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Phase Test
Compare in-phase and inverted stereo — what to listen for explained.
440 Hz test tone — compare in-phase vs 180° inverted right channel.
Ready
Signal
In-phase
Both channels carry the same polarity. Sound is full and mono-compatible — normal stereo playback.
Out-of-phase
Right channel is inverted. On spaced speakers, bass may cancel in the center (thin sound). Useful for checking wiring polarity.
No microphone needed
This test only plays generated audio — no input required.
How to use
Adjust settings
Use sliders and controls to set frequency, volume, and waveform. Changes apply in real time.
Export or share
Download a WAV file or copy a share link. All processing stays on your device.
Frequently asked questions
Do I need a microphone?
No. This test plays generated tones only.