Audible Dynamic Range Test

Background

Dynamic range represents the ratio between the loudest signal you can hear and the quietest. Dynamic range is expressed in terms of decibels (dB). Being a ratio, the decibel has no units; everything is relative. Since it is relative, it must be relative to some reference point that has to be defined. Our reference point here is the loudest level you can comfortably bear for one second. This test helps you benchmark the dynamic range of your sound system.

The file

The file first starts with a reference point: a slightly compressed pink noise which tops out at 16-bit full scale (0dbFS). This noise plays for 1 second. Adjust the level of your system so that this noise plays loudly, without being uncomfortably loud.

Dynamic Check + Voice Over

Right after the noise, a voice plays back at a specified level. Noise references and voiceovers alternate with each other, with the voice being played at decreasing levels.

Usage

Play the file until you can't hear the voiceover anymore. The dynamic range of your system is roughly given by the level the voice message was playing at when it was still (barely) audible. The limiting factor here will be the environmental noise in your listening room. The ambient noise level in a quiet room is generally considered to be 40dBA, and 90dBA the upper limit for a loud yet "comfortable" playback level. The difference between those two figures is 50dB. This means that - in most cases - you won't hear the voice once it drops below 50dBFS. For those used to extremely loud levels, or very quiet rooms, our test goes down to 78dB below full scale.

Interestingly, much emphasis is put on 24-bit audio recordings nowadays, with a dynamic range exceeding 140dB. Our example is only 16-bit, with a maximum dynamic range of 96dB, yet that should be plenty. Judge for yourself.

Links

• About Decibels
• Table of Sound Pressure Levels