What does a complete headphone test cover?
A complete headphone test checks three things: that each earcup plays its own channel, that bass is present and clean, and that high frequencies extend as far as your ears do. Those three checks catch nearly every common headphone fault, from a broken cable to a blown driver to one earbud quietly dying.
The order above is deliberate. Channel problems are the most common and the fastest to find, bass reveals physical driver damage, and the high-frequency sweep separates equipment limits from the limits of your own hearing. The whole run takes about two minutes.
How do you tell a broken headphone from a bad connection?
Wiggle the plug or re-pair Bluetooth while a center tone plays. Sound that crackles, cuts, or jumps between sides as you move the connector points at the cable or jack, not the drivers. A wired connection fault gets worse at specific plug angles; failing drivers do not care how the cable sits.
If one side stays silent no matter how the plug sits, swap the headphones to another device before blaming them. The same silent side on two devices means the headphones; a side that comes back on another device means the first device's jack, Bluetooth stack, or balance setting.
What does healthy bass sound like in the test?
Healthy bass is a clean, steady hum that gets easier to hear as you climb from 20 Hz toward 100 Hz. Good over-ear headphones produce something audible at 30-40 Hz; most earbuds join in confidently by 50-60 Hz. What you never want to hear is buzzing, crackling, or a papery rattle riding on top of the tone: that texture is the signature of a damaged or overdriven driver.
Judge bass at moderate volume. Drivers pushed to maximum with a pure low tone distort even when healthy, which turns the test into a false alarm. If a tone rattles at moderate volume, re-run it a few hertz higher and lower; physical damage rattles across a band, while a one-frequency buzz is often just resonance of something near you.
What does the high-frequency limit actually measure?
It measures whichever runs out first: your equipment or your ears. Most headphones genuinely reproduce 18-20 kHz, so on decent gear the limit you find is usually your own hearing, and that is normal. Adults commonly top out between 14 and 17 kHz, and the limit drifts down gradually with age regardless of how good the headphones are.
The test becomes an equipment check when you compare devices. If you hear 17 kHz on one pair of headphones but nothing above 14 kHz on another at the same volume, the second pair is rolling off early. Keep the comparison honest by fixing the volume and taking a short break between runs; tired ears fake bad results.
When is it time to repair or replace?
Replace when a driver rattles at moderate volume, one side has died on multiple devices, or the balance is audibly lopsided in the stereo test. Those faults live in the drivers themselves, and outside premium models with replaceable parts, driver repair costs more than most headphones.
Repair or work around it when the fault tracks the cable: detachable-cable headphones fix for the price of a cord, and Bluetooth earbuds that fail only in one pairing often just need the pairing rebuilt. Run the full test again after any fix; a clean pass on all three sections is the definition of working headphones.