Help with loudspeakers/PA Systems.
 

Allright, I'll admit, I know next to nothing about speakers and electronic reproduction of sound, apart from what sounds good and what doesn't.

So here's the dilemma; I have a 150W PA system that had its speaker knocked out a few days back. I brought it to a local repair shop, they told me it was unsalvagable, and persuaded me to buy a new one (apparently it could withstand up to 350 watts of power).

As luck would have it, the other one burst within a day of use. Called the shop up, and the guy mentioned a phrase going along the lines of "the positive and negative polarities may have been reversed and caused the speaker to burst - did you reverse them?"

Well, I can't remember what polarity went where - and I really didn't learn anything regarding polarities in a speaker system in my Electronics Engineering diploma (as far as I know where speakers are concerned, there really should be no difference in polarity, at least for the small ones I used in some projects way back). Does this apply to all speakers or only the small ones?

Any help from audiophile gurus around here?

I would have to really see what model it is maybe so I could find the specs on the particular piece of equipment, but I own some audio gear and it can be ruined by plugging it into the wall with the cord facing the wrong direction thus changing the polarity. Make sure the prongs on the cord match the outlets in shape.

basically gives you a 50/50 chance of blowing it which is pretty good.

Do the polarities really matter that much? I mean, the speaker itself contains no silicon parts or transistors, so why does it burst even if I do switch polarities?

Let's start Physics 101 again!

Reversing the polarity of speaker drivers wouldn't blow them. If you reverse the polarity of one speaker while hooking the other one up properly, they'll sound very odd, and they still won't sound quite right if they're both hooked up backwards, but you can't blow one outright that way.

Flipping wall polarity can do bad things to an amplifier, but you'd be very hard-pressed to do that thanks to the wonders of polarized plugs. :\

By "switching wall polarities", do you mean reversing the live/neutral ends of the main power outlet?

Also, if did do that, shouldn't the whole system, speakers and mixer be unable to start in the first place?

Intriguing.