1999 for example under operation of the cross talk canceller 40 the outputs arc converted into the sounds which when heard over speakers in a specified position are roughly heard by the left ear only from the left side speaker and sounds which are roughly heard by the right ear only from the right side speaker such sound allocation roughly simulates the situation in which the listener hears the sounds by use of a headphone set the filter 36 mixer scaler 38 and cross talk canceller 40 may all be provided on a single chip as indicated by the dotted line shown in fig1 for example the components included in path 34 and described below may similarly be provided on a single chip the signals sent along path 34 are input to a plurality of filters 42 only one shown which add spectral coloring to the signals to smooth out the signals and approximately match the hrtf filtering the filter 42 receives a mono input and produces a plurality of outputs equal to the number of rear speakers e g two the filters 42 are position dependent as described above for the filters 36 the filter 42 may be the same as the hrtf filters 36 used for the front speakers or some approximation of the hrtf filters preferably the filter 42 does not provide all of the processing included in the hrtf filter 36 to reduce system complexity the filter 42 frequency characteristics are preferably designed to minimize tibral differences or mismatch between the front and rear speakers and help to provide for smooth transitions from the front speakers to the rear.