Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site bonnie.UUCP Path: utzoo!watmath!clyde!bonnie!saf From: saf@bonnie.UUCP (Steve Falco) Newsgroups: net.audio Subject: Re: Speaker Sensitivity Message-ID: <601@bonnie.UUCP> Date: Tue, 29-Oct-85 08:58:53 EST Article-I.D.: bonnie.601 Posted: Tue Oct 29 08:58:53 1985 Date-Received: Wed, 30-Oct-85 05:40:27 EST References: <480@uvaee.UUCP> Organization: AT&T Bell Laboratories, Whippany NJ Lines: 26 > Does anyone know how the speaker configuration (vented, sealed, etc.) > affects a woofers sensitivity? Acoustic suspension speakers are known > for being less efficient than bass reflex speakers :-) > Is this because IT IS an acoustic suspension speaker, or is it because > the drivers used are less efficient than drivers used in vented speakers? > > Does anyone know how to decide if a driver will work in a TL or horn? Acoustic suspension is less efficient than bass reflex for a couple of reasons. First, in bass reflex, the sound from the port adds to the volume while in acoustic suspension, that sound never leaves the box. Second, acousic suspension is very springy because the air is trapped. Consequently, it retards cone motion. For horns, you want a driver with a stiff suspension. Not rolled polyfoam! Klipsch uses an old style cloth accordion pleat which is quite stiff (made by Eminence (sp?)). Now here's my question: If you seal the box for acoustic suspension, how do you handle changing barometric pressure - it tends to displace the cone from center... Maybe there should be a valve on the side of the box to allow mountain dwellers to bleed off some of that extra air the factory put in the box. (Guess I'd better put a :-) in to avoid the flamers...) Steve Falco