At high volumes my 18 makes a hollow pop sound. It sounds like someone is flicking the dust cap of the woofer but louder. First I thought bottoming out, but it happens at frequencies where there is not high excursion. This problem also happened on my sa12s I had previously. So now I'm thinking it is my amp, but why would the amp make such a noise? Any ideas?

Coils read good, no clipping, constant voltage.

Edited June 8, 201213 yr by djtomczak

Man I have hdc3's. They've only popped like what you say on clipped kick drums. I hear it right at the center of the cone.

It happens on most of my demo songs, which I have looked at and they have no clipping. Kind of ruins the demo when your subwoofer is popping...

how big is your box,

how much power,

where is your SSF set.

Box is 7 cubes after displacements at 35hz. No ssf. Last checked out at 1780 watts.

Air leak maybe? Does it do it at lower volumes?

Nope, only high volumes. Box is leak free as well. I turned the amp down a tad and it no longer makes the noise, but I would rather have it as loud as it can go. The volume change is noticeable.

the box seems a bit large to me.. i like around 6 cubes, for higher power... but im not sure about that sub....

your demo songs are LOW right??????

no SSF is your problem IMO.

Ah! I just saw that...what frequencies is the noise happening at? Could be unloading. I know people say HDC's are made to play below tuning but...if you're at almost double rated power without a SSF then that could definitely be an issue.

Did the SA's have an SSF?

its a combo of issues...

too much enclosure volume for that amount of power, with no SSF, will no doubt cause this issue every time.. no doubt.