Old sub buzz, help!

[TeslaBro]

I have an old rockford fosgate punch p2. Its paired with a fosgate punch amp as well. I've been dealing distortion or buzz for a few months now. Whenever the sub hits the 60-75 hz range it begins to emit an ear grinding buzz. It happens with other amps but doesnt happen outside of the enclosure. I first thought it was rattling against its composite box, so I put a silicone seal around it. That didnt fix it, fast forward a few months, when experimenting with it, I find that the buzz crops up when tightening it against its box. experimenting with tightness of screws moves the distortion to a different frequency. I dont know if the frame is warping or what, nor do I know how to fix it. Can anyone help?

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[dragon.breath 10+ year member]

Are you sure that it is the subwoofer, and not the box itself? A loose panel in a box can sound almost exactly like a blown subwoofer.

 

[TeslaBro]

Are you sure that it is the subwoofer, and not the box itself? A loose panel in a box can sound almost exactly like a blown subwoofer.

thats what i thought initially but it is a brand new composite coated box. If i completely unscrew the sub and put pressure on its edges while playing a 75 hz test tone, i can hear the distortion come back. Same effect happens when precisely tightening screws, there is a certain point where i can slowly tighten a screw and hear it slowly distort. (note the effect is very unmistakable and obvious)

 

[1aespinoza 10+ year member]

Same effect happens when precisely tightening screws,

The frame may be bent. Your tightening warps the bent frame causing the motor to rub on the voice coil. I have seen this happen with dropped subs and mounted subs. The motor shifts a bit and sub becomes sensitive to tightening or surround touch.

 

[TeslaBro]

The frame may be bent. Your tightening warps the bent frame causing the motor to rub on the voice coil. I have seen this happen with dropped subs and mounted subs. The motor shifts a bit and sub becomes sensitive to tightening or surround touch.

As far as i know, it hasnt been dropped. I did turn the box and pin it between two seats, shoving some towels between the box and one of the seats. That did do wonders for the vibration as it did appear the box was resonating some how. I also put more screws around the frame (it only had 4, now it has 8). The distortion is still there although its now only noticible at loud volumes, I also noticed my home-made seal was slightly thicker on one side so that might have something to do with it as well.