Hi guys I just grabbed a good deal on this baby YBA-200 - she's in great nic. Sounds sweet as.. especially thru a 15" or mutiples thereof. On the rear it has an IMPEDANCE SELECT switch with "8ohms" & "4 ohms" & 2 spkr out jacks... In the manual it states (I don't have it here with me-but...) something like- Use the 4 ohm select if load is 2 ohms or 4 ohms?!?!?? Does anyone know IF it IS safe to run this head at 2 ohms??