The Sierra amps will work with your BAT source. The amps input impedance is 100Kohms using the RCA inputs(single-ended). The 100k can drive any load. The amps impedance is low (2200ohms) when using the XLR (balanced) inputs only.If you use RCA's for your interconnects, then the amp will be a excellent match.
Regards,
KWP
Regards,
KWP