🎹 Saturn 9 Synthesizer

Professional Web-Based Synthesizer - User Guide v1.0

Copyright © 2025 Darron Hartas

📑 Table of Contents

1. Introduction

Welcome to Saturn 9, a professional web-based synthesizer that brings the warmth and character of classic 1980s analog hardware into your browser. Built entirely with the Web Audio API, Saturn 9 offers studio-quality sound design tools for music producers, sound designers, and electronic music enthusiasts.

🎯 Sound Generation & Voice Architecture

🎛️ Sound Shaping & Modulation

✨ Professional Effects Chain

🎼 Performance & Sequencing

🎹 MIDI Integration

💾 Presets & Sound Library

System Requirements

2. Getting Started

First Launch

When you first open Saturn 9, you'll need to click anywhere on the page to initialize the audio system. This is a browser security requirement.

💡 Tip: The status message will change from "Audio context suspended - click anywhere to enable audio" to "Saturn 9 Enhanced - Ready!" when the system is active.

Interface Overview

The Saturn 9 interface is organized into collapsible sections:

Playing Your First Note

  1. Click the Presets section header to expand it
  2. The default preset "A1: Jump Brass" is loaded
  3. Click on the virtual keyboard or press keys on your QWERTY keyboard
  4. Adjust the Master Volume in Settings (⚙️) if needed

QWERTY Keyboard Layout

Black Keys Q W E R T Y
White Keys A S D F G H J
↑ Back to Top

Ready to try Saturn 9?

🎹 Launch Synthesizer

3. Sound Engine

Signal Flow

OSC 1/2
→
Filter
→
Amp Env
→
Effects
→
Limiter
→
Output

Oscillators

Saturn 9 features two independent oscillators plus a sub-oscillator for rich, layered sounds.

Parameter Range Description
Waveform Sawtooth, Square, Triangle, Sine Basic tone shape - Sawtooth is brightest, Sine is purest
PWM 0-100% Pulse Width Modulation - varies square wave tone (only for square waves)
Level 0-100% Oscillator volume in the mix
Detune 0-100 cents Detunes OSC 2 relative to OSC 1 for chorus/beating effects
Sub Osc 0-100% Adds a sine wave one octave below OSC 1 for bass weight
Noise 0-100% White noise generator - useful for percussion and texture
💡 Sound Design Tip: Try detuning OSC 2 by 10-20 cents with both oscillators using sawtooth waves for classic analog-style thickness.

Filter

The multi-mode filter shapes the tone by removing or emphasizing frequencies.

Filter Types

Parameter Range Description
Cutoff 20Hz - 20kHz Filter frequency - where filtering begins
Resonance 0-100% Emphasizes frequencies at cutoff point - can self-oscillate at high values
Drive 0-10 Adds warmth and saturation - mimics analog filter distortion

Envelopes

Saturn 9 has two ADSR envelopes: one for amplitude (volume) and one for the filter.

ADSR Envelope Shape

Level Time A D S R Note ON Note OFF
Stage Description
Attack Time to reach full level after note on (0-2s)
Decay Time to fall from peak to sustain level (0-2s)
Sustain Level held while note is pressed (0-100%)
Release Time to fade to silence after note off (0-5s)
💡 Quick Settings:
• Pluck: Fast attack (0-10ms), low sustain (0-30%)
• Pad: Slow attack (300-1000ms), high sustain (70-100%)
• Percussion: Fast attack (0-5ms), zero sustain, short release

LFO (Low Frequency Oscillator)

The LFO creates cyclical modulation for vibrato, filter sweeps, and volume tremolo.

Parameter Description
Waveform Sine, Triangle, Square, Sawtooth, Random - shapes the modulation
Rate 0.1-20Hz - speed of modulation
Depth 0-100% - amount of modulation
Target Pitch (vibrato), Filter (auto-wah), Volume (tremolo)
↑ Back to Top

4. Effects

Effects Chain

Voice
→
Chorus
→
Delay
→
Reverb
→
Distortion
→
Limiter

Chorus

Dual-delay chorus effect that adds width and richness to your sound.

