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Safe by Design

Echo & Feedback Loop Detector

Measures how much sound from your speakers is coupling back into your microphone — the exact condition that causes audible feedback — using a deliberately brief, quiet, volume-capped test tone. This is built to measure the risk safely, never to induce a real feedback squeal to find out.

Status

Click Run Safe Test. It plays a brief, quiet tone through your speakers — nothing loud, nothing sustained.

Result

Coupling Level

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Speaker-to-Mic Coupling
  • Verdict:—

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How to Interpret Your Results

What your coupling number actually means

The figure this tool reports is coupling, in decibels — how much your captured mic level rose while a brief, quiet test tone played through your speakers, compared to your room's silent baseline. It is a direct, measured proxy for how exposed your setup is to real feedback, not an estimate.

Under 3dBNo significant coupling. Your microphone is essentially not picking up your own speaker output — low feedback risk as currently positioned.
3–10dBMild coupling. Some sound is making the round trip from speaker to mic, though unlikely to cause audible feedback at normal volumes.
Over 10dBStrong coupling — a real feedback risk. This is the exact condition that produces audible squeal, especially as speaker volume increases.

Coupling depends heavily on physical position, not just hardware — the same speakers and mic can score very differently just by being angled or spaced differently, which is worth testing directly rather than assuming from the equipment alone.

Benchmark Reference

Coupling Bands at a Glance

GradeCouplingPractical risk
Clear< 3 dBSafe to raise speaker volume without introducing feedback risk.
Mild3–10 dBFine at normal volumes; risk grows if you turn speakers up significantly.
Strong> 10 dBReal feedback risk now — reposition before a live call or stream.

These bands are this tool's own measured thresholds, not an industry standard — they describe what your specific setup is doing right now.

Step-by-Step

How to Run the Test

  1. Click "Run Safe Test" and allow microphone access if prompted.
  2. Stay quiet for about a second while it measures your room's baseline level with nothing playing.
  3. Let the brief tone play — it is deliberately quiet, short, and gently ramped, never held at a level that risks real feedback.
  4. Read your coupling result, then reposition your speakers or mic and run it again to compare.

Notes

Why this test is deliberately quiet

Real acoustic feedback is a runaway, self-reinforcing loop — sound leaves your speaker, gets picked up by your mic, gets sent back out louder, and repeats. Actually inducing that loop to test for it risks a genuinely loud, unpleasant, potentially harmful result. This measures the same underlying condition — how much speaker output reaches your mic — with a tone kept deliberately quiet, brief, and gently ramped, so you get the answer without the risk.

Common Issues

Troubleshooting & Fixes

HeadphonesEliminates the speaker-to-mic path entirely — the single most reliable fix if feedback or echo is a recurring problem on calls.
Increase distance and angleMoving your speakers further from your mic, or angling them away from it, directly reduces how much sound reaches the capsule.
Lower speaker volumeDirectly reduces the amount of sound available to couple back in, at the cost of your own listening volume.
Microphone access blockedClick the camera/mic icon in your browser's address bar to confirm this site is allowed, or check your OS's microphone privacy settings if the browser already shows it as granted.
Result seems inconsistent between runsCoupling is sensitive to exact positioning — even small movements of a laptop lid or speaker between tests can shift the reading. Keep your setup still for a fair comparison.

Common Questions

Frequently Asked Questions

Is it safe to run this test?
Yes — the test tone is deliberately quiet, brief, volume-capped, and gently ramped rather than held at a level that could build into real audible feedback. This measures coupling risk safely instead of triggering an actual feedback squeal to find out.
What is audio coupling?
It is how much sound from your speakers physically reaches your microphone and gets picked back up. Strong coupling is the underlying condition that causes audible feedback — measuring it safely tells you the same thing a real feedback event would, without the unpleasant squeal.
How do I fix feedback or echo on a call?
Switching to headphones eliminates the speaker-to-mic path entirely and is the most reliable fix. If headphones are not an option, increasing the physical distance and angle between your speakers and microphone, or lowering speaker volume, both reduce coupling.
Why not just test with real feedback?
Deliberately inducing feedback to test for it risks a genuinely loud, unpleasant, potentially harmful squeal through your own speakers. Coupling strength is measurable safely at low volume, which gives the same practical answer without that risk.
Does my coupling score depend on my microphone, my speakers, or the room?
All three, but position usually matters more than either piece of hardware alone. The same equipment can score very differently depending on distance, angle, and how much the room itself reflects sound back toward the mic.