Question about LsiFx

l80241

I just mounted a pair of LsiFx speakers on the side walls of my new theater room. I mounted the left speaker on the left wall and the right speaker on the right wall (while facing the screen).

So, is it normal to have less sound (volume) coming out of the reat set of drivers than the front set of drivers? It is pretty significant and I actually unscrewed the rear tweeter to make sure it was connected.

The bipole/dipole switch doesn't seem to make any difference in sound either.

Any help appreciated. I searched, but didn't find much on this.

Thanks

l80241

BUMP!!!! Hopefully this is not too ignorant a question for a response. If so my apologies.

Phishman

I have the same question. I understand that the drivers are crossed over at different frequencies, but what about the tweeters? Should one tweeter be signficantly louder than the other?

Thanks,

aaharvel

if you're unsure of the setting and or both the bi/di modes sound the same, leave the speakers on BIpole mode. This way, each side of the lsifx's fire in-phase with each other. In DIpole mode, one side fires out of phase with the other.

Typically, Dipole is recommended for side placement and movies. Bipole is recommended for rear-wall placement for movies/music and side-wall placement for music reproduction only.

fireshoes

Dipole is best used if the FX's are directly to the sides of your seating area. If the speakers are on the side wall but behind the seating area, I would use bipole.

wallstreet

Run a test tone and calibrate with a SPL meter. Otherwise you're just guessing on what was mixed in your source material.

Phishman

Perhaps I'm not being clear with my question. On both speakers, the "inner side" tweeter is signficantly lower in volume that the "outer side" tweeter. I am wondering if this is normal or do I have defective speakers?

Thanks,

Gaara

I noticed this with my Fxs to, except the woofer facing the rear was louder then the one facing the front.

Of course I just took down my Fxs to try some Gallo Due's, and after reading this post I realized that I am a moron, and had the left and right reversed. So if mine were setup properly the forward facing drivers would be louder then the rear...I am not sure why this is though and always thought it was caused by the crossover, like with the center. I would be curious to know the answer as well.

Jared

wallstreet

I don't know although my fx-1000's don't exhibit that behavior.

fireshoes

I don't have mine hooked up at the moment to check either, but if you turn the switch from bipole to dipole (or vice versa) do the rear-firing drivers increase in volume to a more equal level?

T-man

Yes I have the same problem. The rear facing "speakers" are not as loud, or may not even have sound coming out of them, in dipole or bipole. I know exactly hat you are talking about l80241. Even if they are made to be out of phase in dipole, shouldn't there be sound coming out of it?

Marcinko7

I have the same thing with mine. I just figured since the outside speaker banks off the wall they made it louder to compensate.;)

dane_peterson

Now this is not in reference to the LSiFXs, but I have heard of other members switching the surrounds around so that the side with more sound is pointing away from the display. This has apparently aided in creating a more enveloping sound...
With that being said, it sounds like that's what is supposed to happen.

cheddar

Wow is this an old thread without an answer. So here it goes. Polk uses something in its dual driver arrays (like the lsi series) called the cascade tapered array, http://www.polkaudio.com/education/tech_article.php?id=23. Basically it crosses over the midrange woofers at separate frequencies so that they do not interfere with each other across the high/low frequency spectrum.

That means that one side of any lsi speaker (except for the 7) will always sound like it's missing some highs although it's really the upper midrange that's missing on one side and the lower midrange on the other. Now with drivers facing the same direction, this is often unoticeable. I actually had to put my hand on the the drivers to feel the difference through vibration since it sounded like one midrange wasn't producing any sound because it was crossed over so low.

The problem with the lsifx is that both sets of drivers face in opposite directions. So the difference in sound in very appearant from the two sides. Now the interesting thing for me is that dipole speakers are supposed to cancel the sound in a null area in front of the speaker by causing interference across the frequency spectrum (out of phase) that cancels the sound in the null area. It seems to me that the cascade tapered array can only create a null area for the highest frequencies created by the two out of phase tweeters since the midranges don't overlap. I really wonder how effective the speakers are in this regard, but it's not a malfunction in the speaker as it is definitely designed to work this way. If you are concerned that a tweeter is not functioning, just put your ear up to it. You should hear the highest highs from both sides. But from a distance, one side will seem to be lacking in highs because that midrange is the low range driver. If you don't think it's functioning, you can just look at it. It will probably vibrate even more than the other midrange 'cause it's pulling all the low-end duty of the array.