The OP-09 and 0P-11 provide four matched 741-type operational applifiers in a single 14-pin DIP package. The OP-11 is pin compatible with the LM148, LM348, RM4156, and HA4741 amplifiers. The amplifiers are matched for common-mode rejection ratio and offset voltage with is very important in designing instrumentation amplifiers. In addition, the amplifier is designed to have equal positive-going and negative-going slew rates. This is an important consideration for good audio system performance.