As has been said, you need a volume control in the circuit, which is what a preamp does. Otherwise it would simply play at full volume all the time. Plus you must have a phono preamp, either built in to the system preamp, or a separate unit. The phono signal is very low output, plus it is equalized with an RIAA curve, and sounds horrible without the proper re-equalization.
Does your Scott integrated have pre-amp output jacks on the back? If it doesnt, you cant add a separate power amp to it.
Does your Scott integrated have pre-amp output jacks on the back? If it doesnt, you cant add a separate power amp to it.