sound rotator

elektor electronics october 1985 sound Audio signals produced by electrophonic instruments, such as electric pianos, organs, and synthesizers, often sound rather artificial and thin, lacking the natural colour of acoustic instruments. Early in electronic organ development, it was realized that a mechanically rotating speaker system (sometimes known as a Lesley speaker system) partially overcame this limitation by providing phase shifts that produce interference, both constructive and destructive, at a number of frequencies in the audio spectrum, which gives vitality and interest to the resulting sound. When two speakers rotate around one another, there exist constantly varying time delays - and therefore phase shifts - in the paths the sound takes to travel from the loudspeakers to the listener. A similar effect can be produced electronically by the use of a delay line with varying time delay. by T S Norris Et M M Bhalsod A charge-coupled device consists of an array of MOS cap...