im using a 200 watt randall head with a 300 randall watt cab. when i output the amp at 8ohms and connect to the cabs 16 ohm input, i have a wonderful, sufficient, metal amp. when i output the amp at 4 ohms and input it into the cabs 4 ohm input the amp is about twice as loud but cuts out when i play low chugging palm muting. its not a speaker pop, the speakers can take it, the cab stops making sound. if i run the 4ohm output into the 16ohm input its identical to the 8ohm output in sound and volume.
when i was first looking for a cab, i thought my head was broken. it does this on other cabs too. its too bad because it is a loud amp but it seems to be hiding its other testicle in the 4 ohm output.
thanks to anyone who will educate me. i dont have the cab specifics but i can find them.