Loudspeaker impedance correction

A loudspeaker looks a simple enough device: a frame, a coil, a magnet, and a cone of paper or of man-made fibre. Put it in a box and you have a sound reproducer. If only it were as simple as that... Designing a closed loud- speaker box (Elektor Elec- tronics, February 1986) explained the fundamen- tals of calculating the di- mensions of a closed box on the basis of the characteristics of the drive unit used. That thus dealt with the acoustics of the system. The present article takes a closer look at the electrical aspects. Before reading any further, note that if the cross-over network is of the active EE 30 May 1986 LOUDSPEAKER IMPEDANCE CORRECTION A loudspeaker presents a complex load to the output amplifier and the cross-over network This load can be measured and any deviation from the nominal impedance corrected In this manner a multi-way loudspeaker system with a passive cross-over network can be made to function optimally. la DISPLAY SCALE f107-2-5 50ILIN1 2 5 1011251 dB d...