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bob newton
03-11-2005, 11:11 AM
I been reading a lot on the forum about polarity and phasing. Just one question that I can not find answers to.

If you take 2 speakers and reverse the polarity at the drivers, does it change how the speakers sound? Or does this all have to do with keeping speakers in phase

IE, If everything is connected correctly, will posative inward sound any different than posative outward? As long as all the speakers are in the same phase? :banghead: This polarity stuff is important but its enough to drive ya :screwy: :nutz:

Zilch
03-11-2005, 11:28 AM
"It doesn't MATTER"

Audio is AC. As long as the phase relationships BETWEEN drivers and systems are correct, they'll sound the same....

bob newton
03-11-2005, 11:37 AM
Thats what I thought! I just wasn't sure. I was wondering in my limited mind if maybe JBL had reasons for the posative producing inward motion on driver. Like maybe better sound or something. As I take it , there is no real sound difference, inward- outward, + or - as long as everything is in phase.

Thanks Zilch

DavidF
03-11-2005, 12:38 PM
There is a suggestion "out there" that absolute polarity- simply defined as what you hear out of your speaker system is in exact phase with the original musical event- is worth striving for. The reality tends to be that recording process and the reproduction chain (not to exclude your local power company in this scenario) are all sources of phasing deviance so it becomes practically impossible to maintain absolute polarity. Also, in the design of the speaker system, one or more of the drivers may be in opposite phase to one another (there is plenty of fun reading on this subject in the archives) to preserve some phase coherence around the crossover response overlaps. So if your electronic system, your speaker system, and the source of the music, are all marching together in phase, and suddenly you switch polarity on the speakers, there may a good chance you can hear a difference. Personally, I came to the conclusion not worry about it since there are too many imponderables involved.


David F

Mr. Widget
03-11-2005, 01:24 PM
Personally, I came to the conclusion not worry about it since there are too many imponderables involved.

Agreed!

However there are those that claim to be able to hear "absolute phase". Which is the term for this subject. The idea being that a struck drum skin causes a pressure wave that starts out in a positive direction and so it should be recreated that way. In reality in a multi mic'd studio there will be out of phase information caught on tape and reproduced as well.

One of my CD players has a polarity switch so it is convenient to flip the phase 180° on the fly with my remote... yes it does change the sound... is one inherently right? I couldn't tell.

Widget

bob newton
03-11-2005, 01:50 PM
One of my CD players has a polarity switch so it is convenient to flip the phase 180° on the fly with my remote... yes it does change the sound... is one inherently right? I couldn't tell.

Widget


WOW! Then it matters. It changes the sound? And I take it that you couldn't distinguish which was better? :spchless: Maybe you are hearing the stereo change. Did you try the 180 on Mono? So that just the phase is changed and not the channels? Maybe your remote is just reversing the channels.

Mr. Widget
03-11-2005, 01:56 PM
No it certainly isn't reversing the channels... that is a very obvious change. This is a subtle change that after a millisecond I could never pick. I tried many times by switching back and forth many times to loose count and keeping my eyes closed so that I couldn't see the indicator... I picked correctly about 50% of the time... I couldn't tell.

Widget

Zilch
03-11-2005, 02:00 PM
Next time I'm over there, I will remove the phase switch from Widget's CD player, thus resolving this issue once and for all.... :p

Alledgedly, it matters in recording and sound reinforcement, where the live source is producing sound as well. Even this makes little sense unless the speakers and the source are time aligned, and there's zero delay in the reproduction.

I have some information on this here. It's filed under "too esoteric."

I only pay attention if there's some reversal in the chain, like amps using pin 3 as positive, to make sure everthing gets it right in the end.

bob newton
03-11-2005, 02:06 PM
Next time I'm over there, I will remove the phase switch from Widget's CD player, thus resolving this issue once and for all.... :p

Maybe a good idea! Could my ears be out of phase too? :blink:

bob newton
03-11-2005, 02:09 PM
Well, from what I am gathering, phasing is important but + or - doesn't have a profound effect. Do we all agree on this??

Mr. Widget
03-11-2005, 02:09 PM
Could my ears be out of phase too? :blink:

Do you listen to JBLs? If so you probably are out of phase. Just ask any audiophile. :applaud:

Widget

bob newton
03-11-2005, 02:15 PM
"you probably are out of phase"

Awwwww, well maybe. Everybody gets old and out of phase! lol

:cheers:

bob newton
03-11-2005, 02:20 PM
esoteric." ??

YIKES Zilch,:wtf: is esoteric?:offtopic: lol

DavidF
03-11-2005, 02:35 PM
..."absolute phase". Which is the term for this subject.

Widget

Yes, thanks Widget, absolute PHASE. Absolute polarity is a bit redundant, no?


Next time I'm over there, I will remove the phase switch from Widget's CD player, thus resolving this issue once and for all....

We have only Widget’s word that the switch is even working.


DavidF