The Amplifier-to-Loudspeaker Interface

By Pat Brown

Amplifier-to-loudspeaker Interface – is there anything special about hooking an amplifier to a loudspeaker? Here is a brief look at some parameters that can affect the sonic performance of this important interface.

The Ideal Case

Most analog interconnects in a sound reinforcement system are of the constant-voltage type, meaning that a low impedance output is used to drive a high impedance input. The result is the maximum transfer of the voltage component of the audio signal and minimal current transfer. Such interfaces are not optimized for power transfer, which requires that the circuit impedances be matched. Ironically, the amplifier/loudspeaker interface is of the constant-voltage type.