Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!uwm.edu!csd4.csd.uwm.edu!info-high-audio-request
From: cs004017@cs.brown.edu (Steve Liebling)
Newsgroups: rec.audio.high-end
Subject: Subwoofer Building
Message-ID: <10976@uwm.edu>
Date: 12 Apr 91 12:39:27 GMT
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Approved: tjk@csd4.csd.uwm.edu
Originator: tjk@csd4.csd.uwm.edu


I am considering building a subwoofer and I have a few questions:

1)  Has anyone had experience with Parts Express? Are their drivers and crossover decent? How are their prices?

2) I read about using a tube for a subwoofer, but how do you set-up the woofer in a room?  Does it go with the woofer firing downward using short stands on which to rest the tube? Do you lie the tube on its side and have the woofer fire sidewides?  How about suspending the tube upright using string from a ceiling?  It seems that this method might better isolate the speaker from the room acoustically but might not be good for resonances. (I don't mean to be pretentious as to understanding all this, I'm just






 putting forth some possibly imaginative hypothesis).

3)  What type of material might be good for an enclosure (if I opt for the non-tube type)?  Plywood?  How thick?

4)  What about amplification? I mean, the most efficient use of the subwoofer would be to amplifiy only the low end, but this entails, having a crossover before the amplifier stage, right?  How would this be possible?

5)  What in the world is a double voice-coil driver?  Simply an electrodynamic transducer with two voice coils suspended in a cylindrical magnet hooked to a cone? Why two, and not just one bigger one?

6) If I use the same amp for my speakers (Boston Acoustics A60's) as for my subwoofer, then do I need a dedicated attenuator for the subwoofer to match the efficiency of my speakers? If so, would it go after the crossover or before?

Thanks in advance,
Steve
cs004017@cs.brown.edu