I know two dealers from two different areas who both found that Primare(from Norway, I think) equipment really opens up the 804s. I thought this was significant because Primare is relatively new and unknown on the scene here in the US, yet both these dealers stumbled onto the same conclusion after trying lots of other stuff. Might be hard to find, but a very good value and built like a brick craphouse, and it looks great too. Best of luck.
Tim
Tim