Problems with LSi9 as center (Please help)

malikarshad

After reading all the mixed opinions about LSiC I decided to buy single LSi9 for a center channel.
So I bought a single LSi9 to be used as a center channel ( BTW the single LSi9 in the Flea Market was listed after I bought it so no offense intended here)
I got the LSi9 yesterday. I swapped out my CSi40 and hooked up Lsi9. I recalibrated the system using AVIA disc.
The CSi40 was +1.5 dB and Lsi9 is +4.5 dB.
I started testing the result of LSi9 but I’m so disappointed with its performance. The same problem that’s inherent in LSiC, the Left/Bottom woofer just vibrates there is no audible sound.
I checked if there is any connection loose in the speaker terminal or the woofer and everything seems fine.
So I searched the forum and found a hint to notch up the center volume by few dB. So I did and the lower dialogue improved but then the high freq is too loud and the sound seems very unnatural and unbalanced.
I also tried using the LSi9 as main speaker after unhooking one of the fronts LSi15. The same problem persists bottom woofer just vibrates while the LSi15 output is quite noticeable.
What should I do?
1. Return the LSi9 and get the LSiC. What if I have the same problem with LSiC as well?
2. Return the LSi9 and use CSi40. I know it’s gonna be a timber mismatch. But if I get LSic and have the same problem then anyways I will end up using CSi40
3. Do you think somebody might have replaced the crossover in LSi9 with an LSic crossover and sold it to me? How do you differentiate between the Lsi9 crossover and LSic crossover? BTW I have an LSiC crossover that I got from the forum member as a freebie. Do you think I should try that as a last resort?
4. Buy an LSi9 crossover and try it? I don’t know if I can buy it.

I’m really surprised my experience is opposite to the people who are using LSi9 as center and are happy about it.
If you guys have any feasible solution up your sleeves PLEASE help me out. I know this topic has been covered here before and I did go thru all the possible posts on the forum but could not find a satisfying answer.
I was up until 2 AM last night figuring out the problem. I only slept few hours and currently dosing off at work. I would really appreciate the help.

lomic

LSi9:
Crossover Driver 1: LPF at 200Hz 12dB/oct,
Driver 2: LPF at 2.4kHz, 12 dB/oct.
Tweeter: HPF at 2.4kHz 18dB/oct.

LSiC:
Crossover Driver 1: LPF at 200Hz, 12dB/oct.
Driver 2: LPF at 2.4kHz, 12dB/oct.
Tweeter: HPF at 2.4kHz, 18 dB/oct.

LSi15:
Crossover Driver 1: HPF at 150Hz 6dB/oct, LPF at 800Hz 12dB/oct.
Driver 2: HPF at 150Hz 6dB/oct, LPF at 2.4kHz 12dB/oct.
Tweeter: HPF 2.4kHz 18dB/oct.

I think people like the 9 as a center simply because the larger enclosure presents a "larger" sound and it extends a bit deeper more easily. As you can see from the xover specs, they both (in theory) have the same cascading xover between the woofers. If you have voices eminating equally from both woofers, from my experience, it kills the "horizontal dispursion" as Polk calls it, and makes voices sound unnatural if you're not in the sweet spot.

Personally I like it - unless I go up and put my face infront of the LSiC, I can't tell voices are only eminating from the right woofer - and now I can sit anywhere on the couch and hear dialogue clearly.

Mazeroth

Your speakers are fine. You are experiencing what you're supposed to be hearing

wingnut4772

Did you buy it used from someone? If you bought it used anything is possible. You should not be hearing a tremendous difference between the 15 and the 9 .More low end on the 15 of course.

Remember the 9 is 4 ohm so it will be set higher than your previous center but it should be on par with the 15s. I like to set mine a tad hotter but that is just my preference.

Give it some time and see if you adjust to it. If not , and you can, return it and try the LSIC.

malikarshad

Originally posted by Mazeroth
Your speakers are fine. You are experiencing what you're supposed to be hearing

Yes I read the cascading theory and I understand why only one woofer is dominant.
But why there is a clear difference in volume between CSi40 and LSi9. I have calibrated both speakers accordingly.
With CSi40 the low vol. dialogs are clearer while LSi9 i don't hear it well.
I played one scene over and over again to listen for the differences in the vol. and woofer movement between CSi40 and LSi9.
Both the woofer in CSi40 has audible sound while in LSi9 only the right has audible sound. Even my wife noticed it. Both have Cascaded design. Why the difference apart from the crossover? They should perform identical!!!!Right?

