i was wondering since i have a reciever (pioneer deh1950) with only 1 set of pre-outs, and i want to hook up a 4 channel amp with 2 sets of pre-outs, 1 being a sub pre-out, how would i go about doing this?

i hope someone can give me some advice on it since i'm stuck on my current hu (matagal pa bago mag-upgrade ulit ).

thanks!