Onkyo RF-X7

Hello guys. I have an amplifier Onkyo RF-X7. It is a two channel amplifier with a subwoofer pre out. I just want to ask what type of subwoofer will work with it. Do I need an amplified subwoofer or without amplifier? The problem is that I am short on money. Here in my country, once you buy a woofer then we cannot send it back. I don’t want to waste my money. So please I need serious answer.
Thanks a lot in advance
Note: You can check the pics by model name “Onkyo RF-X7”
Asked Feb 27, 2014

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