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Path: utzoo!linus!cca!decvax!harpo!eagle!alice!rabbit!jj
From: jj@rabbit.UUCP
Newsgroups: net.audio
Subject: High power amps/speaker effeciency(sp)
Message-ID: <1576@rabbit.UUCP>
Date: Thu, 9-Jun-83 11:48:10 EDT
Article-I.D.: rabbit.1576
Posted: Thu Jun  9 11:48:10 1983
Date-Received: Fri, 10-Jun-83 16:11:48 EDT
Organization: Bell Labs, Murray Hill
Lines: 13


I've noticed that most drivers (most woofers actually) that I've used
in speaker systems have an effeciency roughly equivelent to
82-90 dBSPL at 1 watt/1 meter.  

I find the numbers given in some of the previous articles quite low,
i.e. 70dB at 5 watts, even given a large, dead room, sounds at best like
76dBSPL at 5 watts/1 meter.  (You'll be surprised how much energy is stored
in a "dead" room.)  That's about 69-70dB SPL / watt / meter.  That's
a very low conversion efficiency, even for "hi-fi" speakers.

Highly effecient components (for sound reinforcement, not accurate reproduction)
manage 100dB/w/m for cone drivers, and higher for compression horn drivers.