Do you think you need a subwoofer?

Dear Scott: Btw, I choose ( too ) 1st order filter for the high-pass on my system. This high-pass filter is inside of my 20.6s. It work for me.

+++++ " So, how to find the proper balance????? " +++++

I think there are no rules here other than: test, test and more tests. Now, why don't contact with the designer/builder of your subs/speakers?

The " spot on " integration of the subwoofers is not an easy task, I take more than six months to do it and today ( time to time ) I still do little adjustements.
I know that this hard work sometimes is very frustating but I can asure you that is worthwhile. Good luck!!

Regards and enjoy the music.
Raul.

yes most people need subwoofer. ironically it should be removed from the system unlees you can truly identify that your source has low frequency information that requires it. your crossover can act as low pass filter. this takes the strain of your main amp and main woofer.it provides an improvement like you will not beleive.

Skushino - Dave Whiner's ModeCalc shows that I have 2 room modes at 70Hz, 3 at 141Hz, 2 at 211Hz, 3 at 282Hz, and 2 at 353Hz.

Running the IM-Bens w/o the subs is no real problem except when a sustained note(s) hit that 70Hz fundamental mode and it's harmonics(?) 211/282/353. Especially the 282Hz notes, seems like there is a 6+dB jump in output with distortion. Noticable, annoying because everything else is so pure and clean, but not ehough to destroy the music.

So far, I've found that lower Marimba/Xylophone/Vibraphone keys really overload the room because of their sustained resonance and decay. Cello can, but i haven't found any works that have hit that long note yet.

I've been looking at pro sound crossovers(Rane) or even some of the digital crossovers(Behringer, etc.) this last week.

But, the IM-Ben's are designed to run fullrange without any crossover at all on the 6.5" Fostex FE-168 Sigma drivers. The only components used (I think) is an adjustable 12dB/octave high-pass filter for the Fostex T-900A supertweeter >16kHz.

I'm a little leery of introducing any X-O into the mix even though all the room modes fall in teh IM-Bens range.

As for the subs, my inital experiments with both subs added into the mix have been pretty bad. I don't have a dedcated sub amp(s) yet, so I've been trying to use some solid state integrated amps/receiver that I have lying around. One's a Audio Refinement Complete(50wpc) and the other is a Harmon Kardon AVR 20 II (60 wpc).

Needless to say, it sucks - flabby, mushy, unrecognizable bass. The other problem is that the Paradigm X-30 sub x-over that I have is outputting noticable distortion/breakup.

Currently, I have the Bailey's in between the IM-Bens(10 ft. apart) facing directly forward. Terry Cain suggested starting with this position because it provides the most bass energy.But, the subs do seriously the room even at low volume - wall panels start to buzz/rattle and there is some extremely low frequency energy being generated.

I need to try positioning the subs at various angles inwards, then outwards to see whether that reduces some interactions. After that, I'll move them outside the main speakers at various angles to see how that works.

Unfortuantely, I cannot locate the subs in the corners because the living room side that the speakers are on is open and overlooks my dining room below. The rear wall is 5 feet behind the railing.

As Raul has pointed out, dialing the sub/mains intergration in perfectly could take months.

Raul -

***Btw, I choose ( too ) 1st order filter for the high-pass on my system. This high-pass filter is inside of my 20.6s. It work for me.***

I will first try placing caps before my amp inputs, for easy changes. I like the idea of permanently locating the filter inside the amp.

***I think there are no rules here other than: test, test and more tests***

My satellites go to ~80Hz. My concern is that a 1st order crossover accomplishes too little for my goals:

1) minimize overlap between sub and sats (only 6dB down at 40Hz and 12dB down at 20Hz!!!)
2) eliminate LF signal from amp, for less distortion

I will test, test, and test. How did you deal with the overlap?

scott

Darkmoebius - Like you, I am on the steep part of the learning curve. Here is an article about sub integration I found interesting:

Getting the bass right

Unlike Terry, the author advocates many reasons for corner placement of subs, to cancel nodes. In any case, you might enjoy the article. Let me know your results if you try placing the subs outside your mains.

scott