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is there a way to find out if one of the drivers in my speakers is wired out of phase? without taking apart the speakers? my speakers are 2.5 way and can be bi-wired (if that makes a difference).
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"What did the Romans ever do for us?"
Are you asking this because of some "absolute polarity" concern?
If a simple single section Butterworth filter were used with a woofer and tweeter, or a capacitor to the tweeter and an inductor to the woofer, and with both drivers wired with the same polarity, there is still a 90 degree phase difference between the two drivers. The human ear cannot detect this (though some would claim that they can). Such a crossover is called "minimum phase." As some already said the crossover topology and the individual driver responses might require that the polarity of one driver be reversed. If you reverse the polarity of a driver to have both wired the same polarity, the result might be anything but the drivers sounding "in-phase" and this can result in peaks or dips in response.
As Duke points out that may be design. If the phase alignment differs across the two speakers, then you probably have a manufacturing problem, and a phone call or email will find out which is correct.
"What did the Romans ever do for us?"
bass is not tight. when i reverse polarity on mid/woofer on one speaker, the soundstage collapses, but the bass becomes much better to my ear.
so i am thinking maybe some driver is wired incorrectly.
It isn't clear quite what you mean by out phase. If you mean out of phase by design (i.e. the tweeter moves out when the woofer moves) then that is almost certainly part of the design as Duke says. However, if you mean one of the speakers may have been misassembled then try switching to mono and bringing the speakers close face-to-face. If a driver is moving out when the opposite one is moving in then you will get little sound being pumped out the gap over the drivers frequency range.
great advise! thanx!
...take a 'D' battery and touch a wire to each end and to the speaker connections.
The drivers will jump out, or if one is out of phase, it will move in.
I've had multi-driver speakers where one driver was wired wrong.
The battery trick only works with loudspeakers without a cap in series
You cant tell if the tweeter is in phase or out with a battery
because DC will not pass through a series cap
Click is all you'll hear, and see nothing.
You'll likely confuse the poster with your incomplete answer.
He should ask the manufacturer or determine what order the crossovers are and then determine if the individual units are wired the way they are supposed to be wired.
Of course, I suppose there is nothing wrong with re-wiring drive units out of curiosity to see what it does to the sound.
thats ok. i am gona compare right speaker and the left. they better behave identically.
As I said, you need to figure how they are supposed to be wired...then make sure that that's how they're wired.
The engineer who designed your crossover selected the driver polarity that would give the best performance in the crossover region taking driver rolloff (and its inevitable phase shift), crossover rolloff (and its inevitable phase shift), and driver physical (and acoustic) offset into account. In some cases this calls for normal polarity for all of the drivers, and in some cases it calls for reverse polarity on one of the drivers.
Me being a dealer makes you leery?? It gets worse... I'm a manufacturer too.
Duke
This reverse polarity in one speaker by design.
Do they pack these two speakers in one box? Is it possible to do that accurately with so many speakers packed by unsuspecting packing boys?
This phase and polarity stuff is so confusing.I have read so many posts on this and am still wondering about it all.There was even an inmate who wrote a best selling book on it who was unfortunately banned from here.
I connect the red to positive and happily listen Who knows perhaps I have never heard what my speaker is capable of.
srdavis2K is correct.
Let me try to explain in a bit more detail what I'm talking about by using an example. Suppose we have a two-way system with a second order acoustic slope crossover; in other words, the inherent driver rolloff + electrical filtering = 12 dB per octave rolloff for both the woofer and the tweeter. To simplify, we'll ignore the effects of driver offset for now. At the crossover frequency, the woofer will be lagging the tweeter by 180 degrees, so with both drivers connected with the same polarity we'll get a deepn cancellation null at the crossover frequency. (In fact, this is one way that the designer often checks to see if his crossover is optimal; if there is no deep null with the drivers connected in normal polarity [for this type crossover] then he still has some work left to do.) Anyway the proper way to connect the drivers in this case is with the tweeter's polarity reversed, so that it's in-phase with the woofer in the crossover region.
Now suppose that the crossover frequency is 3.4 kHz and the tweeter's acoustic center is physically 2 inches in front of the woofer's acoustic center (voice coil location is an approximation of a driver's acoustic center). This 2" distance corresponds to 1/2 wavelength at 3.4 kHz, so in this case driver offset adds another 180 degress of phase lag to the woofer and puts the tweeter and woofer back in-phase in the crossover region... almost. Actually, the woofer will be one cycle behind the tweeter at the crossover frequency. If imaging is a very high priority, the designer might want to position the tweeter's acoustic center 2" behind the woofer's, which usually calls for some expensive cabinet construction.
Hope that threw more light than mud on the topic.
Me being a dealer makes you leery?? It gets worse... I'm a manufacturer too.
Thanks Duke.
I must someday watch the designers at work.That would be enlightening.The hand on handling of all those complexities in creating an art form within the laws of Physics.
Best Regards
Bill
i meant to say 'driver miswired'. like the drivers in 2 speakers are not wired the same.
Okay, thanks for clarifying, and sorry for the misunderstanding.
Here's what I'd suggest: Play some sort of test tone that's centered in the crossover region. One-third octave pink noise would probably be idea. Listen (or measure) to see which speaker is the loudest in the crossover region, and that's probably the one that's wired correctly.
If you don't have access to a test signal, play music in mono through the speakers and switch back and forth between them. If you don't have a mono switch and a balance control, then use a Y-adaptor from Radio Shack so that both channels get the same signal, and run one into left channel of the CD input and the other into the right channel of the AUX input. By changing inputs you can change back and forth between the two speakers. Whichever one sounds best, that's probably the one that's wired correctly.
Me being a dealer makes you leery?? It gets worse... I'm a manufacturer too.
Duke isn't saying that the two speakers are out of phase, but that one of the drivers (the same one) might be designed to be out of phase on each speaker. In other words, the tweeters and midrange drivers might be in phase and the woofers out of phase (by design) with the midrange and tweeter on the same speaker. You still hook up the + and - wires on your speakers the same. It should be transparent to the end user.
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