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Path: utzoo!watmath!clyde!bonnie!akgua!gatech!itm!brent
From: brent@itm.UUCP (Brent)
Newsgroups: net.audio
Subject: Re: Speaker building
Message-ID: <244@itm.UUCP>
Date: Sat, 30-Mar-85 07:51:44 EST
Article-I.D.: itm.244
Posted: Sat Mar 30 07:51:44 1985
Date-Received: Mon, 1-Apr-85 04:15:34 EST
References: <2300018@hp-pcd.UUCP> <90@vice.UUCP> <23457@lanl.ARPA> <2520@tekig.UUCP> <510@harvard.ARPA>
Reply-To: brent@itm.UUCP (Brent)
Organization: In Touch - Atlanta, GA
Lines: 25
Summary: 


X
	About 50mm speakers and such... In Thiele-Small speaker design
(woofer-cabinet tuning criteria)  The bass response of a speaker is
determined by it's resonant frequency, the Q-factor of that resonant
peak, and the driver's compliance.  Period.  The diameter of the 
driver doesn't enter into the calculations anywhere.  What you will
find is that the cone excursion for low bass from a small driver will
be huge.  That's how Bose claims to be able to get such bass.  Their
drivers have a very long throw: i.e. they have a lot of linear travel
while remaining fairly linear.

	On the high end, yes, mid-size speakers may well be linear
out to 20kHz, but the problem there is horizontal dispersion.  When
the physical wavelength of the sound is roughly equal to the diameter
of the driver, you start to get "lobing", or "beaming", as the frequency
increases, the sound gets directed into a tighter and tighter beam of
sound (up to a point)

	So the bottom line is yes, much of what the man said is true, but
there's more to the story than that.

 	Happy listening,
-- 
            Brent Laminack  (akgua!itm!brent)