What causes clipping?

I did some experimenting over the weekend.

The Spica's are not full range speakers and if I don't call them "small" speakers on the HK receiver, NO signal will be sent to the subwoofer. Granted that they are physically large speakers, but their range is considered "small".

The SW-200 are "stereo" L and R subwoofers which have two 10" speakers in each box. The HK sends out a pre-amp mono subwoofer signal cutoff at 100Hz, so I split this and then go in the L/R pre-amps on the Kinergetics amp.

I found an old Enya CD which had some good simple monotone bass notes which helped me diagnose a bit more.

I tried switching the L/R speaker cables from the amp to the speakers. The problem stayed on the right speakers after the switch. This tells me that the amp is not the problem, but the right speakers themselves are having a problem.

But here are some notes / questions:

1. The problem is that both 10" speakers inside the right speaker sub box are vibrating to their extremes causing a jackhammer sound. This originally sounded like out-of-control, distorted, popping in the bass movie scenes, but with the clean Enya monotone, it was a steady pounding noise and I could visibly see what was happening.

2. Although the right speaker set has this problem, it sounds perfectly fine until it gets turned up to a loud volume.

3. I can turn the left speaker sub up quite a bit more and get it to do the same thing.

So... does this sound like a problem with the right speaker set or possibly a small room problem? I was wondering if there is some effect I don't quite understand where the speakers aren't able to create the bass they are trying to generate which causes this over excursion problem and speaker jackhammer effect. If it is actually a problem with the speaker, what could it be since they sound fine up to a point?

Any ideas welcome. Thanks for all your help!

John

Robotman, for me I had to use a 5.1 out on the dvd player to the 6 ch. in on the receiver. What I did was set everything to large, sub yes,set the distances, effects and volume controls almost to the max. This is on the dvd player menu. Check also to see if your dvd menu has a sub freq. on it.

After that, then try to tweak the volumes with the HK. I believe the SW200 xover is 80hz. If you can, adjust the sub out freq on the HK to that. If you are finding out that the tweak volumes on the HK are at two extremes, fronts -10 center +10, go back to the dvd menu and make some changes. All this is possible if your dvd menu has the capability to do this.I know all of this is a pain, especially if you have to go through 4, 5 steps just to get to the audio menu on the dvd player as I had to do.

Try the other suggestions from above about placement and not plugging the amp to the HK. Also, if your are not sure about the condition of the amp and subs, try it out with a different receiver or system to be sure.

If these SW are acoustic suspension (sealed box..no vent) your box might have a leak. Tighten all the mounting screws on the drivers. Check for any other source of leakage.

Test the polarity of the drivers by touching the speaker wires to a battery. Make sure that the cones move in the same direction.

It is a sealed box. I don't see what I could tighten on the box. What are the drivers? An air leak would make some sense, although everything seems really tight on the speaker box.

What type of battery would you use to check polarity? I assume you mean compare the the left pair of speakers and right pair of speakers move the same direction? Or do you mean the two speakers in one box? I can also just try reversing the red/black wires on the right side and see if that makes any difference.

I don't have an expensive DVD. I'm just using a PS2 or TiVo as the source through an optical cable for movies. I also read in the HK manual that if you set your speakers to "Large", there will be NO signal set to the subs. I didn't confirm this, but I will.

I did try plugging into the wall and didn't notice any change in the problem volume point.

Thanks for all your ideas!
.

Robotman...The "drivers" are the things with cones that move in and out. Since your SW has a built-in amp I guess that you can't get at the amp output wires that go to the drivers. If you could get at those wires, a 9 volt battery momentarily connected to the amp output terminals (and therefore to the drivers) would verify that the two drivers in one box are not hooked up with opposite polarity. That would be a long shot but worth checking if it was easy.

Your sealed box could leak around the drivers. or around the amplifier if it is in the box as I suspect. Tighten the screws everywhere, and use silicone rubber sealant if the gasket is faulty.