Hi there,if you're reading 8.5 ohms on your meter (DC),then it's not an 8 ohm impeadance,it's most likely 16 ohms and your spkrs. are a little worn out.Normally a 16 ohm spkr.reads around 11 ohms DC and an 8 ohm spkr.reads around 5.6 ohms. Sounds like a 16 ohm cab with worn spkrs. to me. You might want to take the back off and check them out a little more. Good luck,Mel.