I don't think anyone has an A/V receiver that has enough current to drive typical 4 ohm subs. In the $500 price range, a lot of them that are rated at 100 watts per channel, will only drive one or two speakers at 8 ohms for the 100 watts. Some even drop down to under 10 watts a channels if all 5 or 7 are driven at once into 8 ohms. Maybe that's another reason for the point one sub output. I think the best option is a powered sub, or a separate amp that can drive your sub. This is an example of how receivers ratings are getting. Nothing like the hi-end we're used to. Link [http://www.hometheater.com/content/sherwood-rd-7503-av-receiver-ht-labs-measures]