If you are using one speaker it doesn't matter.
yes there is. and it does matter. use a 1.5 V AA battery . use wires to connect the bat terminals to the speaker in a short burst. if the speaker cone moves forward then the terminal that you touched with the positive lead of the battery is the + terminal on the speaker.
Well what do you know?. I also thought it only mattered if using two speakers, so that one speaker is not out of phase with the other. When wiring two speakers to work in a stereo situation and wired differently, both will speakers work, but the sound is not best quality. That's what I always thought. I like the battery test idea, thanks.
It worked great, the amp is now finished, more or less, and it sounds pretty good.
it matters more for the lower frequencies ie low mids and bass.if wired opposite then on the thump of a kick drum the speaker will "suck in " instead of giving a push of air forward. giving weak bass response .
We are talking about the OP's, unmarked, undifferentiated speaker.
I am not convinced speaker polarity makes a difference in a guitar amplifier (compared with a bass guitar - not my area of interest). Looking on the www there are two groups with opposing views. Digging a bit deeper I found this article
"Dispelling popular myths... Absolute microphone or speaker polarity makes an audible difference."
The relevant part is towards the end and includes sound file links so you can decide for yourself.
Like the author of the article I cannot notice a difference. Probably my ears though (too much loud music through my Sony Walkman in the 1980s). :0)
I use a 9v battery if the speaker moves (out) first you have the polarity correct.
Yep, that's what I thought Timothy, in a stereo situation its best to have both speakers working in phase with each other, both cones moving in the same direction at the same time, for a more fuller sound. When related to the guitar, I see it as when the top and the back of a guitar are working/moving with each other, the sound produced is superior to a guitar where no thought was given in this area.
I'll jump on the other side of the wall, polarity on a speaker is an arbitrary convention you set and stick with to make sure they are in phase with each other when using more than one.
That kick drum 'thump' is about 25 push and pull cycles of the cone in and out.
from the speaker's point of view, current flows in from the purple wire, around the coil, out the blue wire, then reverses direction and comes in the blue wire and out the purple wire, then switches again.....like the pendulum on a clock. (just a whole lot faster)
but I like the idea of using a battery to check you are making the same assignments, though I'd either use a 1.5v battery or use a 10 ohm resister with the 9v so as to not melt the 44g coil wire on a 5 watt speaker.