VoIP audio codec comparison

This page allows you to listen to a sample recording (Microsoft Bob from Wikipedia). You can switch between the different codecs and experience the difference in audio quality. Below the table is a spectrum visualization, which shows how higher frequencies are not reproduced by some of the older/lower bitrate codecs.

Codec Sample rate Bandwidth


The spectrum visualizer shows the magnitude of an input signal versus frequency. On the left are the low tones, towards the right the higher frequencies.