#1
Hi, not too long ago i bought a Peavey JSX 2x12 combo. However, it seems like it's not "insanely loud" like a lot of people claim a 120 watt guitar amp would be. When i bought it, the Ohm setting on the back was (and still is) set to 8 Ohms. Could this be the problem?

It has the stock JSX speakers, and they say they're rated at 8 Ohms each.

Thanks,
Pac Man
#2
Did you buy it new or used?

Two 8 ohm speakers wired in series = 16 ohms total. Probably how it is set up so run amp at 16 after verifying.

Two 8 ohm speakers wired in parallel = 4 ohm total. Less likely.

I'm guessing the power tubes are getting old and dying. I'd replace them.

The amp should be extremely loud after say 4/10 on the volume knob.
#3
If they are in series (16 ohm total), that would explain why you're losing volume, but its more likely the tubes as 311 said.
#4
Well they're connected to a single 1/4 inch cable that splits to connect both speakers to a single input which means they're in series, right?

It's still really loud, but i just wondered if changing the ohm setting to 16 would make it louder. I heard that setting the ohm switch too low can make it quieter than the amp would be otherwise, and can also push the output transformer.

I do want to change the tubes out, but i really can't afford $130 for the set of KT77's and 12AX7's i want at the moment.
Last edited by Pac_man0123 at Sep 5, 2010,
#5
Check the speakers, if its series the positive of one speaker and the negative of the other will be connected, and then the other of each speaker will be going to the jack. Dont turn it on again until you've checked, you could possibly damage the amp (although if the speakers load is higher than the output impedance its nowhere near as bad as the speakers load being lower, you'll put more stress on the OT but thats better than blowing it with a lower mismatch)
The issue would be with the power tubes if it was a tube problem, so you wont need to change the preamp tubes.
Last edited by littlephil at Sep 5, 2010,
#6
The speakers have 1 connection tab that's painted red and 1 that's bare metal... the red on one goes to the bare on the other, and the other 2 are connected to the wire that go to the amp's speaker output.. i'm assuming that's what you're talking about, and that means that the total impedance is 16 ohms, which is what i should set my amp to, right?

And i know i wouldn't necessarily need to change all the tubes, but i was just saying i want to change them all but i can't really afford it. For all i know, it has the stock tubes in it. I doubt it, but still.
#7
They're in series then, so the total impedance is 16 ohms. The amp should be set to 16.