Is there a direct correlation between impedance and volume?
If I had two cabs with the same speakers, one in series, one parallel, would one be perceived as louder?
Also, how is an amp's performance affected by using a higher impedance cab than the amp calls for... such as an 8 ohm head into a 16 ohm cab?
nope, no correlation at all.

but, if you were using an 8 ohm cab and you had the 4 ohm option selected on the head, it would probably be more quiet. now, as far as that goes, i think you can do that safely if you wanted with SS amps, but a friend of mine told me that with tube amps, the ohms should match exactly to avoid damaging your stuff. you wouldnt want to run a 4 ohm load and have the 8 ohm option selected on the head. youd run the risk of damaging your amp.

7 String+ ERG Legion!!

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