Or is it that it will take some time for me to adjust to it. I think it does not matter if it’s an LSi9 right or left channel speaker. But I have the Lsi9 right channel.
So your suggestion is to keep LSi9?

Dennis Gardner

You are experiencing the intended design of the LSi line.

Put your speaker grills back on and enjoy the great sound once the system is calibrated. If you feel the LSi lacks punch then you may be more happy with the RTi lineup, as they have more dynamic punch for movies. The design of a tiered midwoofers has been done to create a better soundstage and eliminate problems that Polk felt other center speakers had. If you require bass from the center as strong as your towers, you may want to run your center along with a small sub to bump the bass in that area or find an old CS1000P.

Dennis Gardner

The LSI speaker is a 4 ohm design that gives 3db more volume with same power compared to your CSi40 which is an 8 ohm nominal speaker.

PolkThug

The Csi40 is a great center-channel speaker, if it sounds better, then use it. I only got rid of mine for cosmetic reasons, to match the newer Rti's.

PT

malikarshad

Originally posted by Dennis Gardner
You are experiencing the intended design of the LSi line.
If you feel the LSi lacks punch then you may be more happy with the RTi lineup, as they have more dynamic punch for movies.

I guess I'm in transitional phase from Rti -> LSi. Did anybody else experience the same thing?

If you require bass from the center as strong as your towers, you may want to run your center along with a small sub to bump the bass in that area or find an old CS1000P.

The SVS Pb2+ is more than enough for the bass department. No complaints in the bass department.
How much hot do you guys run your LSi9/LSic after calibration? I read on the forum about 2 db. I had Lsi9 at +4.5db after calibration and notch up to +6.5db and sometimes its too loud on certain passages.

Dennis Gardner

My more bass comment, comes from your concern that you didn't think you were getting all the sound that the 9 had to give you in the bass department since you could see that one of the woofers was loafing.:) due to its design. You aren't lacking in the bass department with the big SVS you have, it seems that your concerns are more with the inherent design of how Polk put the LSi line together. I do think that the cascaded design shows up more in the LSi than the CSi models. I am sure this is a design function of the crossovers not really a flaw, just the way they made 'em.

I have tried both RTis and LSis and find that the RTis work better for movies while the LSIs shine for music. No flames please, just my opinion. I like my SDAs best for 2 channel listening than any Polk I have tried.

Mazeroth

Something else to consider. The LSi9 "bass" woofer plays up to 200hz, while the same woofer in the LSi15 plays up to 800hz. This means from 200-800hz, the LSi15 has 2 woofers playing, unlike the LSi9 that only has one. This makes a lot more sense to me. It's like having a 0.5 speaker taking care of baffle step compensation. I have no idea why Polk didn't up the hz. on the "bass" driver to 800hz like they did on the LSi15. I think that would have sounded much fuller.

malikarshad

How come there is no cross over specification for CSi40 on polk site.
http://www.polkaudio.com/home/specs.php?recent=1&category=5&speaker=183
I found it on the online manual
CROSSOVER FREQUENCY:
2.5kHz
CROSSOVER SLOPE:
2nd Order HP,
2nd Order LP

I was surprised to read that CSi40 is not Cascaded Array design. I guess this might be the reason I'm noticing the difference.

VR3

You need...more...power...

Your Denon...cant do it. period.

malikarshad

Originally posted by Vr3MxStyler2k3
You need...more...power...

Your Denon...cant do it. period.

Sid wake up... ;-)
I'm running it with OUTLAW 770 300W x 7 at 4ohms load.
Do u think I need more power than this

scottnbnj

Originally posted by malikarshad
I guess I'm in transitional phase from Rti -> LSi. Did anybody else experience the same thing?

i went from monitor 7's w/ peerless tweets to lsi9's. the 9's gave me the meat of the change i was looking for in spades, but there were differences that changed the way i listen that i didn't expect. i didn't have preset eq trims until recently, but i can see how they could soften the landing for some and they help me on tunes that don't mate well with lsi's.

for driver movement, just get used to it, that's how it is. but, for the tonal balance of lsi's, it is an art/technical decision of the designers, much like the radically different tonal balance decisions that recording studio's create from one to the next. for a lot of music the lsi's tonal balance is perfect, though for others it is off, just like any other speaker.

