O-AnalogSaturation User Guide

Getting Started

Download & Install

Download the installer for your platform:

• macOS Installer (Universal — Intel & Apple Silicon)
• Windows Installer (64-bit)

Quick Start

1. Run the installer — it installs both VST3 and AU formats automatically
2. Open your DAW and scan for new plugins
3. Insert O-AnalogSaturation on a track
4. Select a saturation model (Magnetic, Tube, Transformer, or Diode)
5. Turn up the Intensity knob to taste

System Requirements

Installation Paths

macOS:

• VST3: ~/Library/Audio/Plug-Ins/VST3/O-AnalogSaturation.vst3
• AU: ~/Library/Audio/Plug-Ins/Components/O-AnalogSaturation.component

Windows:

• VST3: C:\Program Files\Common Files\VST3\O-AnalogSaturation.vst3

Interface Overview

O-AnalogSaturation features a vintage botanical-themed interface with a central intensity knob, model selection buttons, and dual VU meters. The decorative snake illustration changes with each saturation model and responds to the intensity setting.

Layout

• Top row: Four model selection buttons — MAGNETIC, TUBE, TRANSFORMER, DIODE
• Center left: Large Intensity knob with value display
• Center right: Snake illustration (changes per model, opacity tied to intensity)
• Left & right meters: Input and Output VU meters with green-to-red gradient needles
• Bottom left: Quality selector — LOW, MID, HIGH
• Bottom right: Autogain toggle

Knob Interaction

• Vertical drag: Click and drag up/down to adjust the Intensity knob
• Shift + drag: Fine-tune with smaller increments
• Double-click: Reset to default value

Visual Feedback

The snake illustration provides visual feedback tied to the current state:

• Each saturation model displays a different botanical snake illustration
• The snake’s opacity increases with the Intensity knob (subtle at low settings, prominent at high settings)
• The central dial shows the current intensity value

Saturation Models

O-AnalogSaturation offers four physically-modeled saturation algorithms, each based on a different analog circuit. Select a model using the buttons at the top of the interface.

MAGNETIC

Based on the Jiles-Atherton tape hysteresis equations, simulating actual magnetic tape recording behavior.

• Smooth, warm compression with subtle harmonic generation
• Natural “memory” effect from hysteresis — sound depends slightly on what came before
• Gentle high-frequency saturation that softens transients
• Head bump around 80–100 Hz, subtle HF rolloff above 12 kHz

Best for: Adding tape-style warmth and glue to full mixes, drums, and vocals.

TUBE

Mathematical model of triode vacuum tube behavior (12AX7 character), including plate current characteristics and grid voltage response.

• Rich even and odd harmonic generation
• Asymmetric clipping — different behavior for positive and negative swings
• Musical compression that “breathes”
• Upper-mid presence boost around 3 kHz

Best for: Vocals, guitars, bass — anywhere you want musical harmonic richness and presence.

TRANSFORMER

Iron core transformer saturation modeling with magnetizing inductance, core nonlinearity, and frequency-dependent behavior.

• Low-frequency thickening and “weight”
• Subtle resonant coloration at low-mid frequencies
• Soft limiting that controls peaks naturally
• LF bump at 60 Hz, gentle HF sheen around 8 kHz

Best for: Adding console-style punch and glue to buses, drums, and master chains.

DIODE

Accurate diode junction modeling using the Shockley equation, solved iteratively with Newton-Raphson for precise soft-clipping behavior.

• Edgier, more aggressive saturation character
• Symmetric soft clipping with a defined “edge”
• Clear harmonic structure that cuts through mixes
• Relatively flat frequency response

Best for: Adding grit and edge to guitars, synths, and parallel distortion chains.

Parameters

Parameter Details

Intensity

The Intensity knob is the primary control. It simultaneously adjusts the drive level into the selected saturation model and the dry/wet mix. At 0%, the signal passes through with minimal coloration. At 100%, the full saturation character is applied. The knob uses linear scaling for predictable, musical response across the full range.

Quality

The Quality setting controls the tradeoff between CPU usage and audio fidelity:

• LOW: No oversampling. Lowest CPU usage (<1%). Best for live performance and tracking.
• MID: 2x oversampling with polyphase filters. Balanced CPU (~2–3%). Good for general mixing.
• HIGH: 4x oversampling with high-quality anti-aliasing and ADAA. Highest CPU (~5–8%). Best for mastering and final renders.

Autogain

When Autogain is enabled, the plugin automatically compensates the output level so that increasing the Intensity knob doesn’t make the signal louder. This lets you judge the tonal character of the saturation without being fooled by volume differences. The compensation uses a slow RMS envelope (~100 ms) for smooth, transparent level matching.

Creative Uses

Tape Warmth on a Mix Bus

Select Magnetic, set Intensity to 20–30%, and enable Autogain. This adds subtle tape-style glue and warmth to your mix bus without changing the balance. The hysteresis modeling gently tames transients while the head bump adds low-end weight.

Tube Vocal Enhancement

Insert on a vocal track, select Tube, and dial Intensity to 40–60%. The asymmetric clipping adds rich harmonics and a natural upper-mid presence boost that helps vocals sit forward in a mix.

Drum Bus Punch

Use Transformer on a drum bus at 30–50% intensity. The low-frequency bump at 60 Hz adds kick drum weight, while the soft limiting controls peaks. This is the classic “console” sound that glues drums together.

Parallel Distortion

Set up O-AnalogSaturation on a parallel send, select Diode, and push Intensity to 80–100%. Blend the distorted signal back in with the original using your DAW’s send level. This adds aggressive edge and density without destroying the original dynamics.

Guitar Re-Amping

Try Tube or Diode on clean guitar recordings. At high Intensity settings with HIGH quality, you get amp-like saturation with the ability to switch between characters after recording.

Troubleshooting

Plugin Not Appearing in DAW

• Rescan your plugin directories in your DAW’s preferences
• Verify the plugin is installed at the correct path (see Installation Paths above)
• On macOS, check that Gatekeeper hasn’t blocked the plugin (System Settings → Security & Privacy)
• Restart your DAW after installation

No Audible Effect

• Check that Intensity is above 0%
• Verify audio is passing through your track (check DAW meters)
• Try switching between models to confirm the plugin is processing

High CPU Usage

• Switch the Quality setting from HIGH to MID or LOW
• HIGH quality uses 4x oversampling, which requires significantly more CPU
• Use LOW quality for tracking and live performance

Clicking or Artifacts When Switching Models

• Brief clicks when switching models mid-playback are normal as the DSP algorithm changes
• For click-free transitions, switch models during silence or while the track is stopped

License Activation Issues

• Check your internet connection
• Verify the license key format is correct: OUA-XXXX-XXXX-XXXX
• Ensure you haven’t exceeded the 3-machine activation limit
• Contact [email protected] if problems persist