A method of disassembling a pair of input signals L(t) and R(t) to form subband representations of N output channel signals o1(t), o2(t), . . . , oN(t), wherein t is time. The method includes the steps of generating a subband representation of the
signal L(t) containing a plurality of subband components Lk(t) where k is an integer
ranging from 1 to M; generating a subband representation of the
signal R(t) containing a plurality of subband components Rk(t); and constructing the subband representation for each of the plurality of output channel signals, each of those subband representations containing a plurality of subband components oj,k(t), wherein oj,k(t) represents the kth subband of the jth output channel
signal and is constructed by combining components of the input signals L(t) and R(t) according to an output construction rule: oj,k(t)=f(Lk(t),Rk(t)) for k=1, 2, . . . , M and j=1, 2, . . . , N.