That should work fine. Powered subs typically present a very high impedance (meaning a negligible load) at their speaker-level inputs, so it will not draw significant power from your amp.
For that reason, also, you don't necessarily need to use as heavy a wire gauge to connect the sub as to connect the main speakers.
BTW, connecting both the sub and the main speakers to the same pair of output terminals on the amp (A or B) should work equally well, although using A+B is most likely physically more convenient.
Regards,
-- Al
For that reason, also, you don't necessarily need to use as heavy a wire gauge to connect the sub as to connect the main speakers.
BTW, connecting both the sub and the main speakers to the same pair of output terminals on the amp (A or B) should work equally well, although using A+B is most likely physically more convenient.
Regards,
-- Al