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About Mono ↔ Stereo Converter
The Mono to Stereo Spatializer & Pseudo-Stereo Expander transforms flat single-channel mono voice and instrument recordings into rich pseudo-stereo audio using Haas psychoacoustic delay, complementary comb filtering, and binaural stereo widening.
How to Use Mono ↔ Stereo Converter
Step 1
Upload a mono audio file.
Step 2
Select a spatialization algorithm (e.g. Haas Delay or Comb Filter).
Step 3
Adjust the stereo width slider and check the Phase Correlation meter ($+1.0$ is ideal).
Step 4
Click "Export Stereo Audio".
Practical Use Cases for Mono ↔ Stereo Converter
Converting Vintage Mono Recordings into Immersive Headphone Stereo
Expand vintage mono vinyl recordings and old podcast tracks across the stereo field to eliminate centered ear fatigue on modern headphones.
Stereo Widening for Mono Acoustic Guitars and Synths
Apply subtle 15ms Haas micro-delays to mono synth leads and acoustic guitars to widen them across the stereo mix bus.
Input & Output Examples
Spatializing Mono Voice Recording with Haas Delay
Audio: `mono_vocals.wav` (1-Channel), Effect: `Haas Delay (18ms)`, Width: `120%`
Audio: `stereo_vocals.wav` (2-Channel Stereo) with wide spatial separation and mono-compatible phase
Key Features & Performance
- ✓Spatial Algorithms: Dual Mono (Centering), Haas Psychoacoustic Delay (1ms to 35ms), Complementary EQ Comb Filtering, Stereo Chorus.
- ✓Stereo Width control: 0% (Pure Mono) to 200% (Ultra-Wide Spatial Field).
- ✓Phase Correlation Meter: checks mono compatibility to ensure zero phase cancellation when summed to mono.
- ✓100% Client-Side Web Audio API processing.
- ✓1-Click Download stereo audio.
Key Terminology & Definitions
Haas Effect (Precedence Effect)
A psychoacoustic phenomenon where introducing a 10ms–30ms delay to one stereo ear creates a perceived spatial widening without distinct echo.
Phase Correlation (+1 to -1)
A metric measuring the phase relationship between left and right channels; $+1.0$ means perfect mono compatibility, $<0$ warns of phase cancellation.