Delay

High-quality feedback delay with lowpass filtering for natural repeats.

Reverb

Convolution reverb with procedurally generated impulse responses.

Distortion

Musical waveshaping distortion with 2x oversampling for clean harmonics.

⚠️ Note: The Output Limiter (in Settings) prevents clipping when using high effect levels or playing loud chords. Keep it enabled for protection.
↑ Back to Top

5. Performance Controls

Voice Mode

Portamento

Glide time between notes in mono mode. Range: 0-2s. Higher values create dramatic pitch slides.

Pitch Bend & Mod Wheel

Control via MIDI controller or mouse:

Hold Function

Press the HOLD button to sustain all currently playing notes indefinitely. Press again to release. Perfect for building drone sounds or playing over a sustained chord.

↑ Back to Top

Experience the performance controls yourself

🎹 Launch Synthesizer

6. Sequencing & Rhythm

Arpeggiator

The arpeggiator automatically plays arpeggios from held notes.

Patterns

Parameters

Parameter Description
Rate 1-20 notes per second - arpeggio speed
Octaves 1-3 octaves - range of arpeggiation
Gate 10-100% - note length as percentage of step time

Drum Machine

Built-in rhythm section with 17 EDM-focused patterns across 16 steps.

Patterns Include

Controls

💡 Production Tip: The drum machine is perfect for jamming and sound design. Record your performance with the looper while the drums play!
↑ Back to Top

7. Presets & Sound Design

Preset Navigation

Saturn 9 includes 112 factory presets organized into 7 banks (A-G), plus unlimited user presets.

Quick Navigation

Preset Banks

Bank Category Description
Bank A Brass & Poly Brass Classic 80s brass sounds - Jupiter, Prophet, OB-style
Bank B Strings & Pads Lush ensemble strings and evolving pads
Bank C Keys & Poly Comps Electric pianos, bells, and composite sounds
Bank D Organs & Choirs Combo organs and synth choirs
Bank E Bass Moog-style bass, funk bass, sub bass
Bank F Leads Solo leads, sync leads, aggressive tones
Bank G FX & Percussion Sound effects and percussive sounds

Saving User Presets

  1. Design your sound using the controls
  2. Click the 💾 Save button in the Presets section
  3. Enter a name for your preset
  4. Your preset is saved to browser localStorage

Import/Export

⚠️ Important: User presets are stored in your browser's localStorage. Clearing browser data will delete your presets. Export important sounds!
↑ Back to Top

8. MIDI Integration

Connecting a MIDI Device

  1. Connect your MIDI keyboard/controller via USB
  2. Refresh the Saturn 9 page
  3. Your device should appear in the MIDI device list
  4. Select your device from the dropdown
  5. Select MIDI channel (or "All" for omni mode)

MIDI Features

Velocity Sensitivity

Saturn 9 responds to MIDI keyboard velocity in two ways:

Volume Response

Key velocity directly controls note volume - soft touches produce quieter sounds, hard hits produce louder sounds. This is always active and provides natural dynamic expression.

Filter Velocity Sensitivity

The Velocity Sensitivity rotary knob in the Filter section controls how much key velocity affects filter brightness:

How it works: Soft key presses (low velocity) close the filter for darker tones, while hard key presses (high velocity) open the filter for brighter tones. This creates an organic, dynamic playing experience similar to acoustic instruments.

💡 Production Tip: For expressive leads and keys, set Filter Velocity Sensitivity to 2000-3000 Hz. For pads and ambient sounds, keep it low (0-500 Hz) for consistent timbre. Bass sounds work great with 1500-2000 Hz for attack variation.

