LSiC Issues- Help Please

[Biff]

Hello gentlemen,

Over the past several months I have been making small upgrades to my home theater. One of my most recent purchases was the LSiC. This purchase was based on the idea that I would be continuing to upgrade my front sound stage with the LSi9's when possible. However, I have been extremely unimpressed with my center channel and was hoping you all could help me determine my issues. I frequent audioholics forum regularly and a couple of the members there mentioned this would be the place to get some answers.

My system is as follows:
-Boston Acoustics AVR7120
-Old School Sony Towers (to be upgraded)
-Polk LSiC
-Phase Tech. Teatro 6.5 surrounds
-Velodyne SPL1200 II sub
I know it is a mut of a system, but for the time being I need to make it work.

I understand the center is rated for 4 ohms and this is probably my problem; however, I am a little hesitant to attempt to run only one output on the 4 ohm load while the remaining 4 channels are running on 8 ohms. The sound that the speaker produces running on 8 ohms sounds very muddy and is sometimes hard to interpret during dialogue reproduction. I have tried a variety of different movies to test the center channel and really have not been pleased with the results. I have run Boston's automatic speaker testing and found that I needed to adjust the center channel to almost +6 db after testing to get the most out of the LSiC.

To say the least I was not impressed and am convinced I am not giving it enough power or have screwed up the wiring installation in some manner. I ran Dayton compression fitting banana plugs from the receiver with 14 gauge wire to the bottom set of female terminals on the back of the center channel. Furthermore, I noticed significant difference in the quality and volume of the sound when I compared the top female terminals versus the bottom terminals. Should I be running two sets of speaker wire to both terminals? Should I be trying to run a 4 ohm load rather than 8 on this channel? Any advice you could give would be most appreciated.

Thanks.

[F1nut]

Do you have the jumpers in place on the LSiC?

[ohskigod]

Jesse might be rght on the jumper thing. with the jumper attached, there should be absolutly no change in sound or quality hooking the center from the top to the bottom set of terminals. take a pic of it if your unsure about the jumpers (metal thingey that links the 2 sets of terminals)

in regards to the 4 and 8 ohm issue. as long as the reciever is rated to handle a 4 ohm load, it shouldnt be an issue. now the fact that LSi's perform much better when fed high current power from a seperate amp is a completly different issue (well get there once you figure out these other problems)

[Demiurge]

Yeah, I had the same issue on mine that I bought here as the jumpers were removed, and I still haven't gotten them yet. I have just put the thing back in the box and went back to my CSi40. I won't be pulling it back out until I get the LSi15s and the LSi9s anyhow. :o

In fact when it was hooked up I got no sound out of the left speaker. Only the right one worked. I even switched the speakers around, and that wasn't the issue. Any other suggestions? I would hate to think I got hosed out of $350 on a broken speaker.

[F1nut]

Without the jumpers in place, you'll only get sound from one driver.

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

You can use short lengths of speaker wire in place of the metal straps. In fact, using good quality speaker cable should result in better sound than the straps.

[Demiurge]

Without the jumpers in place, you'll only get sound from one driver.

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

You can use short lengths of speaker wire in place of the metal straps. In fact, using good quality speaker cable should result in better sound than the straps.

Jesse, do you know off-hand if I can order the jumpers from Polk CS? The ones on the CSi40 are too small for the LSiC. I tried swapping them to no avail.

[F1nut]

I'm sure Polk would send you a pair for the asking. Call Ken.

[Demiurge]

I'm sure Polk would send you a pair for the asking. Call Ken.

Will do, thanks.

[McLoki]

Demi,

If you cant get them from Polk, send me a PM. I have a few I'm not using I could send your way. (Karma like, of course)

Michael

[McLoki]

Biff - the 4/8 ohm setting on your AVR just limits current. It should sound the best on the 8 ohm setting, but you risk damaging your AVR with current overload if you get to happy with the volume control.

As has already been said, the speaker should sound the same plugged into the top or bottom of the terminals on the back. If it doesn't - are the terminals connected together? (they should be either with factory brass plates or with a length of speaker wire - either will work fine)

let us know and we will delve deeper into your issues, but there is definately something odd going on there....

Michael

[Biff]

I appreciate the quick responses. I will be away from the computer tomorrow, but will send some pics of my setup as soon as possible. I can't recall if a jumper plate was attached to the terminals or not. Should the plates have come mounted to the terminals from the factory or is that something I would have needed to pick up separately?

Sorry I can't be more informative at the moment. I will get back to you guys as soon as I can answer some of your questions.

Thanks again

[ohskigod]

should be on from the factory, but if you bought a floor model or something, who knows

get back whenever and well help

[Early B.]

Changing out the fronts will make a big difference in what you perceive is coming from the center channel. Once you get the Lsi9's, your system should sound much better.

Also make sure you calibrate your system correctly.

[RoosterD]

I have noticed a something similar with my LSI C. I don't really have the problem anymore, and I think it's because:

A) I now have the center channel and surrounds set to "small" (per Polk customer service recommendation). When set to large on movies like War of the Worlds, the center gets a huge work out.
B) Denon sound autosetup feature. It changes the frequencies that are sent to the all speakers to defeat any unwanted unusually loud frequencies.
C) I bought a decent DVD player. Went from Pioneer DV-434 ~$100 new in '99 at Costco to Denon 3910. :) Big difference in picture and sound. Especially sound.

[Biff]

Fellas,

Sorry it took so long to get back to you all. I have been out of town on business and only yesterday had the opportunity to take some pics of the LSiC.

I attached some shots of the wiring installation to the bottom set of terminals. The wire is 14 guage and terminated with Dayton compression fitting banana plugs. As you will see it does seem that the jumper plate is intact. I was hoping that it was going to be a simple solution, but it seems there is something more to my problem. Take a look a the pictures and let me know what jumps out at you. Any suggestions would be most appreciated.

17370

17371

17372

Thanks,

Biff

[zombie boy 2000]

It looks like you lost the "floating slugs" in the bananas and fed the wire through the side holes:confused: . The exposed wire might be causing a short?

[zombie boy 2000]

Unscrew the bottom piece from the top on each nanner. Run the speaker wire through the bottom piece and flare out along the sides of the threading. Screw the top piece back on. Everything should be snug as a bug, but give the wire a nice little "snag" just to make sure. Insert nanner back into binding post.

And make sure they're screwed all the way down. Looks like that top left one might not be..... (the jumper looks a little loose)

[Biff]

It looks like you lost the "floating slugs" in the bananas and fed the wire through the side holes . The exposed wire might be causing a short?

I guess my only defense to this statement is the fact that prior to installing the banana plugs into the binding posts, I had run the speaker wire directly to them. I began with the top set of posts and would get horrible sound, as stated before. Then, I switched to a direct run to the bottom set of posts with a bare wire termination. The sound was better, but it is still "muddy" and requires +6 db's to compete with the my fronts, which are fricking Sony's. I just can't figure it out, but thanks for the suggestions. I will keep toying with them, but if anyone gets an idea or sees something I am not, please speak up.

Thanks.:confused:

[F1nut]

At this point, I'd say you need to have it looked at. Contact Polk Customer Service.