sub reverse install

yea17s · Post by **yea17s** » Fri Apr 15, 2005 10:38 am

does anyone know how to put them in reverse style. do you just build the box as you normally would but put it in the wrong way, obviously before sealing the box

AcingTeam · Post by **AcingTeam** » Fri Apr 15, 2005 11:46 am

I would think you need special subs for it.

pehN · Post by **pehN** » Fri Apr 15, 2005 3:14 pm

AcingTeam wrote:I would think you need special subs for it.

No Way. You can put your subs just like you want em to be.

daewoo · Post by **daewoo** » Fri Apr 15, 2005 5:39 pm

also make the box a couple of liters smaller, depending on how big the sub is. as the sub won't be in the box you can make it smaller.

and yes, you can do that with any sub, could be you have to put the + on the - side and - on the + side so the sub blow there air the other way.

(not completly sure about that last bit, but i guess i'm right.)

lanos2001 · Post by **lanos2001** » Fri Apr 15, 2005 6:09 pm

you can do that with any sub but it is best if you buy subs that are "free-air" subs. they're specifically made for those types of applications.

nick

TheGreatAndPowerfulOz · Fri Apr 15, 2005 6:14 pm

lanos2001 wrote:you can do that with any sub but it is best if you buy subs that are "free-air" subs. they're specifically made for those types of applications.

nick

I beg to differ.

Any subwoofer can be installed inverted, not just free air.
Free air subs are best used with an infinate baffle installation.

As daewoo said, reverse the polarity of the terminals so that the cones still move in the same direction as they did before they were inverted.
Again, build the box to accomodate for the difference in internal air volume as the magnet and basket of the sub are no longer inside the box.
If you allready have a box, put something in the box to take up a little air volume. Some styrofoam or a brick work nicely.

Just make sure you use some adhesive to hold it down so it doesn't vibrate.

Cliff

daewoo · Post by **daewoo** » Sat Apr 16, 2005 12:39 pm

i certainly wouldn't use a free-air sub, there made to play with being in a box.

if you install your subs inverted you are still using a box. the sound will be 10 times better when you use a normal sub then using a free-air type.

yea17s · Post by **yea17s** » Sun Apr 17, 2005 6:20 am

i got two 12s, sony xplod, 1200 watt max 350 rms, there lp1250 or somethin like that, thanks for your help guys.

yea17s · Post by **yea17s** » Mon Apr 18, 2005 5:46 am

switchin the faze around (+ 2 -) wont that be bad for the amps, sending positive to negative

TheGreatAndPowerfulOz · Mon Apr 18, 2005 11:10 am

yea17s wrote:switchin the faze around (+ 2 -) wont that be bad for the amps, sending positive to negative

The amplifier sees no difference.
All the amp sees is an impedence load from the coil, because no matter which way it is connected, it is still just a wire coil inside the speaker.

MMamdouh · Post by **MMamdouh** » Mon Apr 18, 2005 11:35 am

TheGreatAndPowerfulOz wrote:
yea17s wrote:switchin the faze around (+ 2 -) wont that be bad for the amps, sending positive to negative
The amplifier sees no difference.
All the amp sees is an impedence load from the coil, because no matter which way it is connected, it is still just a wire coil inside the speaker.

if that so then why the sound quality is very much affected when you reverse the connections?? almost every sound system that i came accross that had reverse wiring got poor sound quality and the correction of polarity fixed the problem.

i am not a real electronics expert but i did some sound systems wiring when i was younger and found that to be so true... revers polarty affects sound quality.

MMamdouh

TheGreatAndPowerfulOz · Mon Apr 18, 2005 1:06 pm

mmamdouh wrote:
TheGreatAndPowerfulOz wrote:
yea17s wrote:switchin the faze around (+ 2 -) wont that be bad for the amps, sending positive to negative
The amplifier sees no difference.
All the amp sees is an impedence load from the coil, because no matter which way it is connected, it is still just a wire coil inside the speaker.
if that so then why the sound quality is very much affected when you reverse the connections?? almost every sound system that i came accross that had reverse wiring got poor sound quality and the correction of polarity fixed the problem.

i am not a real electronics expert but i did some sound systems wiring when i was younger and found that to be so true... revers polarty affects sound quality.

MMamdouh

If the sound quality is greatly reduced, then only one sub is reversed and the two subs are moving in the opposite direction of each other which causes cancelation.
When it is wired wrong, one sub moves out as the other moves in. This movement causes the sound of each sub to negate the other.
This is called cancelation.

If both subs are physically turned over, so the magnets are outside the box and the wiring is correctly connected, then the subs will move together and will sound the way they should.

Also, sometimes the subwoofers can be wired correctly, but may be out of phase with the rest of the speakers in the car. This can be corrected by reversing the polarity. Some amplifiers have a switch that says 0 - 180 which is a polarity reversal switch. You can try that switch in both positions and listen to which sounds better.

Cliff

daewoo · Post by **daewoo** » Mon Apr 18, 2005 1:09 pm

yup, that's right.