Tweeter Test Tones
Play clean high-frequency sine tones from 2 kHz to 20 kHz — stepped, continuous, or as a slow sweep — and hard-pan them to the Left tweeter, Right tweeter, or both, so you can hear whether your treble drivers are working and matched.
⚠ Safe volume: high tones can be loud and ear-fatiguing without sounding loud — start quiet and never crank an inaudible tone. Honest limits: this is a tone generator, not a measurement — there is no microphone and nothing is recorded. If you can’t hear the top tones it is usually your ears (normal age-related rolloff, or presbycusis) and/or a device that rolls off above ~16 kHz, not necessarily a dead tweeter. To isolate a tweeter, compare Left vs Right at the same frequency: a side that’s silent or much quieter points at that driver/channel; both sides dropping out together points at your hearing or the device.
Test signal
Typical Upper Hearing Limit by Age
These are widely-published typical population averages for healthy ears (the gradual loss of high-frequency hearing with age is called presbycusis; the trend is described in standards such as ISO 7029). They are a rough guide only — individuals vary a lot, and noise exposure, hardware and listening level all shift the number.
So if a 45-year-old stops hearing the 16 kHz tone, that is squarely in the typical range — not evidence of a faulty tweeter.
How It Works
A tweeter is the small driver in a speaker that reproduces the high end of the spectrum — roughly the top two octaves of music, from a few kilohertz up to the limit of hearing. This tool generates a pure sine tone with the Web Audio API’s oscillator and routes it through a stereo panner and a gain stage to your speakers or headphones. In stepped mode it sits on each round frequency (2, 4, 6, 8, 10, 12, 14, 16, 18, 20 kHz) so you can step up and down; in continuous mode a slider sets any frequency in the band; in sweep mode it glides smoothly from 2 kHz to 20 kHz over about twelve seconds so a single listen covers the whole top end. Gain is ramped up and down to avoid clicks, and the default level is deliberately low because steady high tones can fatigue your ears without ever sounding loud.
The channel selector hard-pans the tone fully left, fully right, or centres it on both. That is the key to telling a real fault apart from a limit you simply share on both sides: play, say, 14 kHz on Left, then switch to Right at the same level. A working pair of tweeters should sound essentially the same loudness on each side. If one side is silent or noticeably quieter, the suspect is that tweeter, its crossover, the channel of your amplifier, or the cable — not your ears. If both sides go quiet at the same frequency, the far more likely explanation is your own hearing rolling off, or the device/output rolling off (many phones, laptops and Bluetooth links attenuate everything above ~16 kHz).
Two honest cautions. First, browser audio output is stereo (two channels): we can address Left and Right with a stereo panner, but we cannot reliably drive discrete surround channels (5.1/7.1) from a web page, so this tests the front L/R pair only. Second, “I can’t hear it” is not the same as “the tweeter is dead.” Because this is a generator with no microphone, it cannot measure output level, distortion, or frequency response — for that you need a calibrated measurement microphone and software such as REW, or a real SPL meter. Use these tones to find gross problems and to compare sides, then measure if you need numbers.