Sennheiser has added the EK IEM G4 Stereo Bodypack Receiver with IE4 Earphones to their evolution line of wireless systems. It has adaptive diversity technology and can be utilised as a wireless RF monitoring system for live stage, theatre, and rehearsal applications when linked with a companion transmitter.

The stereo receiver has 1680 frequencies that may be adjusted in 25 MHz steps, 20 fixed frequency banks with up to 16 suitable preset frequencies, and additional 6 user banks with up to 16 programmable frequencies. The receiver's menu-driven backlit display lists the current frequency, frequency bank, and channel number as well as RF and AF level metres, lock status, battery level, and the current frequency. In order to prevent settings from being unintentionally changed, an auto-lock feature is included.

This receiver also has a multi-level limiter and a switchable high-boost. The limiter is defeatable or may be adjusted from -18 dB to -6 dB in 6 dB steps (off). It is housed in a tough metal inclosure and powered by two 1.5V AA batteries or a Sennheiser BA 2015 rechargeable accupack. The 3.5mm stereo jack connector is used for the earphone output.