Logitech Z-680s... I need major monster MEGA help

[SeiSmoS]

Guys i must be cursed. The one speaker set NO ONE has problems with, i keep having the same thing go wrong. I'm on my third set, and this one too is experiencing the same issue.

Problem: as a result of certain bass tones (tones in certain songs), something in the rear of the sub begins to rattle... once it is initially triggered it gets louder and more pronounced over time, eventually becoming so bad that it can be heard over a very large spectrum of bass tones. I'm not crazy, when you return sets to CompUSA they test the systems before they'll make the exchange, and sure enough they were able to reproduce the problem. I'm at a loss for what is causing this failure in the sub unit.

Let me be clear: when i run music i never have the sub level above default, and most times it is below default... when i got this third set to be extra careful a lot of the time i am running the sub volume one notch above 0 ! as far as regular volume goes i run it a little over the halfway point. Windows and media player volumes i usually keep between 65% and full. so as you can see im not blasting these things into oblivion.

However, when the problem is triggered, i would say my volumes are: sub volume at default or a little below, system volume slightly over half, media player volume full, windows volume 75%.

With this third set, when i heard even the slightest rattle or buzz, i turned the sub volume way down, as well as turning the other volumes down a little too. But like i said once the problem is triggered, it is apparently too late. Even running the volume low and sub volume a notch above 0, the rattle can still be heard, although you have to be a little closer to the unit to hear it.

Synonyms for describing the sound: Rattle, buzz... it's hard to pinpoint the perfect adjective, but those two sum it up fairly well.

One thing I should point out: because the wire provided is pretty short, i went out and got longer speaker wire so i could wall mount the satellites. I replaced the z-680 wire with larger 16 gauge wire. Is it possible this wiring is triggering the problem? And if so, how is this possible since the speaker wiring has nothing to do with the sub tones being relayed via the control pod cable.

Guys I'm really at a loss here. These things have the best sound I've ever heard, and yet I keep having this problem with the sub unit. Frankly it's really depressing me, and I would like to understand why this is happening to the sub.

Some songs that trigger the problem:

Klint - Diamond

Better Than Ezra - Beautiful Mistake

Joanie Madden - Charlie Mulvihill's/The Conspiracy

I really hope someone out there can help me, boy do i need it!

Thanks,

SeiSmoS

[The_Saint]

I`m not a speaker expert but I have the Logitech z680.
I never had any problems with them, although I did a considerable amount of burn in.
at least a month.

I did not turn the volume up more then 1/4 of the scale and the sub was almost to zero.

....I have replaced the cables with Monster Cable 14 Gauge and don`t have any problmes with it either.

Other than that I don`t know what to tell you.

sorry

[Kuasimodem]

You might want to check into your power source. If the line voltage is low, the amplifier can cause clipping (squared off sine waves) in the output, especially in the lower frequencies. This clipping can be compared to connecting your speakers directly to a car battery, and that kills the voice coil in the back of the woofer. This is the most likely source of the buzzing/rattling sound.

[SeiSmoS]

Thanks for your responses.... Kuasi, if the issue is low line voltage how do i remedy this? And has this clipping caused permanent damage to the voice coil? Thanks again.

SeiSmoS

[TheDarkwolf]

I'm having the same problem as well. I am on my second set of speakers. I had the subwoofer connected to a surge protector and I connected it directly to the wall and it seemed to remedy the problem to some degree. The clipping disappeared at some frequencies but was still present to a lesser degree at others. Does anyone know if this damage is permanent? Also I have not heard any problems with the satellites, but if the subwoofer was underpowered could they be damaged as well?

[Bizkitkid2001]

I had this same problem, then I screwed back in my AC vent that was coming loose behind the sub. No more rattle

[TheDarkwolf]

Thanks I'll try that before I take them back to the store.

[pinipig523]

i thought there was something rattling inside my infinity 12" pc sub - and it was driving me nuts for a while.

i thought that it couldnt be my 4.1 promedias because whn i only had the promedias on - the klipsch sub had no rattles, but when i had both on - there was rattling.

i was too quick to blame the infinity sub - until i realized that the rattle wasnt from the infinity sub - it was my lian li case - i guess the aluminum wasnt fit too tightly together or something - but the whole case was rattling.

then i fixed that - then there was still rattle - it was my closet door. i fixed that also.

but i still have some rattle - its my window now (this is a 3 year old house- so it is not rinky dinky - believe me).

needless to say, the sub is overwhelmingly powerful at times - and i gave up.

[Bizkitkid2001]

Lol, i have my 680 sub sitting between 4 computers. I know the feeling of trying to figure out wich one is rattleing. The ac vent sits right above the sub ont he wall. Gets kinda noisy with the rattles when i turn it up. I tried everything from duck tape to velco to keep my cases from stop rattling but nothing work, oh well.

[Warheart]

Hi!
I have the exact same problem with my z-680 set,
buzz/ratteling at some frequencies, and it's gotten worse :-(
I think the sine wave clipping theory sounds plausible, so I'd
like to hear how this can be remedied, if anyone knows.
I'd also like to hear how the other ppl that had this problem have solved, attempted to solve it