masterelyt

my set of hx250d subs arrived FINALLY and i got a special box that will fit underneath the seat in the back of my truck

so i go to put the subs in the box and they only make it about half way in because whoever designed the box designed it for some sort of shallow mount subs.

anyways i'm stuck with the box because it was a special order from bassworx and i've decided to make it work.... the only solution is to mount the subs with the baskets exposed

this works fine physically but i've been told by several people to reverse the polarity to the subs as well because they are firing backwards now...

i know this makes sense but my subs sound like absolute crap with the polarity reversed, there's a bunch of mech noise!

so i left the polarity the same as if i was to mount the subs in a regular format and it seems to sound pretty good like this....

any thoughts on inverted mounting and if i should reverse/retain the polarity?

Dilatory

iTrader: (1)

Why would you want the voice coil pulling in? Regardless of mounting a sub is not "designed" to do that.. it will, but inefficiently.

TL;DR Don't reverse polarity. Bad advice.

masterelyt

thanks for the reply, and that was the installer from the car audio shop that gave me that advice.... shows why i won't let them do any of my installs :P

Mr.DatSubishi

Music is A/C current, so your subs are constantly moving in AND out. it's not like a sub just pushes out again and again. A lot of decks and amps give u the option of running reversed polarity with a switch or setting. In some vehicles reversing your phase will dramatically change output, sound quality and the feeling of spaciousness or greater size of interior.

Some drawbacks of inverting subs are mechanical and air noise from cooling vents and pole pieces.

masterelyt

but it won't hurt anything to leave the polarity as it is with the sub inverted?

Mr.DatSubishi

No. It shouldn't matter what polarity is, but it can have a big impact on overall sound characteristics. Whatever sounds better.

Dukk

As mentioned above, the movement of the voicecoil and cone when referenced from rest is both forward and backward, not in a single direction.

In fact the advice from the installer was 100% correct.

Dilatory

iTrader: (1)

Solely speaking from personal experience; Every time I've heard polarity reversed regardless of mounting it immediately sounds like .

From a technical standpoint? /shrug

masterelyt

the music signal from the amplifier is a sine wave.... correct?

so shifting the phase 180 degrees (reversing the polarity) is just changing where the sine wave starts

this logically makes sense but why is the sound so different then?

Dukk

There is no technical reason for the sound to be different when changing the polarity of a speaker. That speaker's interaction with other drivers of opposite polarity may cause negative or positive effects to the overall sound but the sound of the driver itself will be the same.