Quick Amp Question about Ohm

[Andyman001]

Yeah you'll want to wire them in series: (+) of amp to (+) of #1 speaker; (-) of #1 speaker to (+) of #2 speaker; (-) of #2 speaker to (-) of amp. This will give you 16 ohms. wire both cabinets like this and you can use them both. this will be 8 ohms.

[Chunkyzz]

You guys sure?!
Im afraid now lol...

Btw! I am not sure whice one is + and whice one is -,

I just saw where it is connected to the amp,is there a way to know for sure?
Like test it?

[Downunderwonder]

They will all be the same on each speaker hopfully. You can test them with a 9V battery to see the cones jump outwards when + is +, don't hold it on for a long time, just touch it on and off to see which way the cone jumps.

The way you have them wired you're lucky you didn't play loud or you would have blown up the speakers and possibly the amp with them. The amp is only happy with 4 ohm. 4 8 ohm in parallel is 2 ohm so potentially they would draw a lot of excess current out of the amp.

Parallel is the + of each connected together at the jack. Don't do that!

You need to change both cabs to series and then run the cabs parallel on the amp for safety. You could run a series cable arrangemnt but the speakers are only 50W apiece and your amp would have 200 trace watts which is more like 400 real peak thump watts driving 4ohms. Danger is your mddle name.

So swap the cabs to series wiring. Jack tip goes to + of first speaker, - of first goes across to + of second, - of second goes to barrel of jack.

When you set up the two cabs put them in a vertical stack. The sound will carry a lot better around the room and you'll hear yourself so much better.

I'm curious what you used for a design for your cabs? Was the original sealed and not ported?

By the way, I've never seen any 4x12 trace cab, let alone a combo. I'm wondering if someone put a bass head in a guitar combo.

[HolmeBass]

Well, so if it worked, maybe your amp is 4 ohm stable- as you wrote in your initial post. The problem is you won't be able to run both of your 212's together as that would be 2 ohms.

To rewire the a 212 cabinet in series, do this:

Go from positive terminal of of amp to positive terminal on speaker #1, then from the negative terminal on speaker #1 to the positive terminal on speaker #2, and then from the negative terminal on speaker #2 to the negative terminal on the amp.

[HolmeBass]

Originally Posted by Chunkyzz

You guys sure?!
Im afraid now lol...

Btw! I am not sure whice one is + and whice one is -,

I just saw where it is connected to the amp,is there a way to know for sure?
Like test it?

Red is positive, black is negative.

LOL only your wires are colored, not the speaker terminals. Just use the same terminal, like in your picture the right terminal, as positive on all 4 speakers when you wire up your cabinets.

[RickenBoogie]

whice is actually which. sorry, but you'll be better for knowing.

[Chunkyzz]

I know red is + and black is - but the amp is colored green and orange going into red and black,and only 1 or 2 speakers has a black cable solderd to them...since its going to be my first series soldering,i just dont know... Too much red cable on each speaker makes me dizzy....

Thanks alot guys! Ill do the modification and let you know what happend

[Downunderwonder]

Easy enough to make a do over of it and test each speaker.

By rights the tabs should all be the same polarity for each one but it's not completely unknown for speakers to leave the factory with bad polarity so you may as well check with the battery.

If the tabs are already soldered you may as well leave that wire in place and resolder wire to wire with heatshrink. Reason being you will heat up the speaker voice coil if you don't get in and out smartly, easy to do without a good hot iron and some skill.

The 1st speaker will have a wire going to both terminals of the jack right?
The 2nd speaker probably has jumpers from the 1st speaker right?

Get back and I'll walk you through it.

[Downunderwonder]

Series speakers:

amp- ....... - O + .....- O + ........amp+

Jack lead tip is +, barrel is -

[Chunkyzz]

the big 0 is the speaker right?
i will make a drawing of my cabs as i wire them correctly and upload the pic,and you tell me if im right =)

[Chunkyzz]

i did not understand the last thing you did....
pic will follow soon

[Chunkyzz]

here is a diagram done by me by what you guys said,if i get it correctly yes...
and if the + on my speaker is the correct place =)



what you say?

[Downunderwonder]

You got it.

When it's all done confirm all cones jump outwards when you +tip -barrel a 9V battery onto the lead that would be plugged into your amp.

[Downunderwonder]

Your extension lead better be long enough that the two cabs can stand vertical end on end or I'm coming over to kick you.