I'm building a set of GR Research A/V speakers for my parents, who will only be listening to classical and mellow music at normal levels. I need a good and cheap (oxymoron) sub to match up with them. Is this a job for the Dayton 10" powered sub, or is there another "value" sub out there that can get to 30hz clean and flat. Would I be doing the GR's a disservice by not running a higher quality sub? DIY is an option as well.