It’s been years since I’ve dabbled into the receiver world. First question is what pros does a preamp provide? \ni just upgraded my old Denon 3805 and bought the new Denon 3700. The old receiver was a powerhouse in watts and sound, but was outdated with the lack of HDMI and all the tech that comes with it. Would it makes sense to use my old receiver as a pre amp? And can I?