I just noticed that the back plate of my AA270 silverface Bandmaster Reverb says "TOTAL LOAD 2 OHMS" at the speaker jack. All of the Bandmaster Reverb schematics (AA768, AA1069, AA270) say, "TOTAL LOAD 4 OHMS". I have always run this amp with a 4 ohm load. A 2 ohm output is normally for 4 eight ohm speakers in parallel but the Bandmaster Reverbs were supposed to push 2 eight ohm speakers in parallel. Is the 2 ohm plaque simply listing the amp's minimum load?