ABSTRACT
Audio design has for many years relied on a very small number of op-amp types; the TL072
and the 5532 dominated the audio small-signal scene for many years. The TL072, with its
JFET inputs, was used wherever its negligible input bias currents and low cost were important.
For a long time the 5534/5532 was much more expensive than the TL072, so the latter was
used wherever feasible in an audio system, despite its inferior noise, distortion, and load-
