so my amp head has thingy that says "120w at 4 ohm"

and the back of my cab has a pluggin that says 4 ohm

but it also has one that says 16 ohm, and when i plug it into there it only uses the 2 right speakers.

can anyone explain to me what is going on?

I would think (4) speakers at 16 ohms would be 4 ohms (2) 16 ohm speakers would be 8 ohms and one speaker at 16 ohms?

It depends on how they are wired parallel or series.

that was super confusing, its an epiphone triggerman cab.

and its no wheres near as loud as i expected,

right now were running vocals through a fender 120w combo amp with 2 speakers, and i can hear that just fine even with my amp cranked, i know they are both 120w but, youd think the big ass cab would be louder. needless to say im dissapointed.

Chris, you've got to understand that running your amp at improper ohms can cause some unwanted results (as you described), but it's also really bad for your amp.

I've found that wattage isn't always an indicator of 'loudness'.
I've got 15 watt Class A tube amp that I run at 8 ohms with a pair of 12" Celestions - it smokes almost anything as far as 'loudness' goes. 15 watts, dude. I'd venture to guess it would smoke that combo your using for vocals (not to talk down).

The thing that's happening with your 16 ohm jack... that's your cab trying not to let the amp cook itself. If I had a dollar for every guitarist who blew an amp because they didn't understand ohm-age... well I could buy you a pizza. Bottom line - keep 'em matched. Make sure your amp and speaker cab are set up to use the same resistance (ohms).

Good Luck!

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