For example, the 84-dB SPL calibration level that you used with the Avia test DVD is termed "quite loud" by most listeners. THX's certification program for movie theaters typically sets cinema ...

Measuring equipment such as SPL (Sound Pressure Level) decibel meters may seem daunting, but this article by [Shawon M. Shahryiar] shows that making your own need only have two essential ingredient… ...