Bonnie, this got sent to me by mistake.  May wanna resend: Quoted in its 
entirety just in case.
J.B./2
BG>**B00000000000000 From    : MARC BAMFORD
BG>> I have been following this echo for some time now (yes, all the way
BG>>from Sydney!) with increasing frustration at the car audio vs home
BG>>audio debate (I enjoy both).  In a vain attempt to distract everyone
BG>>with a question,  I was wondering if anyone could help answer the
BG>>following about my home theatre setup.
BG> Glad to see you and New Zealand back with us again. Now just wish we 
ould
BG>get the Hong Kong crowd back in here again. They REALLY were into the high 
e
BG>home stuff! We missed all of you.
BG>>1.  I have a pair of small 2 way vented speakers as my mains in my
BG>>  home set up and a single sealed 12inch sub running via a small
BG>>  dedicated amp from the lowpass output of the Yamaha Pro Logic
BG>>  decoder (VSX1050).  Even though the main speakers are not
BG>>  particularly "bass heavy" do I need to run some sort of high
BG>> pass filter on them to prevent interference from the sub?
BG> No, I don't believe that you will need to bother. The small mains 
robably
BG>have a built in high pass due to the nature of cabinet size, et al. A 
ower
BG>sub frequency crossover Fc could leave a hole in frequency response 
coverage
BG>on that system. Locate the sub at the center front location, which will
BG>minimize the displacement effects since it's coming from the "window on 
he
BG>wall" is a more natural direction for that band of bass.
BG>> 2.  The lowpass output of the decoder has an Fc of 400HZ and there
BG>>   are lots of directional clues coming from the sub - what is the
BG>>   best Fc to use and how do I do this  - at line level (before the
BG>>   amp) or at speaker level?
BG> That Fc does sound much too high... but then you didn't say just what the
BG>response of those main speakers are, and I agree, directional info is 
there.
BG>Subs work best below about 200Hz where the fundamental frequencies made by 
t
BG>source material reproduce as pressure changes in the room and are
BG>nondirectional and diffuse, even throughout the room except where room 
ode
BG>cancellations cause the sound to wink out which needs room treatment to 
cure
BG> My current "main studio monitors(and keyboard gig/personal sound system", 
i
BG>needed)" starts to fade at 120Hz (3db down point and loses about 6dB the 
fir
BG>octave below,that and about 12 more the next octave down, so
BG>I have the 18" woofers of the (2-1-18" Gauss) currently setup at for about 
9
BG>Hz, on a 6dB/octave electronic crossover and running an EV 100 WHAT? per
BG>channel in the studio or in mono mode as a live system though with
BG>---
 * SLMR 2.1a * "We are Windows '95 of Borg, you will be..."......
--- InterEcho 1.19
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