A/B Switch or Mixer?

[gillsev]

I think I'm just gonna keep my old Dual 701 instead of giving it away at Ebay. It is still in top notch shape anyway. But now, I have 2 turntables with only one phono input on my receiver.

Should I get a switch selector box, or a mixer? If I decide for a mixer, doesn't it degrade the phono signal fom its purest form?

Thanks!