Nousaine wrote:
"Michael McKelvy" wrote:
"Robert Morein" wrote in message
...
Opinions regarding the use of D'Apolitto for main speakers?
Presumably, it reduces floor and ceiling bounce in the region of
configuration.
Correct.
As I recall that's not the primary function. Rather the performance improvement
that comes as a function of the D-Appolito topology is an improvement in the
pattern of horizontal directivity with the price being a worsening of lobing
vertically.
It seems that a some people have found interesting and balanced results
in builting serial 2.5 ways crossover for these d'Apolitto configurations.
FWIW few MCMs have driver spacing and crossover frequencies that qualify as
D'Appolito (drivers too far apart and crossover frequencies too high.)
The timbre change that occurs with listener height obviously depends upon
the physical layout of the mids and the tweeter.
And the movement of the listeners head.
Some modern designs have a
single mid spaced closely to the tweeter. Other modern designs have
multiple
mids, some a foot or more away from the tweeter.
I find it surprising that so many physical arrangements continue to exist.
One might think that this element of speaker design would converge, but it
hasn't.
Placement of drivers in well thought out speakers relates to the crossover
frequency and the size of the driver. Sound tends to beam when the
wavelength approaches the size of the driver.
As good as the MTM configuration is for stereo listening, it is not good for
a horizontally placed center channel, yet they seem to dominate the market.
A coax or 3 way seems better suited.
Agreed. One of the better center channel topologiesis a vertically aligned
6.5-inch 2 way. There are any number of excellent models of this design at
incredibly reasonable prices.
The reason that horizontally arrayed center channels dominate the market is
simply a function of style and appearance. I call it the industry's Dirty
Little Secret. Many are aware of it but nobody talks about it.I'm not limiting
myself to mainstream companies either. One of the worst center channel speakers
I've seen is a horizontally arrayed expensive init using exotic drive units.