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Big John · 08-21-2008, 10:57 AM

Do not plug the 8 ohm cab into the 8ohm output on the amp and the 16 cab into the 16 simultaneously. You will damage the output tranny. Those outputs jacks are wired to taps coming off the tranny's windings, and are meant to be "either/or" and not "both at the same time".

Paralleling an 8 ohm cab with a 16 ohm yeilds 5.33 ohms. Since you don't have a 4 ohm output jack on the back of your amp, this mis-matching of cabs isn't a good idea. However, since you have two 16 ohm cabs, you can plug each one into the 8 ohm output and you're good to go.

When there's two jacks on the back of an amp for a certain ohm rating, that means that the total impedance of both jack must equal that number. So, one cab at 8 ohms gets plugged into one 8 ohm jack. Two 16 ohm cabs get plugged into both 8 ohm jacks because the total ohms is 8.

08-21-2008, 10:57 AM	#2 (permalink)
Big John ...with a big mouth Join Date: Mar 2007 Location: NW Posts: 2,145 Thanks: 1 Thanked 18 Times in 8 Posts	Re: Ohms.... Do not plug the 8 ohm cab into the 8ohm output on the amp and the 16 cab into the 16 simultaneously. You will damage the output tranny. Those outputs jacks are wired to taps coming off the tranny's windings, and are meant to be "either/or" and not "both at the same time". Paralleling an 8 ohm cab with a 16 ohm yeilds 5.33 ohms. Since you don't have a 4 ohm output jack on the back of your amp, this mis-matching of cabs isn't a good idea. However, since you have two 16 ohm cabs, you can plug each one into the 8 ohm output and you're good to go. When there's two jacks on the back of an amp for a certain ohm rating, that means that the total impedance of both jack must equal that number. So, one cab at 8 ohms gets plugged into one 8 ohm jack. Two 16 ohm cabs get plugged into both 8 ohm jacks because the total ohms is 8.