调整您的音频设备 – 低音炮测试 [10 ~ 14 Hz, 15 ~ 19 Hz, 20 ~ 24 Hz, 25 ~ 29 Hz]

Here are four files useful for tuning audio systems 和 低音炮 test. Some frequencies may not be reproduced properly by audio system, but these frequencies while not subsonic, may cause damages to your system if the volume setting is to high。

Track 1 – 10 ~ 14 Hz :

Track 2 – 15 ~ 19 Hz :

Track 3 – 20 ~ 24 Hz :

Track 4 – 25 ~ 29 Hz :

Enjoy!