That can certainly be done, either with an adapter cable or with an RCA-to-XLR adapter. However I would advise against doing so, for at least two reasons.
First, your amp is specified as having input impedances of 50K unbalanced/1K balanced. 1K is an unusually low input impedance, and is almost certainly too low for your PL preamp to drive with good results.
Second, there are at least a few amps, such as certain ARC models, that will not work properly when their balanced inputs are provided with unbalanced signals. In those cases the power capability of the amp is greatly reduced, because half of the balanced signal path does not receive any signal. I don't know if that concern would apply to your Coda amp, but it is conceivable that it does.
Finally, even if those concerns weren't applicable, I would not expect there to be any sonic benefit from providing the amp's balanced inputs with unbalanced signals.
Regards,
-- Al