A frequency sweep is one of the most useful general diagnostics for headphones and speakers because it moves through a large part of the audible range in a controlled way. Instead of checking only one bass note or one treble tone, a sweep can expose rattling, sudden level drops, strange resonances or distortion that appear only at certain points. On this page you can run a full 20 Hz to 20000 Hz sweep or split the task into low and high sections when you want a more targeted listen.
A smooth sweep does not guarantee perfect frequency response, but it is a good sign that no major faults jump out in casual listening. If the sound suddenly thins out, spikes, rattles or breaks up, note roughly where that happens and compare with more focused pages such as Bass Test or Hearing Test. Unevenness can also come from ear shape, earbud fit or room reflections when using speakers.
Do not raise the volume to chase the quietest part of the sweep. The perceived level changes across the range, and louder sections can become uncomfortable fast. Keep playback conservative and stop immediately if the sweep becomes sharp or fatiguing.
It covers a wide range quickly and can reveal issues that do not show up when you play only a single tone.
Perceived loudness changes across the range, and your device may also have stronger or weaker output at specific frequencies.
Buzzing can point to driver stress, enclosure vibration or nearby objects resonating. Compare with the Bass Test to narrow it down.
No. Use it only as a playback check. The Hearing Test page also includes a clear note that it is not a medical exam.