Headphone Amplifiers

Driving Heavy Loads

This chapter focuses on techniques for driving loads heavier than can be handled by a single 5532 or LM4562 opamp –basically any impedance less than 500 Ω. This is typically a headphone load, the impedance of headphones varying widely from 600 Ω to 16 Ω or less, with sensitivity inversely related so the higher impedance models need more drive voltage. The need to drive impedances below 500 Ω is also likely to arise in very-low-noise designs, so that special measures have to be taken just to drive the next stage. A good example is my Preamp 2012 design for Elektor. [1] It is assumed here that the heavy loads must be driven to the same high standards of noise and distortion that are required ...

Get Small Signal Audio Design, 3rd 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.