CC Mapping

Map MIDI controllers to Saturn 9 parameters:

  1. Expand the MIDI CC Mapping section
  2. Click Learn next to a parameter
  3. Move the controller on your MIDI device
  4. The mapping is automatically created
  5. Click Clear to remove a mapping

Aftertouch Configuration

In Settings (⚙️), configure how aftertouch affects the sound:

💡 Tip: For expressive leads, try setting Filter Cutoff to 70% and Vibrato to 50%. Press harder for brighter, more vibrato-rich notes.
↑ Back to Top

Test MIDI features with your controller

🎹 Launch Synthesizer

9. Recording & Looping

Recording Modes

Saturn 9 features a dual-mode looper:

Simple Recording Mode

Loop Mode

Looper Controls

Button Function
REC Start recording or add overdub
PLAY Playback recorded audio
STOP Stop playback/recording
CLEAR Delete all recorded audio
UNDO Remove last overdub (Loop Mode only)

Exporting Audio

  1. Record your performance
  2. Click Download to export as WAV file
  3. Import into your DAW for further production

Quantize Settings

In Settings (⚙️), set quantize subdivision for overdubs:

💡 Workflow Tip: Start your loop with drums from the Drum Machine, then layer synth parts on top. Use UNDO to experiment with different overdubs!
↑ Back to Top

10. Settings & Configuration

Access Settings by clicking the ⚙️ icon in the top-right corner.

General Settings

Audio Settings

Recording Settings

MIDI Aftertouch

⚠️ Note: Settings are saved automatically to browser localStorage. Click Save to confirm changes or Cancel to revert.
↑ Back to Top

11. Keyboard Shortcuts

Preset Navigation

Previous Preset ← Left Arrow
Next Preset → Right Arrow

QWERTY Keyboard (when enabled)

Black Keys (C#-D#-F#-G#-A#) Q W E R T Y
White Keys (C-D-E-F-G-A-B) A S D F G H J
Octave Down Z
Octave Up X

Looper Controls

Record / Play / Overdub L
Stop Playback/Recording K

Modal Windows

Close Settings/Help/Browser ESC
↑ Back to Top

12. Troubleshooting

No Sound

Solution:
  1. Check if status says "Audio context suspended" - click anywhere on page
  2. Verify Master Volume in Settings is not at 0%
  3. Check browser's site permissions allow audio
  4. Ensure oscillator levels are not at 0%
  5. Try a factory preset to verify system is working

MIDI Not Working

Solution:
  1. Ensure MIDI device is connected before loading page
  2. Refresh the page after connecting MIDI device
  3. Check MIDI device is selected in dropdown
  4. Verify MIDI channel matches your controller
  5. Try "All Channels" if unsure of device channel

Audio Crackling/Popping

Solution:
  1. Reduce Master Volume in Settings
  2. Enable Output Limiter in Settings (should be ON by default)
  3. Lower effect levels (especially Distortion Drive)
  4. Close other browser tabs using audio
  5. Reduce number of simultaneous voices in Poly mode

Lost User Presets

Prevention:

User presets are stored in browser localStorage. They can be lost if you:

Always export important presets using the Export button!

Performance Issues

Solution:
  1. Close other browser tabs and applications
  2. Use Mono voice mode instead of Poly
  3. Disable effects you're not using
  4. Reduce reverb room size
  5. Use a modern browser (Chrome, Firefox, Edge)

Recording Issues

Solution:
  1. Ensure browser has microphone permissions (even though we're recording internal audio)
  2. Try Simple Recording mode instead of Loop Mode
  3. Clear existing recording before starting new one
  4. Reduce recording length for better performance

Browser Compatibility

Saturn 9 requires Web Audio API support. Recommended browsers:

↑ Back to Top

Start creating music now!

🎹 Launch Synthesizer

Saturn 9 Synthesizer - Professional Web-Based Synthesizer

Home • About • Launch Synth • Disclaimer & Terms

Copyright © 2025 Darron Hartas

For support and updates, visit the project repository
Version 1.0 - User Guide Last Updated: October 2025