I had a look at the specs for your amp and the Pioneer speakers. I also had a look at the Impedance curve for the Pioneers - http://img.canuckaudiomart.com/uploads/large/1449643-vintage-pioneer-tower-speakers-cs-959-made-in-j...In terms of power handling, your amp's 8-4 ohm specs show it struggles to double down in power to 4 ohms, however the CS-959's have a relatively high nominal impedance (6.3 ohms), 90db sensitivity, reflex loading, and more importantly, a fairly benine impedance curve. Hence despite being a 4-way speaker, I think your amp should be fine (unless you like to listen at very high SPLs).
As to how that pair would sound together, that's hard to say. You can only really know if a set of equipment has good synergy to your ears once you hear them propertly setup (preferably in a familiar room). I'm more of a high end guy, so hopefully someone familar with those speakers can chime in?
As to how that pair would sound together, that's hard to say. You can only really know if a set of equipment has good synergy to your ears once you hear them propertly setup (preferably in a familiar room). I'm more of a high end guy, so hopefully someone familar with those speakers can chime in?