For those who have had the opportunity to compare both in a fairly direct capacity, what are your opinions of the largest multicell Altec horns compared with far smaller contemporary horns like a Ciare PR614 or similar at midfield living room distances of ~10-30 feet?
Neither of these are exactly a waveguide, or at least they are somewhere on a continuum. The curvature does affect the dispersion. You typically have to set aside the idea of horn loading for specific waveguide design allowing size efficiency and dispersion qualities.
This can be a problem when the advertised lower frequency range of a curved horn is specified by the cutoff frequency, since the cutoff frequency is a loading term and doesn't relate to dispersion. The dispersion lower limit is usually further up than for a waveguide which has a more conical profile.
For the same reasons a horn with narrow angles can also have difficulty controlling directivity at lower frequencies for it's size.
This can be a problem when the advertised lower frequency range of a curved horn is specified by the cutoff frequency, since the cutoff frequency is a loading term and doesn't relate to dispersion. The dispersion lower limit is usually further up than for a waveguide which has a more conical profile.
For the same reasons a horn with narrow angles can also have difficulty controlling directivity at lower frequencies for it's size.
Good Q since we didn't have modern CD horns to compare with, though you can compare some factory measured vertical, horizontal, calculated mean polars of several multicells with the Ciare........and some basic info of the horns for those not familiar with such 'beasts'. 😉
