before i get shot down in flames for not researching, i've looked on google and at previous forums posted on here in the UG archive and it's just technical mumbo jumbo that i cannot for the life of me understand :')

all i need to know is (in novice language) what ohm setting should i have my peavey jsx on whist running through certain cabs? i just need to know because i dont really want to be blowing up speaker cabinets while im playing live in my band... haha

probably a simple question, so gimme a simple answer i don't really mind if i dont understand how it works i just want to know what works haha
The Ohm-rating on your cab should be equal to the Ohm-rating of the output jack it is connected to. You'll usually have either 4, 8 or 16 Ohms.
are all 4x12 cabinets 16 ohms and all 2x12 's 8ohms? is that how it works? :')
oh right haha cheers man
also; what's the difference in having one speaker cable leading from the amp to the cab and two? :S
The most common 4x12 of all, the Marshall 1960, is switchable between 4 and 16.
The only time you really see two cables going from head to cabinet is when using a stereo head. On the 1960 you can also run them as stereo. Two of the speakers are for left and two for the right.
Some 4x12's will have an extra socket so you can daisy chain a second cab. In that case you'd be running each cab at 16 ohm and the resultant impedance of the two cabs will be 8 ohm.
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Quote by TheQuailman
Are we talking about one head plugged into two different cabs?

i mean if i were to have 2 speaker leads coming out of my jsx into one single 4x12
what'd be the difference between having 2 or 1?
oh right haha awesome
well i did that at a show 2 nights ago when i played with liferuiner from canada so i hope i didnt damage their cab! D: haha
you wouldn't be damaging their cab. you would be damaging your amp.

you can run 2 cables out of your head into one cab, but you need to treat it as using two 212 cabs rather than one 412 cab and match impedance. So if you plugged into a typical Marshall 16 ohm cab in stereo for example you would need to set the amp to 4 ohms (each stereo side is an 8 ohm load). Otherwise you are putting a lot of extra stress on your power tubes.
Last edited by al112987 at May 12, 2011,