FreeImgFixSound Lab

Perfect Audio Testing for Speakers & Headphones

Check L/R balance, phase polarity, frequency response, and microphone function.
Instant web-based tool, 100% secure with local browser processing.

Start the Sound Lab

Please check your volume before proceeding, as sudden sounds may occur.
Click below to initialize the audio engine.

LIVE MONITOR Standby

Advanced Diagnostics

Stereo Imaging

Verify sound is centered between speakers.

Phase Polarity

Check for correct wiring (In vs Out of Phase).

Frequency Sweep

Plays 20Hz (Sub-Bass) up to 20kHz (Treble).

Noise Generator

White/Pink Noise for speaker calibration.

Microphone Function Test

If the monitor graph reacts to your voice, your microphone is working. (Headphone monitoring is disabled to prevent feedback.)

Press the button and allow microphone permission to proceed.

FreeImgFix Sound Lab Usage Guide

🛡️ Secure Local Processing

All audio signals are generated using the browser's Web Audio API without transmitting data to an external server. This ensures data privacy and zero bandwidth consumption.

🎧 Headphone Diagnosis

Instantly check for L/R balance issues, cable breaks, or incorrect wiring (Phase Polarity) on new or existing audio equipment.

Frequency Sweep: Use this test to determine the full audible range (bass, mids, treble) your equipment can reproduce cleanly.

Pink Noise: Ideal for speaker break-in (burn-in) or balancing room acoustics, as it has equal energy across every octave band.