Buying 1 15" Fi Q need help with box build

 

New member
Username: Honeybadgerbob

Post Number: 2
Registered: Aug-13
alright so my 2 12" infinity reference subs finally blew after a 5 year run and only cost $200 for the amp and subs and the box.

ive decided that im going to buy 1 15" fi Q first question is will it sound better than my 2 12s even tho its just a 15? and for a box ported or sealed? i drive a 2002 buick lesabre, my trunk space is

38" wide
16" tall
16" deep

i still want room for grocerys and still be able to enjoy some bass with my music i already miss it and its only been a day


sorry for no puncuation lol.
 

Platinum Member
Username: Glasswolf

Columbia, South Carolina America

Post Number: 14876
Registered: Dec-03
you can tailor an Fi Q subwoofer to meet your needs, sealed or ported, based on the options you choose for the sub.
I run a Q15 sealed in my own car. If your subs blew, you have a problem. Subs shouldn't ever blow, unless you have the gain set too high on your amplifier, or the amp isn't getting sufficient current from the electrical system, causing the amplifier to clip, or you had some other issue, like running a ported box without a subsonic filter.
 

New member
Username: Honeybadgerbob

Post Number: 3
Registered: Aug-13
i think im going to go with a sealed box, with the demensions i listed what would be a good size box to use? and is 16" not enought height on the box if the sub is facing forward towards the opening of the trunk. itll only give it .5" on each end
 

Platinum Member
Username: Glasswolf

Columbia, South Carolina America

Post Number: 14878
Registered: Dec-03
interior or exterior dimensions?
double baffle the face of the box where the sub will be mounted, to support the structural weight of the driver
you'll want about 3 cubic feet of ait space inside the box (AIR space.. that means after you add in the displacement of the speaker itself)
If you went ported, it'd be more like 3.5 cu ft plus port and driver displacement and you'd want the port tuned around 31-35Hz.
Use 3/4" MDF or HDF to build the box, reinforce the box internally, and screw and glue it so it's strong.
Typically for a sub enclosure, you want half the diameter of the driver's distance between the magnet and the opposing panel of the box, so if it's a 12" sub, you'd want 6" between the speaker magnet, and the back of the box, for example.

that should get you on your way to making a box. www.bcae1.com has some great tutorials on box building basics.
 

Gold Member
Username: Joe1234

Post Number: 1854
Registered: May-09
In a trunk car you want to avoid firing the sub up so at least 16 1/2" tall box, also you are not mentioning what amp are you using, you do have enough space for either ported or sealed.

Do sealed for a flatter response / lower group delay and ported for increased efficiency.

As for "sound better", that really depends on what do you mean by that, output wise those little cheap subs are not likely to overtake the Q15.

Lastly that is a 1500W RMS sub, you will need some electrical upgrades to run it loud on a daily basis.
 

Platinum Member
Username: Glasswolf

Columbia, South Carolina America

Post Number: 14881
Registered: Dec-03
I dunno.. my Q15 is firing upward, fiberglassed into a sealed box where the spare tire goes, and my car has a trunk (fastback '66 Charger) and it sounds pretty good. I can drop the divider between the trunk and cabin, though so the car is open clear to the tail lights.

Typically in a sedan though, I do like to fire subs rearward
 

Gold Member
Username: Joe1234

Post Number: 1855
Registered: May-09
With larger diameter subs at least it's very frequently the case that drivers are placed almost right against the trunk lid, forcing to use heavier deadening and likely reducing efficiency, sure in the right conditions sub up is an option.
 

Platinum Member
Username: Glasswolf

Columbia, South Carolina America

Post Number: 14882
Registered: Dec-03
yeah I was lucky in that regard. With the sub in the spare tire well, it's pretty much invisible, and leaves the entire trunk as a chamber.

http://www.glasswolf.net/stuff/cars/charger/trunk01.jpg

http://www.glasswolf.net/stuff/cars/charger/interior01.jpg
 

New member
Username: Honeybadgerbob

Post Number: 4
Registered: Aug-13
as of right now id be running the 15" Q off a hifonics 1000 watt mono block amp, until i can get a better qaulity amp such as an orion 1500 watt amp or a sundown audio 1500 watt amp, im definetly gonna upgrade my big 3 would i still have to do that even if i have an extra battery in the back? hopefully ill be picking up the sub either the end of this week or next still trying to look into a box design thinking of going sealed instead of ported seeing as how ill build the box myself
 

Platinum Member
Username: Glasswolf

Columbia, South Carolina America

Post Number: 14883
Registered: Dec-03
to answer that, read the sections on the link below labelled "electrical"

http://www.glasswolf.net/papers/index.html
« Previous Thread Next Thread »



Main Forums

Today's Posts

Forum Help

Follow Us