The MPA4609 is one of the lowest noise, fixed gain, 5V single-supply, differential amplifiers available for amplification of low-level signals in a variety of system applications. The chip has two sets of four differential input, low-noise amplifiers that are routed to four output stages. Two standard logic input select lines control which set of four input preamps are active. For applications such as tape recorders, four heads in forward and four heads in reverse can be selected at one time.