The Energy Star compliant AV-20D and AV-60S are great small format class D amplifiers suitable for most typical AV applications. This compact amplifier is equipped switching power supply circuit inside,  and is PLENUM rated (UL 2043 tested) for the installation into air handling space without external AC adaptor. 

Because of their Energy Star compliance, these amplifiers will go into sleep mode after a period of time. The amplifier will remain in this state until an audio signal is received.

This wake up time period can be a few seconds and may result in loss of paging information at the beginning of the page. As a result, the AV-20D and AV-60S are not suitable for audio paging applications.