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So far all the car CD players that I've checked play CDs out of absolute polarity. I also discovered that my Acura 2001 CL 3.2S had the front passenger side woofer and tweeter both wired out of phase at the factory with all the other speakers in the car. That made monophonic AM sound terrible and stereo pretty bad as well. Many other Acuras have the same problem that my car. The fix requires removing the door panel and reversing the wires connection to the connector of the wire harness.George, Perfect Polarity Pundit™
Follow Ups:
It's important to note that every alien probe used on my brother George and myself have been conclusively to have the wrong polarity. In over 63 cases this has been true for both the tall grey and the shorter lizard type aliens. We have written General Kevin at Area 51 with our concerns and he has opened a file.Both George and I have spoken to the aliens about this as every probing with the wrong polarity probe causes months and months of horrible constipation. A proper polarity probe of course produces a luxurious and copious stool and we intend to use this in one of our polarity and astral travel related products.
You've been warned.
gregorylouis
Anal Polarity Pundit™
N/T
"Music is the can-opener of the soul"
Henry Miller.
This of course does not help frozen food fans...
You can't just switch wires around and "fix polarity" of loudspeaker and crossover combinations like that.If your only argument is that "it sounds better to me" then my response would be "whatever works for ya" and I would not argue with you further.
But the methology is technically incorrect and here is why:
If a second order crossover is used from, say, a midbass to midrange or tweeter, there is a 180 degree phase shift imparted by the crossover. The speakers wires are inverted to compensate for the PHASE shift imparted by the crossover, which get the designer an optimally flat response by getting phase back in the ballpark by switching polarity. If you REVERSE the wires you STILL GET the phase shift imparted by the crossover, but now your frequency response around the crossover point is going to look like a massive dip followed by a massive hump in the response. Further to that, you've made an even bigger MESS of phase (NOT improved or restored it) as you've changed the phase relationship of the driver you've flipped w.r.t. the crossover and all the other drivers in the system.
If you want a phase coherent system, you need to DESIGN and BUILD or BUY a phase coherent system. You can't take non-phase coherent (non constant group delay) designs and "fix" them by switching polarity of one or more of the drivers.
If you had a technical justification for the switch - let's hear it. That's another matter entirely. But if this is a switch based on the "belief" that if all the speaker + terminals are connected to red + wires for ALL speakers REGARDLESS of crossover toplogy and order of slope... then I don't believe you. Nor would any crossover designer or manufacturer.
This 'belief' about speaker connection is a sort-of "misnomer" that has morphed from SPECIFIC phase coherent designs (such as first order) or specific higher order designs (like Linkwitz Riley 4th order) to include other designs like LR12 and BW18.
The LR 4th order at 24db/oct. (LR24) is an interesting example. It sums flat at Fc (crossover point) and has zero lobing error (tilt) and displays REASONABLY good transient behaviour despite the 360 phase shift imparted and non-constant group delay. (360 degree phase shift is the reason all drivers are in the same polarity - but a 360 degree shift has non-constant group delay, where a 0 degree phase shift (found only in 1st order designs) has constant group delay.
Then look at a two-way second order design. Yes, we need to invert the tweeter, but this design makes far less "muck" of phase than a 4th order design - the group delay is LESS than that of the 4th order, even though the 2nd order requires the polarity flip and the 4th does not.
Moral of the story? There's more to it that simply "the way the wires are connected".
Advice? If you don't know about crossover design and do not have measurement equipment to verify your changes, I would not muck with factory provided crossover connection methods.
Cheers,
P
Dear Presto,I understand crossover theory and practice quite well and all you points are interesting but a bit misguided. If you restrict yourself to only classical crossovers then only a first order Butterworth is phase coherent. To hear absolute polarity at it best one should only use first order crossovers. A second order will make the actually polarity of the source irrelevant because some drivers are always in opposite relative polarities. But what ever crossover you use all drivers in a given frequency reange the left and right channels need to connected in the same relative polarity. So my point is that the right front door's woofer and tweeter were connected in the opposite phase as all the other drivers in their respective frequency ranges. It's a obvious miswiring of the wire harness. It's exactly as if you had the left and right channel speakers of your home stereo out of phase with each other.
Best regards,
George, Perfect Polarity Pundit™
Ha ha ha.Right. I said "unless you have a technical reason for..."
Sure. And you DO have a very good technical reason. It's wired wrong!
Didn't pick up on that little important tidbit of information there.
But it's still a great post for the REAL wire switchers out there! ha ha
Sorry. My bad.
Cheers,
Presto
Though with George, anything is possible.
nt
NT
nt
/
NT.
Hell's teeth, George can be tedious on this subject...Whilst I am in no way a great admirer of Clark Johnsen, I will concede that he has already probably covered all of the "polarity" issues (and probably to exhaustion level) in the past...
George, for God's sake stop trying to re-invent the wheel!...
Bill.
["Many other Acuras have the same problem that my car."]I hope you haven't been stalking the Acura dealers. Also, stay away from police squad cars. Trust me, they lack a sense of humor.
Unless DSP time delay is used to eliminate the effect
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Richard BassNut Greene
My Stereo is MUCH BETTER than Your Stereo
If you don't believe it makes a huge difference and cancels bass then you don't need a stereo. Since when does AM monophonic supposed to sound like stereo?George, Perfect Polarity Pundit™
Apart from that, it's a great post.
Dear markrohr,If you mean that either way the speakers in the car all need to be in the same phase then you're correct that it's a great post. Also when you listen to the radio the polarities may change so a way must be developed for the listener to invert polarity as necessary.
George, Perfect Polarity Pundit™
"If you mean that either way the speakers in the car all need to be in the same phase then you're correct that it's a great post."----No, George, I meant what I wrote.
"Also when you listen to the radio the polarities may change . . . "
----Just like your CDs. Because no one adheres to any standard, real or imaginary, for CDs or playback equipment, the knowledge that "So far all the car CD players that I've checked play CDs out of absolute polarity," is MEANINGLESS.
". . . a way must be developed for the listener to invert polarity as necessary."
----Because car playback systems don't have this capability, and never will, your information is WORTHLESS.
Apart from that, another superb post. (SARCASM)
xa
George,
Please check the polarity of all of the telephone lines in the US, and then report back AFTER you do so. We would be so greatful.Thanks
p.s. Don't miss any lines. Do them one-by-one.
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If I get in my car and start driving, and everyone seems to be going backwards, I know the stereo is in reverse phase.
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