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Originally Posted by
davide128 
Thx for this detailed response. I'm still confused as to
how this will make the 5.1 sound better?
It improves the sound by having the subwoofer reproduce the very low frequencies (below the CF you set) which are difficult, or impossible, for the smaller speakers to handle. It is all about improving the sound of the bass, and in turn, allowing smaller speakers to then produce better mids and highs, because they are not "choking" trying to produce bass frequencies they just can not do.
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What configuration do you recommend and why.
a) Should I set my ML to "large" and
b) Sub to "yes/on" and
c) Surrounds to "small"?
According to the ML web site: Preface speakers are able to produce from 35Hz to 20,000 Hz at ±3dB.
a) That is a very respectable front speaker capability, so you have two choices (both will work):
1) Set the MLs (your Front L/R) to large, OR
2) Set the MLs to small and the crossover to 40Hz. (I.e. just a bit above the MLs specified low end of 35 Hz)
b)
Yes, set the sub to YES or ON
c)
Yes, either the PC800s or 1000s would best be set to small.
From the Def Tech web site, the low frequency 3db point for 800s/1000s are 57Hz and 42Hz respectively. Therefore,
for 800s I would set CF to 80Hz, and
for 1000s I would set the CF to 60 Hz.
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By setting CF to 60 on my ML will any sound 60 or below will go to SUB and anything above 60 will go to Mains?
Yes, but only for the Front Left and Front Right audio signals. By golly I think you got it!
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If I set my surrounds to 100 then any frequency above 100 will play on my surrounds?
Yes, and the SUB will play any frequencies from the surround left & right audio signals below 100 Hz. The sub will also play the low freqs (below 60Hz) from your mains as you indicated above--and do it at the same time, with style and class

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If I set both mains and surrounds to 80 then both set of speakers will produce the sound?.
Yes, both sets will produce sounds above 80 Hz from their respective audio signals, and the SUB will produce all frequencies below 80Hz!Quote:
. . . what's the order that the AVR (use) to send out these frequencies? does it try the mains first and then the surrounds. sorry just a bit confused : )
No, keep in mind
in a 5.1 set-up each channel (FL, C, FR, SR and SL) are getting separate and different audio signals. Just like the left and right channels in your Dad's old fashioned "STEREO" set-up gets a separate, and distinct audio signal (thats the whole point of either stereo or 5.1, isn't it).
You also asked about a "prefered setup". That is a more difficult question to answer, it varies and normally involves some trial and error.
Here is a quick process to help you find out what works in your room, with your equipment, and your speakers.
1) Read up on how to place speakers in a room, and follow these guidlines as well as your room will allow.
2) If your AVR has an "Auto" set-up feature (MCACC, YPAO or Audessy) using a microphone--USE THIS FEATURE!
3) Take the time to listen to some CDs and DVDs with what the AVR has calculated. You need this reference to see if any changes you make later on improve or worsen the sound.
4) Find and note the low frequency capability of your speakers and then check that the "Auto" set-up derived values seem to make sense.
5) Perform "manual" set-up experiments (the how is in your AVR's Owners Manual) to see if you can/should improve the results of the Auto set-up procedure.
I have used Yamaha's YPAO and it was OK, but needed some adjustments.
I have also used Denon's Audessy Multi-Point and I could not improve on it.
Making any sense yet?
XEagleDriver