The desire for broad dispersion is the main reason most home
speakers are two-way designs (with separate woofer and tweeter)
or three-way designs (with separate woofer, midrange, and
tweeter). By switching to a smaller driver above a certain
frequency, a speaker can maintain broader dispersion at high
frequencies and more consistent dispersion from the midrange
through the treble. To demonstrate what a two-way design does
for dispersion, I measured the frequency response of two
speakers at horizontal positions from -90° to +90° in 15°
increments. The first speaker is the Wharfedale DX-1 Satellite,
a compact model with a 3-inch woofer and a 0.75-inch tweeter.
The second speaker is an experimental model I made using a
4-inch, more-or-less full-range Dayton Audio driver. (You can
see both speakers pictured in Figure 1.) Figure 2 is a polar
plot that shows the dispersion of the DX-1 satellite at five
frequencies, from 1 to 8 kHz. The dispersion is broad — in fact,
almost the same — at all frequencies. Figure 3 sh