brent@itm.UUCP (08/26/83)
At the 72nd Audio Engineering Convention last fall in Anaheim,
a paper was presented by Wieslaw R. Woszczyk from McGill University,
Montreal, Canada. (AES preprint #1949) On Bessel Filters as
Loudspeaker Crossovers. The author compared characteristics
of 2nd order Butterworth and 4th order Bessel filters. 4th
order Bessel has sharper crossover and much better (i.e. flat)
phase response. The author constructed a four-way system and
aligned the drivers for optimum impulse response. The result
was a system that was flat in the amplitude and phase domains.
(something like +- 4 db 100-16k and +- 20 degrees phase)
Unfortunately I was unable to make it to that convention
to hear these speakers. (Did anyone out there hear them ?)
But for years, the best studio engineer here in Atlanta has
been custom building studio monitors using Bessel crossovers,
and these are some of the best speakers I have ever heard.
Does anyone else out there have experience with Bessel crossovers?
I think this is the most promising type crossover I know of for
applications where first order Butterworth may be inappropriate.
Brent Laminack (msdc!itm!brent)