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haveyouever
03-04-2006, 04:57 AM
Could I get the Polk Club assitance in regards to a friends HT arrangement that just doesn't seem to work for us? We both have a similar HT setup (Lsi15s, LsiC & LsiFXs). We've spent a lot time tonight trying to hunt down what was first thought to be a wire problem. We finally focused our attention to one of the LsiFx speaker ohm readings???... something doesn't add up?.. here's what I've got:

Lsi15s = 2 X 3.9 ohms
LsiC = 2.2 ohms
3 x LsiFX = 2.2 ohms
1 x LsiFX = 5.0 ohms ?????

Your thoughts?

mantis
03-04-2006, 08:07 AM
Well there rated at 4 ohms at 88db. All of them.

If your trying to drive a full Lsi series with a recevier thats not rated for 4 ohms then your gonna have clipping and dynamic problems. When one goes Lsi, one is looking for higher sound quality more audiophile. Why on earth try to mess it up with a under powered receiver?

My advise is get a high current receiver like the B&K 507 s2 or Rotel RSX1067 or go seperates. just about all other receivers fail to drive such nice speakers correctly,

Dan

Frank Z
03-04-2006, 08:45 AM
Here's a link that will answer your question...
http://www.epanorama.net/documents/audio/speaker_impedance.html

haveyouever
03-04-2006, 10:58 AM
Well there rated at 4 ohms at 88db. All of them.

If your trying to drive a full Lsi series with a recevier thats not rated for 4 ohms then your gonna have clipping and dynamic problems. When one goes Lsi, one is looking for higher sound quality more audiophile. Why on earth try to mess it up with a under powered receiver?

My advise is get a high current receiver like the B&K 507 s2 or Rotel RSX1067 or go seperates. just about all other receivers fail to drive such nice speakers correctly,

Dan

Hi Dan,
He's got a Anthem PVA 7 driving the speakers which shouldn't have a problem!!

haveyouever
03-04-2006, 10:59 AM
Here's a link that will answer your question...
http://www.epanorama.net/documents/audio/speaker_impedance.html


Good Morning!.. and thanks!!... let me look into this further.

jcaut
03-04-2006, 07:12 PM
If I'm understanding your concern correctly, it centers around the fact that one of the LsiFx is giving you a different reading on a VOM when you check resistance across the terminals, than the other 3. Though the reading you're seeing that way is not actual speaker impedance-- it's merely DC resistance, through the crossover-- it still doesn't sound right. I think all of the same speakers should read the same. It sounds as if there is a wire loose, or possibly a faulty component on the crossover board, on that one F/x. I'd call Customer Service and explain what you're observing to them. They'll help you track down the problem. What exactly is the problem that prompted you to check the speakers with the Ohmmeter in the first place?

Dennis Gardner
03-04-2006, 07:20 PM
Was that FX in a different mode? Bipole/Dipole? Just a thought, as I don't want ot grab a meter to check if this makes a difference.

haveyouever
03-05-2006, 04:53 PM
Was that FX in a different mode? Bipole/Dipole? Just a thought, as I don't want ot grab a meter to check if this makes a difference.

Thanks for your support!!... I checked the readings of an identical array of speakers at my local Tweeter dealer. There's something wrong this speaker, and the retailer is willing to swap it out!!... thanks again!!

haveyouever
03-07-2006, 11:03 AM
I should mention to close this thread...

Polk Audio had me open the LsiFx back plate to detach the driver circuit board, because basically they tend to repair the boards instead of sending back the complete speaker... once apart I found the problem. One of the induction coils had broken loose, a simple solder fixed the speaker!!... thanks again for you support!!!... thomas