Box and sub advice

[mikecdm 0]

Hello, I have been thinkging about buying a new sub and one of the members of another forum I visit is always raving about Fi subs so I decided to have a look for myself. I have been trying to read up on the forum and think I have decided on a sub, but I am not too sure about the box. Based on what I have read it seems that a 12" Q is what I am looking for. I want a good sounding sub with the ability to play low and loud. I only really want 1 sub as my trunk space is limited and I'm not trying to win any spl competitions. Basically it will be in my daily driver.

Right now I am still in the research stage but have no clue about a box. I don't know if sealed or ported and I have never made a box before in my life. Seems like a sealed box would be a lot easier than a ported box, but who am I to say. The tuning and port is what confuses me about a ported box. In the past I have mostly had sealed boxes with 2 subs. Right now I currently have my sub in this tube thing which I dont like, or maybe it's just the sub. In my car I have had maybe 3 different sub set ups with my current one being the most dissapointing. Its a kicker comp vr and said to say that it sounds worse than the audiobahn I had before.

At the moment I have a cheapie amp, I have had it for around 5 yrs and has served me well. Well worth the $150 IMO. I hope to or plan on using it with the Q until I can get a better and more suitable amp. Its a performance-teknique icbm-782, supposedly it can output around 700watts when bridged but I doubt it. It has been able to push 2 12" Ma Audio's that were around 600 watts rms.

As far as my car and trunk space. I have a bmw 325 sedan with a rather small trunk. I'd still like to have some usable trunk, just like I do now. I'd like to keep it around 30"w max, 16"h max, and 18"d give or take a few. If I were able to get a box with the rear slanted I'd have a lot more room, but I have no clue as how to make a slanted box.

Can anyone give me any advise, will my amp work with a Q? Will a ported or sealed box be better for my needs?

Thanks for taking the time to read this, and hopefully for any advice.

[theabunai 3]

Your amp will work with the Q

but if you plan on staying in that wattage range don't rule out an SSD with copper coils....

A sealed box will yield a smoother rolloff (which means that all frequencies will TRY to be played on an equal playing field without one freq peaking more than another)... Sealed is more forgiving with mistakes so yes it is easier to calculate (ported is harder to calculate but both take the same amount of effort to put together physically)...

Ported will yield a peaky response usually targeted at the freq you desire causing a peaky response (which means when that freq is played it will be louder the then rest of the range)..

Figuring out the ported enclosure port length can be done with online programs such as this

http://www.subwoofertools.com/forum/ported-box.asp

Just fill in the info from ficaraudio.com web site and it will calculate it for you

Sealed also has a forumla to achieve a flat response (usually with a QTC of about .707)

You can do that here

http://www.lalena.com/Audio/Calculator/Box/

Pay close attention to metric values and standard values it is very important...

it will spit out a volume result needed to achieve the smoothest possible rolloff for sealed enclosures...

remember the when computing enclosure take the NET (or inside measurement) of the box and subtract the woofer displacement (once again found on ficaraudio.com website) for TRUE volume of the enclosure....

[mikecdm 0]

THx, that seemed to have cleared up a few things. I kinda get an idea of what the port tuning does now. THinking back it makes a little sense now.