"clacking" noise at high volumes

[Cuchulain]

I've had a new PSW125 for about 2 weeks and its been great. Been listening to music and watching TV until now. Its first big test was today with an action movie and it produced a "clacking" (for lack of a better word) noise on a couple of occasions. It happened on the biggest explosions; so when the most energy was needed. It has continued to work fine since this happened. It was turned up louder than it has been since I got it.

Does this sub just need to be broken in? Specifically, it has happened only with intense LFE signals.

Thanks in advance for any input.

[DSkip]

Sounds like you're pushing that driver beyond its xmax, which could destroy it. Turn it down some.

[Cuchulain]

Noted. Didn't think I had it close to it's limit.

[Face]

Try placing the sub elsewhere in the room. It may be in a null, which will explain why it's not playing loud but exceeding xmax.

[gdb]

That "clack" you're hearing is an actual bottoming out of the voice coil. Continued bottoming will alter (mushroom) the coil's shape, then scraping will follow.

[maxima]

If the sub is not place in a corner, you can try corner placement which will greatly increase its output. A possible downside is the bass may sound a bit "boomier".

[tonyb]

Probably a combination of both, volume and placement. Also, that sub isn't ment for a big room either, so if you have it setup in a fairly large room your turning the volume up to try and pressurize the room. Then when the big explosions hit in a movie soundtrack you'll bottom out the sub.

[Cuchulain]

Thanks everyone. I really can't move the sub as I ran the cable behind the wall when I renovated. It's kind of recessed into this window area.

It definitely benefits from being close to a wall/corner in this spot. I guess it was just a matter of me having a new toy and wanting to see what it could do. The volume was only two thirds up on the sub and set at -20dB on the AVR. The room is about 14' x 16'.

[Face]

Time to pick up a longer cord and experiment with placement.

[kuntasensei]

Or go ahead and realize that your room needs more subwoofage than the PSW125 can dish out, return it, and step up to one of the many non-Polk alternatives that will get you that kinda' output on the (relative) cheap (SVS, Hsu, ED, etc.). Just sayin'...

[Msabot1]

Either a voice coil taxed or source anomalies ! Worked fine except during those passages?

[Tbone289]

The volume was only two thirds up on the sub and set at -20dB on the AVR.

You might benefit from turning the volume down on the sub itself and recalibrating the AVR. You should try to get closer to 0 dB on your AVR. My PSW505 is set at about 1/4 max volume, and that gets me to about -3dB on the AVR, which is close to the same setting as my front and center monitors.

[tonyb]

Just off the top of my head, I want to say three quarters of volume is way too much. I don't think I ever had a sub where the volume was more than a tad north of half way.

Is the room enclosed or does it open on one side to another area ? If so, you may need a bigger sub to get some pressure.

[Cuchulain]

Either a voice coil taxed or source anomalies ! Worked fine except during those passages?

It did. Didn't think of 'source anomalies'; the disc was a dvd rip.

[Cuchulain]

You might benefit from turning the volume down on the sub itself and recalibrating the AVR. You should try to get closer to 0 dB on your AVR. My PSW505 is set at about 1/4 max volume, and that gets me to about -3dB on the AVR, which is close to the same setting as my front and center monitors.

Its turned down now but anything louder than say -10dB is too loud for the room. I don't understand 'recalibrating' the AVR. Do you mean changing my mains back to 'large'.

[Cuchulain]

Just off the top of my head, I want to say three quarters of volume is way too much. I don't think I ever had a sub where the volume was more than a tad north of half way.

Is the room enclosed or does it open on one side to another area ? If so, you may need a bigger sub to get some pressure.

Yeah the room is more open. the HT is only part of the room; the room is 25' in total with no door. Theater side is 12x14.

[Msabot1]

I think your equipment and settings are ok....more than likely the source! By the way,think Canada is cool..used to live in B.C.

[Tbone289]

Its turned down now but anything louder than say -10dB is too loud for the room. I don't understand 'recalibrating' the AVR. Do you mean changing my mains back to 'large'.

I mean turn down the volume on the sub, then run YPAO Sound Optimization calibration.

[Cuchulain]

gotcha Tbone, thanks.

[Cuchulain]

Done. YPAO set my mains to large which I reversed; set the cross-over to 120Hz which I changed to 80 and set the sub to +3dB which I left. Not sure what the previous sub setting was but with it turned down it has probably changed.