Problems with CSi40 -- Connections or Drivers?

JediCowboy

I have a CSi40 as my center speaker and it is Bi-Wired to my Denon 3802 Reciever. Center Speaker is set to Small.

A few weeks ago I blew the drivers on my CSi40 -- I could hear both of the old drivers scraping when I pushed in on the cones slightly, and Polk replaced both without question. The new drivers arrived today and I installed them with ease.

My CSi40 sounded wonderful immediately after I put in the new drivers when I ran the speaker setup and tested the levels with internal Denon Speaker Level setup. The test tone matched the sound that came from the other 4 speakers. I set all speakers to 75db.

I then put in the Avia DVD to adjust the levels a bit more. At this time the Denon switched to outputting the sound as a Dolby Digital signal as it should. The Volume knob was set around -15db as I started.

I began the first test, which is just the speaker identification test (Left Front, Center, Right Front . . .) As the test cycled to the Center speaker for the first time the Denon almost immediately did its self-protection shut-off. I heard no popping or buzzing from the center speaker. The whole system just shut off.

When I tried the test with the Avia DVD again, it did not shut off when I got tot the center speaker, but sound only came from the tweeter. However, when I hold my hand over either driver I can feel slight vibrations.

At this time I tried the internal Denon Level check again and only got sound from the tweeter.

I checked all the speaker wires and they seem fine and the connectiions look solid. I switched the top and bottom wires, and still sound only came from the tweeters with the larger cones only vibrating slightly. I checked the wires inside the speaker and they seem to be conneted firmly to the drivers. As a last ditch effort I *gently* pushed on the driver's cones -- no scraping sounds thankfully.

I'd love to call Polk Customer Service but the are closed now, and I will be calling tomorrow, but in the meantime woudl anyone have any idea what the problem may be? I'm at a complete loss.

F1nut

Sounds like a crossover problem.

JediCowboy

Meaning what? What should I do? Any way for me to fix it myself?

JediCowboy

I put the center speaker on the right channel to test it -- I still hear only the tweeter.

Looks like the problem is with the speaker itself, not the wiring.

F1nut

It's probably the crossover inside the center. Unless you're good with troubleshooting circuit boards, then no, you can't fix it. Call Polk CS and tell them what's going on and I'm sure they will help you.

Dr. Spec

I concur with F1 - the crossover failed and it is not allowing the signal to be passed to the drivers. Either that or it actually fried the new set of drivers.

Pull the new drivers and connect them directly (at a low volume) to the leads and see if they still play.

Doc

VR3

If the crossover fried them, heck if the drivers were fried it all - I am sure he could still hear some type of noise from the drivers. IE: Snap Crackle Pop! But he says he cant hear a thing, so I doubt thats it. I concur on what F1 said, crossover problem.......seems polk has problems with center channels and crossovers............

JediCowboy

Thanks, F1Nut and Dr. Spec. Your advice is wonderful as always!

Originally posted by Dr. Spec
Pull the new drivers and connect them directly (at a low volume) to the leads and see if they still play.

By connecting them directly I assume you mean touching the leads from the speakerwire to the contacts on the driver?

I'll be giving Polk a call later today when I get a chance and if Ken doesn't respond here in the meantime.

dorokusai

I agree with the fine gentelmen above. The crossover may have been the root cause for the driver problem in the first place. Replacing the drivers just eliminated one portion of it, now the real issue is apparent.

Polk CS is the route to take. Keep us updated.

JediCowboy

Polk Customer Service is, once again, wonderful. I just called and they said to send in the parts again. No Questions. Its probably just a bad crossover, but I'm sending in the drivers and tweeter as well, just to be safe.

This is a pain to be certain, but Polk handles problems with their products professionally and quickly. Way to go!

Dr. Spec

Originally posted by JediCowboy
Thanks, F1Nut and Dr. Spec. Your advice is wonderful as always! By connecting them directly I assume you mean touching the leads from the speakerwire to the contacts on the driver?

It might now be a moot point, but that is exactly what I meant.

NEVER do this for a tweeter, only for the 6.5 mids. The tweeter has such low power handling and excursion limits it might self destruct with a full range signal, even at low volume.

Doc

JediCowboy

Originally posted by Dr. Spec
It might now be a moot point, but that is exactly what I meant.

Yes it is, but only because I started to doubt myself. I can take the speaker apart with no problem to remove component parts, but once I have to start playing with electricity and try things that can cause real damage I defer to the professionals.

From what I read here, I assume the problem is the crossover. Just to be safe, however, I sent in the crossover, tweeter, and both drivers to Customer Service to test it all and replace what needs replacing.

I've been without my center for too long now and figured I may as well give them all of the parts to figure out once and for all what the real problem is. Only a week or two more and all will be happy again . . .

Thanks again, Dr. Spec. I'll let you know the results when I get the parts back. But for now its off to the speaker forum for advice -- The UMFs are nipping at me and I think its time to go to 7.1!