Hey. I am unsure whether to build a sealed or ported enclosure for my Fi Q12 sub woofer. I am going to use it for music, not spl comps, and I mainly listen to hip hop with good bass. I would like it if it could go deep , but I also want a Flat frequency response, and good SQ (SPL is not my main concern because I think the Q12 is loud enough already)...
Are you sure you want a flat response? Have you ever heard a system that actually has a truly flat C-weighted sound curve? Most people comment that a flat response has no bass at all. Honestly with your tastes in music, I'd really recommend you order your Fi Q with the "Low QTS" option, the I heat ring, and "Cooling" options. Then, I would suggest you go with a ported box, 2.2 cubic feet in volume, with a 4" ID aero-port tuned to 28Hz.
That will give you a deep, resonant response for low end, while being very musical.
Thank you for the advice. I think I used the wrong word to describe how I wanted my subwoofer to sound (I'm still pretty new to car audio), With flat, I just meant that i want my music to sound as close to the original recording as possible...
I think i might go with a ported design, But are there any major differences between a square and round port?
Typically, flat would refer to the sound curve, and a sealed box gives a flat response, meaning the output stays relatively the same throughout the lower octave range. A ported box will spike in efficiency (and thereby have more output.. get louder) around the tuned frequency of the box, then it will drop off sharply below the tuned frequency. Gives more bass around, say 28Hz, but below that (which typically doesn't matter as much) it drops off sharply.
slot ports generally are able to move more air at high output, which is handy for SPL competitions, but a smaller, round port tube (for a 12" sub, typically a 4" ID port) will work better at lower volumes (prolonged listening volumes, let's say)
Okay, thanks. So you reckon a ported box is the way to go. I have a few questions about the tuning frequency. I have heard that you could seriously damage your sub if the frequency drops below the tuning frequency, I don't know if it's true. Also, there any disadvantages of tuning your port "too low". In other words: what would make an enclosure tuned to 35Hz better that one tuned to 25Hz for example?