https://worldradiohistory.com/Archive-All-Audio/Archive-DB-Magazine/70s/DB-1978-01.pdf#page=33^^^
Programmable digital filtering and multiplexing tech-
niques suggest the possibility of independent decoding of
substantially every Fourier (frequency) component of
every directional signal in a coded surround program.
(out of date CD-4 info - only the "...frequency range slightly wider..." is accurate when comparing Matrix encoded LPs and CD-4 LPs)
Kirk Bayne
Programmable digital filtering and multiplexing tech-
niques suggest the possibility of independent decoding of
substantially every Fourier (frequency) component of
every directional signal in a coded surround program.
(out of date CD-4 info - only the "...frequency range slightly wider..." is accurate when comparing Matrix encoded LPs and CD-4 LPs)
Kirk Bayne