Signal processor for providing variable acoustic effect

Abstract

A musical tone signal processor is included of a computation unit, a register, a controller and an interpolator, and imparts a variable acoustic effect to a musical tone signal. The computation unit repeatedly executes a cycle of computation steps applied to the musical tone signal, using a plurality of parameters so as to realize a desired acoustic effect. The register stores values of the respective parameters which are used individually in corresponding computation steps. The controller operates when a variation is requested in the acoustic effect for designating at least one registered parameter attributive to the requested variation so as to rewrite an old value of the designated parameter to a new value. The interpolator is responsive to the execution of the computation steps each cycle during a transient period of the variation for feeding synchronously to the computation unit an intermediate value of the designated parameter, which is interpolated progressively from the old value to the new value, to thereby ensure the smooth variation in the acoustic effect. The interpolator has a multiple of interpolation channels. A multiple of concurrently designated parameters can be assigned freely to the respective interpolation channels so as to carry out parallel interpolation of the designated parameters.