Alright, what exactly does it sound like when a sub gets overdriven?

Sometimes I think I am pushing the HSU STF-2 sub too far. It usually only happens in explosions where there are tons of bass. The sound that kinda bothers me is sort of an oscillating low sound. I'm not sure if the explosion is supposed to sound like that or not, since it only happens in explosions.

Its sort of a subtle noise, a brief oscillation in the sub sound, as if it got higher for a second. I'm not sure I want to explain it more because I don't want to make it sound worse than it could be. I probably am just being over concerned.

My question is, if I hear the sub bottoming out or clapping, will I absolutely KNOW it? What does that sound like? What does it sound like when you are "pushing the sub too far"?

Thanks guys!

Once you have heard the sub driver bottom out you will certainly know it. Just as you discribe it is a "clapping" sound. I don't know what you are hearing but this does not sound like it is bottoming out.

You did calibrate it didn't you?

I'm sure glad I can't over drive my EP500, but then again, not sure that is possible with my Denon.

Once I hear port chuff, I usually turn down the volume.

What you are describing sounds like the sub is distorting (the harmonics are higher frequency than the signal it is trying to reproduce) but not bottoming out.

Yea, I figured that much. Just wanted to be sure.

So, if I hear clapping, it definately will be an "Uh oh, that definately wasn't a good sound" sort of thing?

The port is about 2 and a half inches from the inside of the desk, maybe that is making noise. If you look at my dorm room thread for reference, I turned the sub sideways so the port is pretty close to the right drawer thingy.

Hsu recommends at least 3 inches from any boundry.

Hmm...I Moved the sub a bit. Lets see if it makes a difference on tonight's movie.


Edit: Can there be a distortion difference when upping the dial on the back of the sub and dropping the db level of the sub a few notches on the receiver? More power, or whatever. Often times in a movie I am not going to get up to adjust the sub.

It's possible the receiver could distort when the levels are set high (but unlikely). I try to keep the receiver settings in the +/- 5dB range just in case though.

Try this test.

If you have a SPL meter, go to that scene again and play it at a lower volume. Read the meter. Now play it again and again while increasing the volume. You should see the SPL meter increasing at the peaks at an equal amount. Once you start to see the SPL meter not increasing while you are increasing the master volume, you know your are reaching the limits of your sub. At this point if the volume level is not acceptable to you, you have two choices. 1) You can lower the level of your sub so you can increase the overall volume, or 2) Upgrade your sub.