Sennheiser Electronic Corp, Old Lyme, Conn, offers DirectEarSAS Soundfield Amplification System for classroom amplification. The wireless transmitter and comfortable headset allow freedom of movement. The high-quality condenser microphone and loudspeakers deliver lifelike fidelity and protection from feedback. The Sennheiser DirectEarSAS installs easily and requires very little maintenance. (860) 434-9190, ext 153; www.sennheiserusa.com.