This discloses an improved side-scan sonar capable of locating objects on e ocean floor including the strip directly beneath the sonar transmitter and receiver, which in prior arrangements had to be obtained by another pass. The arrangement includes a platform having acoustic transmitters spaced apart a substantial distance on either side of acoustic receivers. The transmitter on the right directs its acoustic output to the left and the transmitter on the left directs its acoustic output to the right for increased shadow forming and enhanced detection by the receiver of objects of height directly beneath the receiver.