ABSTRACT
This chapter presents an active crossover design which illustrates a good number of the principles and techniques. The design is a generic crossover that can be adapted to a wide range of applications by changing its parameters and its configuration. The crossover frequencies can be changed simply by altering component values, and circuit blocks for equalisation or time delay can be added or removed, with due care to preserve absolute phase, of course. The crossover design is primarily aimed at hi-fi applications rather than sound reinforcement. The crossover has balanced inputs, but in its basic form the outputs are unbalanced, the assumption being that if a balanced interconnection is required, this will be provided at the power amplifier inputs. The chapter examines the possibility of adding balanced output stages. Low-impedance design is used throughout; the circuit impedances are designed to be as low as possible without causing extra distortion by overloading opamp outputs.
