Keep this in mind....Emerald Physics is ten year old design. And that was Clayton Shaws company. There have been no positive changes for ten years. In fact, after the sale of the company it looks like some of the components may have been changed to lower cost asian stuff. The latest lineup of product from Clayton's Spatial Audio is actually the third generation since he started Spatial. There is really no comparison between newest Spatials and the old lineup of Emerald. If you are going to the M series, I would suggest the Sapphires. I, myself, have the X5's and love them. The finest system I've had and I'm not a young man.