anybody know where buy subsonic filter?

[lmxd5120 1]

hey my jbl 1200 amp doesnt have a subsonic filter and im going to run a fi bl 18in in a ported box at 32 herts anybody know where i can buy a subsonic filter? and also what to set it at

[jcarter1885 995]

I been searching all on the net for some, maybe its just to late and Im not searching right but I couldnt find anything for you. I know it is some out there, look up external subsonic filters.

[ulrisa 26]

Search for f mods, they are about 25 dollars and they go in line with your rcas. They have varying f mods depending on the frequency you need.