JBL WEM-1 50-Watt Wireless Amplifier and Expansion Module

Provides a separate transmitter and 50 watt amplifier to wirelessly transmit sound up to 70 feet, thus making any loudspeaker wireless.
Useful to transmit sound to rear speakers in a surround sound system in a wireless setup.
Both transmitter and receiver require power.
Transmitter connects to source with either speaker level or line level inputs.
Includes an equaliser with setting for several speaker models.
Includes a remote control for volume setting.
Allows selection between 4 channels in case of interference on a given channel.

Amazon Review Summary (as at March 2010):

9 reviews with a 4.44/5 rating (4 reviewers giving 5 stars and 5 reviewers giving 4 stars)

Some key points from the Amazon reviews:

Minimal interference in a house with a wireless computer network as well as cordless and cellular phones.
Easy plug and play setup.
Works well as a wireless setup with great sound but you can not expect the same sound quality as a wired setup.
People were successful at powering speakers in other rooms.

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