Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site opus.UUCP Path: utzoo!watmath!clyde!floyd!harpo!seismo!hao!cires!nbires!opus!rcd From: rcd@opus.UUCP Newsgroups: net.audio Subject: Speaker "power rating" Message-ID: <263@opus.UUCP> Date: Fri, 23-Mar-84 19:31:15 EST Article-I.D.: opus.263 Posted: Fri Mar 23 19:31:15 1984 Date-Received: Sun, 25-Mar-84 19:29:26 EST References: <1840@tektronix.UUCP> <352@dual.UUCP> <240@opus.UUCP>, <364@dual.UUCP> <186@cubsvax.UUCP> Organization: NBI, Boulder Lines: 59 <> The matter of the AR-11's has digressed quite a bit. I'll buy the idea that the original poster had a genuine problem with the tweeters - fine. Now we've gotten into a different matter - that of having the right correspondence between amp power and speaker capability. Everyone is absolutely right - DON'T use an underpowered amp; it will clip and fry tweeters. BUT there's another problem - it IS possible to use too large an amp and actually overdrive speakers with enough clean signal that you actually burn them out. It takes a whole bunch of power to do this, but it can be done. I was looking at an ad for a reasonably well-known speaker in a recent issue of an audio magazine. The ad made a point of the fact that this speaker has a "power handling capacity" of 400 watts! <> This is first-order BS, and it's one of the stupidest things speaker manufacturers have ever done to us. You don't care how much power the speaker can handle, you care about being able to give it enough power to make the sound as loud as you want it. The goal is accurate sound reproduction, not space-heating. The lower the efficiency of the speaker, the more power it must handle in order to be able to reach the same sound level. No responsible speaker manufacturer should publish power handling capacity without a corresponding efficiency rating. <> It would be most useful to combine the two - give the maximum SPL (in appropriate units under appropriate conditions) that the speaker can produce and the power input to the speaker required to produce it. For those who doubt the argument against "power handling capacity", I submit the following non-proprietary, non-patented Magic Power Capacity Enhancer (8 ohm design). (Sorry about the graphics): o-------------/\/\/\/-------+---/\/\/\/---+ R1 | R2 | o | From amp To speaker | o | | | o---------------------------+-------------+ To double power capacity, R1=4 ohms, R2=8 ohms. To triple power capacity, R1=5.3 ohms, R2=4 ohms. Both resistors should be rated for a s***load of watts. Not only will this simple network increase the power handling capacity of your speakers, it will actually improve the loading characteristics of the amplifier! The effects of varying speaker impedance as a function of frequency are reduced, at the amplifier output terminals, by approximately the same factor as the increase in "power handling capacity." -- {hao,ucbvax,allegra}!nbires!rcd