These are the fairly efficient speakers I am presently using with my Dumortier equipment. They are very smooth, excellent bass and a wonderful soundstage. They are great for jazz and classical music enthusists, but may not be ideal for heavy rock. Each speaker cabinet weights approximately 95lbs. Drivers were hand made 19 x 14″ cone, Chrome plated magnet, with 4 co-axial tweeters. Frequency Response was said to be 15Hz to slightly less than 20KHz, maximum power 50w, comprehensive off board x-over, mid-range and tweeter controls. Cabinet size is 3.5-4 cubic ft. Speakers were made in England and very few ever made it to the United States. Prior to using the 901’s, I had been using a very nice pair of Goodman Axiom 80 speakers that I also very much enjoy. I find the EMI’s a little more to my liking, though the Axiom 80’s are very hard to beat.