Matrixed quadraphonic crosstalk made localization unstable with head movement

Evidence

There were two categories of quadraphonic systems in use: matrixed and discrete. The encode/decode matrixed systems downmixed four signals into the bandwidth normally used for two channels. In doing this, something has to be compromised and, as a result, all channels did not have equal channel separation from the others. Information that was supposed to be only in one channel would appear in smaller quantities in some or all of the other channels. The result of this “crosstalk” was confusion about where the sound was coming from and an extreme sensitivity to listener position; leaning left, right, forward, or back caused the sound panorama to be biased in that direction. The sweet 212. spot was very small. Spacious classical music was a favorite in demonstrations, but the ambiguity in localization was not always flattering to popular music. — Toole, Floyd E, Sound reproduction- the acoustics and…, 754

Categorization

• DEFINE: Defines the core tradeoff of matrixed vs discrete multichannel: crosstalk leakage degrades separation and stability.