Standard for Marking Speaker Polarity?

[Jeremy H]

Hi Guys,

I'm replacing tweeters in my monitors and I am wondering about phase.

The original tweeters weren't marked for polarity in any way that I can see - but the new ones have a splash of green paint near one of the connectors. The connecting wires from the x over are white and blue with the white one marked as negative at the x over pcb.

The mid range drivers have a splash of red paint on one terminal that is connected to the red wire that is marked positive at the x over pcb. Fairly clear

Obviously I can get correct phase between the tweeters left and right - but am not sure about phase between the tweeters and the mid range drivers.

Is it customary to mark (identify) the positive terminal on speakers or is there no reliable standard?
thanks

[rick]

i have a a very rare and expensive ( once) emt polarity gun , that checks that stuff,
if you feel like lugging your speakers over to us we could check them for you in about 2 mins

[otto ruiter]

If you know the crossover frequency for the mid/tweeter, you can send a signal of that frequency to the crossover. If they are in phase, the output of the mid & tweeter will add, if out-of-phase, they will cancel.

[Kris]

I have two speakers on my guitar rig but usually only use one. One day while playing with both speakers, I noticed that I had to stand in a specific spot to actually hear it. Any movement away from the sweet spot and all sound would basically disappear.

Anyway our sound guy did this cool test where he got a nine volt battery, opened up the back of my speakers and hooked the battery up to the leads.

When connected to the battery, one speaker pushed forward and the other pushed back. Instant phase test. We re-wired one of the speakers and, did the same test and both were pushing the same way. A little low brow compared to Ricks solution but it works!

[otto ruiter]

When connected to the battery, one speaker pushed forward and the other pushed back. Instant phase test. We re-wired one of the speakers and, did the same test and both were pushing the same way. A little low brow compared to Ricks solution but it works!

That works fine for cone speakers, but I wouldn't advise it for tweeters...

[Jeremy H]

Thanks guys,
Actually, I was aware of the "battery phase test" but as Otto suggested I was a little concerned about applying voltage to a tweeter and wondered if you actually could see a tweeter move?

However, I tentatively tried it with a 1.5 volt "D" cell - whilst gently feeling for the movement of the tweeter. In brief it worked OK with no apparent damage to the tweeter.

I also tried critical listening with the tweeter wired either way. When the tweeter is out of phase you can percieve it as the sound not being focused from the centre of the cabinet - sort of spreads top to bottom. Like when left and right are out of phase and the sound seems to move to the extreme left and extreme right with a hole in the middle.

anyhow, problem solved. thanks for your responses.