1 or SW2, by assigning them to Porta.SW CC#65.
• Effects
  • 197 available effects and thre is no maximum of how many of these can be used, although Smooth Sound Transition will only work if less than 34 are used, and you may wish to monitor the Performance Meters page to ensure you are not using too much processing power which may cause adverse effects on the sound.
  • each oscillator of a program as well as the program itself can be sent through up to 12 Insert Effects (IFX) in Series
  • In addition, there are two Master Effects (MFX) accessed through Sends 1 and 2 which are great for reverbs and delays
  • Then there are the two Total Effects (TFX) which process the main L/R outputs and best use with equaliser/compression or limiting effects
• Vector Synthesis
  • lets you control Program and Effects parameters by using the programmable X-Y Envelope set by X-Y pad on the display.
  • it can control the relative volume of the two Oscillators in PROGRAM mode
  • it can generate MIDI CCs for controlling Program and Effects parameters.