(57) Virtual surround systems enable a spatial representation of audio signals merely
using the front loudspeakers (SL, SR). In this case, the surround channels (C, Ls,
Rs) are fed to the two front channels (L, R), the virtual surround effect being attained
by these surround channels being processed beforehand. In particular in the case of
static objects or objects which are only moving slowly, the quality of the acoustic
reproduction by known virtual surround systems is, however, behind the quality in
the case of a reproduction by a high-grade multi-channel audio system. According to
the invention, it is possible to achieve an improvement in the acoustics by the virtual
surround sources being moved. This can be done with constant periodicity or as a function
of the amplitude of the front channel signals (L, R). If the virtual position of the
surround loudspeakers (SLs, SRs) is specified by filtering of the rear channel signals
(Ls, Rs), then this can be varied in particular by alteration of the filter parameters.
Equally, however, this can be done exclusively or additionally by means of a different
propagation delay, amplification or matrixing of the rear channel signals (Ls, Rs).
|
|
