Running on your device · 0 bytes uploaded Test your speakers, left and right Three tones — left only, right only, both — synthesized in this tab. You are the detector: where each tone comes from tells you whether your channels are wired correctly. idle — no audio is playingPlay the three tones Set a comfortable volume BEFORE playing — start low. The tone is a pure 440 Hz sine at a moderate level, but headphone levels depend entirely on your output volume. 1. 1 . Left only440 Hz · 1.5 s Sound from the LEFT speaker or earcup only. If it comes from the right, your channels are swapped; from both, the stream is being downmixed. 2. 2 . Right only440 Hz · 1.5 s Sound from the RIGHT only — the mirror of step one. 3. 3 . Both (center)440 Hz · 1.5 s Equally from both sides, imaging in the middle. One side silent here (after passing its own step) means a dead channel or a loose connection. - Tones are synthesized in this tab by the Web Audio API — no audio file is downloaded, nothing is recorded, and stopping the test closes the AudioContext entirely. - This is a listening test: you are the detector. A swapped result on one output (TV via HDMI) and a correct one on another (headphones) is an output-configuration fact, not a browser one. - Some setups intentionally downmix to mono (accessibility settings, single-speaker devices, some Bluetooth modes) — then every step sounds centered and neither channel is 'broken'. - This browser does not implement setSinkId, so the test plays through the system default output — switch devices at the OS level if you need to. Nothing in yet Paste, drop, or type to begin. Everything stays on this device. set a comfortable volume first, then press play Next door in Device - Microphone test (/device/microphone) - Webcam test (/device/webcam) All device tools (/device) Canonical HTML: https://nutter.tools/device/speakers Markdown version: https://nutter.tools/device/speakers/index.md Plain-text version: https://nutter.tools/device/speakers/index.txt Agent index: https://nutter.tools/llms.txt