I have 2 Fi BL 12's pushed by 2 strapped Alphasonic pma1200da amps in a ported 2.5 ft^3 box tuned at 34hz. I am getting a wierd reverberation from tunes that are higher in the scale. My frequency on the amp is set at 80 HZ. This is my first ported box, my smallest lowest powered system, and the first one in a daily driver...so there are too many varriable that I have no experience with to pinpoint the problem. Do I need to stuff the box, retune the port, or live with it? Thanks for any advice. It is a small problem and only noticable if you are listening for it, but I want it gone DJ
My evo is a 2003 VIII...I don't have any pictures as it is just my daily driver...nothing too special...mostly stock with a few minor engine mods and some ecu work.....The box is small, but not too aweful small...it sounds pretty good (except for the little resonation)it dosen't low as it should, but that is the trade off for keeping the back seat.
For what it is worth I have a show car that I put most of my extra cash in...don't laugh, but it is an older body style Hyundai Tiberon. I have done some extensive work to it...turbo..exhaust...lowered...it has no back seat and 8 JLW6V2 12's and 8 500W slash amps in it...I actually probably wouldn't be able to tell if it resonates or not
I understand that the box is too small...by about .6-1 ft^3 according to FI specs...pretty sure that that wouldn't cause resonance...it would just effect the output frequency (ie it won't go as low as it should) I have been wrong before though...but I knew this when building it...I built it to fit the trunk...My calculations could be off on volume as it is not a perfect cube and has some angles that extend into the spare well and under the rear strut bar...the 2.5ft^3 was my low end estimate it is probably closer to 2.9 ft^3 but I didnt want to do calculus and it didn't really matter because it is physically impossble to make it bigger without modifying the structure of the trunk..
lol, j/k. If u want though, I could build you a custom box for one of those BL's, that way U could get better bump and not be pressed for space. Also, add some polyfill to that, trick the woofer into thinkin the box is 25% bigger.
Usually if you get a weird high frequency rattle-like sound means a loose panel, something may have broken loose. I had a box that was breaking loose in one certain spot, only made noise at certain frequency, irritating to say the least. Polo..