Upgrade to Dedicated Preamp

I have a pair of Paradigm Studio 100v4 speakers, an older Parasound 2 Channel Power Amp, Marantz SA-8004 CD Player (net yet purchased) and a Yamaha RX-V2500 Receiver. I use the receiver as the preamp in the system. I am thinking of getting an older preamp for around $1,000 to replace the Yamaha. Would that be a noticable upgrade in my system?