)

malikarshad

When you lay LSi9 horizontally do you keep the tweeter on the topside or the downside? I feel stupid but you never know until u ask. Currently I have the tweeter on the topside.
Thanks for all your responses.

Dennis Gardner

On the topside if your ears are above the speaker just as the 9s have the tweeters on the inside to avoid having the highs cross through the midranges soundpath.

malikarshad

Originally posted by Dennis Gardner
On the topside if your ears are above the speaker just as the 9s have the tweeters on the inside to avoid having the highs cross through the midranges soundpath.

I think u meant if the speakers are above the ear level.

Anyways I have ordered a LSiC today and should be here in a weeks time. I'll have to test it out and see who wins.
Well I'm atlest getting used to Casaded Array design.

Who do you think will win in a center channel roundup of LSi9 or LSiC? Any votes.

Thanks for helping me out.

Dennis Gardner

Tweeters are generally placed on top of most center speakers in theory to avoid the distortion from the woofers. That was my intended message. Good luck with the LSiC.

DG

lomic

Quick question... is your center sitting directly atop of your TV? I was able to fix my last LSiC problem with a 97 cent pack of Elmer's Tac n' Stick (same as Blu-Tack). I'd previously had a real problem hearing voices at a certain frequency as they appeared to resonate through my TV - it was really annoying me and I knew it didn't make sense so I looked a bit into vibration isolation.

The problem seems to be gone now and all my dialogue is crystal clear, I think it even helped clear up other frequency pits I didn't even notice before.

wingnut4772

I think the 9 will win out. It really does sound better IMO.

malikarshad

Originally posted by wingnut4772
I think the 9 will win out. It really does sound better IMO.

That's what I'm hoping for and I won't have to go thru the trouble of selling a single LSi9. I guess selling LSiC won't be a problem. Let's see what happens.

The Center is not directly on top of TV, its on top of entertainment center. But its a nice suggestion I will try that too.

malikarshad

So who is the winner LSiC vs Lsi9.
Watch the result..






















And the Answer is.................






















LSiC.
Played for a couple of days and LSic wins for its wide dispersion. With LSi9 the sound was focused to the sweet spot and off axis did not sound as good as sweet spot. And I have other people sitting off axis so for my need LSic works out best. I did not find LSic lacking anything compared to LSi9.
So why not use the speaker what its meant to be used as?
I know other people has different experience than mine but as its said every room is acoustically different.

Whadyasay

Originally posted by lomic
Quick question... is your center sitting directly atop of your TV? I was able to fix my last LSiC problem with a 97 cent pack of Elmer's Tac n' Stick (same as Blu-Tack). I'd previously had a real problem hearing voices at a certain frequency as they appeared to resonate through my TV - it was really annoying me and I knew it didn't make sense so I looked a bit into vibration isolation.

The problem seems to be gone now and all my dialogue is crystal clear, I think it even helped clear up other frequency pits I didn't even notice before.

This is a very common occurence that a lot of people aren't aware of. If you rested your main speakers on a hollow plastic box, you wuold most definitely notice a difference for the worst. Rear projection TV's and CRT's are verry resonant, and a good deal of energy can be lost through that. I use rubber feet and doorstops to hold/tilt the center speaker, and I have also stuck some anti-vibration material over the rear outer surfaces. This definitely helps tame the resonance from the speakers and sub.

I'm very happy with my LSiC. Somewhere down the road I'll get a new TV, either a plasma or DLP rear proj, and I'll probably try to reconfigure my system placement so that I can mount the center speaker on a stand.

newsman

malik thanks for your follow up! With all the recent posts about LSi9 being superior to LCi as a center speaker, I started to wonder if I need to experiment with LSi9 xover. But now I guess that LCi is indeed a better center. Still, I think that Polk should make a better, no NEEDS a better center channel speaker for LSi line. 2 5in woofers just don't cut it for a reference center. My RTi400C - now that was a center! It was big - but it had full sound and never showed any sign of strain. But you have to realize - it had two 6 1/2 woofers and same goes for CSi40.

wingnut4772

I prefer my LSI9 as a center by a longshot but I am always in front and anyone else watching is also.