Horn size dimensions affect sound?

[kringle77]

How does the physical size of a horn lense affect the sound of a pa speaker? Assuming that you are using the same driver, say a selenium dti220, and two lenses have the same 90 degree verticle 60 degree horizontal dispersion, how with the physical size of a lense affect the sound?

Im looking into having lds build me a pair of tops bases around an eminence kapplite 3015 and selenium dti220 horn.

[zac2944]

Hopefully Bill F. will chime in and give us the straight story, but I believe that when properly designed a larger horn will allow the driver to have more output down low.

[TimmyP]

The larger the horn, the more apt it is to retain its claimed dispersion as the frequency decreases. Horns that are too small suffer from "pattern flip" - the dispersion reverses, causing a loss of sound near the crossover frequency on the horizontal extremes, and loss of pattern control (and cancellation near the crossover frequency) in the vertical.

[kringle77]

Thanks for the information! Im having some pa tops built and they will be crossed over at around 1.6khz. So, maybe a 6x12 lense would be big enough.

[TimmyP]

When you custom build you most always get speakers that:

Are as good as store bought IF the builder knows how to get the crossover right. Not likely.

Have no resale value.

[M0ses]

Bigger speakers have to move less to make the same db, so there's less distortion (because distortion = too much movement).

That's one of many factors, but it's the one I understand the best.