Reverse Polarity

[Clarion_Guy 10+ year member]

What differences is there if i reverse polarity on my basic sub setup (box with magnet of sub inside of the box) ....

should I not do this?? since i did not reverse the position of the subwoofer?

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[ss3079 5,000+ posts]

Originally posted by Clarion_Guy What differences is there if i reverse polarity on my basic sub setup (box with magnet of sub inside of the box) ....

 

should I not do this?? since i did not reverse the position of the subwoofer?

If your subs are not inverted, I see no reason to reverse the polarity.

- Steve

 

[Clarion_Guy 10+ year member]

Alright... I guess my freinds mixed me up....

He had said his subs were easily heard inside the car due to the fact of REVERSE Polarity..

he had an option on his Pioneer deck to do this....

 

[evo2k3 10+ year member]

yeah my pineer does that to...you can change it on the fly, and there seems to be little if any difference in human ears....reversing polarity just makes the sub play 'backwards' when it would normally going in, it goes out again usually only used to invert subs. i am not even sure why pinoeer put that option on there deck.

 

[Wonderbread 5,000+ posts]

little something called 'phasing'... due to the nature of sound (waves...) sometimes cancellation will occur with the subwoofer inpahse or out of pahse... just swap them around see which way you like it best... it will not affect teh way the driver sounds, just how it interacts wiwth the otehr speakers... when I get some time, i'm going to be checking my phasing with ALL my speakers...

 

[evo2k3 10+ year member]

Originally posted by Wonderbread little something called 'phasing'... due to the nature of sound (waves...) sometimes cancellation will occur with the subwoofer inpahse or out of pahse... just swap them around see which way you like it best... it will not affect teh way the driver sounds, just how it interacts wiwth the otehr speakers... when I get some time, i'm going to be checking my phasing with ALL my speakers...

what the hell kind of comment is that? there is no difference in the sound, just the way they interact?!?! thats got to be one of the dumbest things I have ever heard. now for a little physics.....ONLY waves of the same frequency (or within a few hertz) will interact....and by interact we are talking about the pricipal of super position, in phase the aplitude becomes greater (constructive interference) out of phase the the waves destructivly interfere lowering the aplitude of the wave. Now I dont know to many mid range speakers that make 30 hz tones, so the interference between the subs and other speakers and tweeters is neglagable. short of reversing the polarity on one sub and leaving the other normal (assuming they are pointed the same way)...they are going to constructivley interfere. In addition "phaseing" as you described it is not only determined by polarity (makeing a 0 or 180 degree phase) but also by the path difference from the two sources...in the case of the car it is the difference in the distance from your ear to each speaker cause a phase shift that cannot be compensated by reversing poliarty. High end head units have the ability to enter these differences and calculate the deley for speakers that are closer to you (and the delay is very very small!!)....so theres the physics lesson for the day, the interaction (not even the right word, should be inteference) of sound waves DOES cause a difference in sound as long as they are between the human audioable range (20hz - 20khz)

 

[Wonderbread 5,000+ posts]

so in teh end, you agree? just worded differently? perhaps more 'scientifcally'? I never claim to be a physics buff, hell I ahted it in school... but many many people try running hteir sub woofers and mids and tweets in and out of pahse with each other... sometimes, due to the acoustic nature of a car, it can make a difference... a sub will sound the same (it willproduce the same sounds in and out of phase, no?) but the interference changes, sometimes for the better, sometimes for the worse...

 

[evo2k3 10+ year member]

i agree with the comment about the subs only....worded differently, no....worded correctly yes. reversing polarity can only shift 180 degrees ...so it throws it out of phase yes....but thats not the only out of phase.

 

[Wonderbread 5,000+ posts]

that much I know..

what i'm saying is, out of phase CAN sound better.... CAN sound owrse... it all has to do with teh diferent acoustical properties of the vehicle and the enclosure.

 

[evo2k3 10+ year member]

what your trying to say:

running the speakers out of phase can sound better only in the case where this puts the sources in phase at your ear, for that purpose being out of phase (even though they really aren't) will cause constuctive interference and more volume.

 

[Wonderbread 5,000+ posts]

yes.

basically.

 

[Corsica 5,000+ posts]

Originally posted by Wonderbread that much I know..

what i'm saying is, out of phase CAN sound better.... CAN sound owrse... it all has to do with teh diferent acoustical properties of the vehicle and the enclosure.

I know I tested with the sub normal and inverted on my Pioneer deck for my 2 10's and it sounds much better inverted.

J