Can you use just one side of a MESA Stereo Power Amp?
Any Boogie power amp can be used in mono by connecting the input signal and speaker to one side only of the amplifier. When running this way, the input of the side not in use should not be connected or damage may occur. As with any tube amplifier, a load of some sort must be connected if there is signal at the input. Always make sure to connect the speaker to the appropriate side receiving the input signal, and make sure the speakers are connected to the matching impedance jack on the amp. As an extra precaution, the volume of the side not in use should be turned all the way down and the presence control turned all the way up. We also advise plugging a shorting jack in the speaker out of the unused side (take a 1/4" mono plug, make a connection from tip to sleeve within the jack) to prevent any possibility of motor boating from occurring.
All current production Boogie power amps are not bridgeable, but can safely be used in mono under the above conditions. We suggest alternating sides that will be used in mono applications to provide even tube wear from side A to Side B.