My reciever (Onkyo) doesn't have a dedicated Phono input. So does this mean I have to buy a preamp to hook my turntable into first? I saw a Sony Turntable that said it had a preamp built in. I have an old Pioneer turntable. Is there a way to tell if it has a preamp builtin? It's very old (over 15 years) so I'm assuming it doesn't. Thanks!