Technically, that should be the case. I practical terms, it is not. Horns just sound different than direct radiators. The dispersion patterns are very different between them for starters. Horns also can in theory produce lower distrotion by virture of the fact that the diaphrams don't have to move as much to reproduce the same sound level. Horns can also handle sound pressure levels that would shread a direct radiator speaker. Horns have their own set of problems. They can sound colored of not implemented just right.