7

Overload matters

There are no gain controls on RIAA inputs, so the overload margin, or headroom, is of considerable importance. The issue can get a bit involved, as the frequency-dependant gain is further complicated by a heavy frequency-dependant load in the shape of the feedback network. This heavy loading was a major cause of distortion and headroom-limitation in conventional RIAA stages that had emitter-follower outputs with highly asymmetrical drive capabilities, and for some reason it took the industry a very long time to wake up to this. Once more the 5532 op-amp solved that problem.

There are also interesting limitations to the levels which stylusin-vinyl technology can generate. This chapter tries to sort out the issues involved in maximising ...

Get Self on Audio, 2nd Edition now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.