Top of the line Sony ES speakers (made by the best technicians available to Sony in Germany) between 1994 and 1997. Spec’d at 4ohm/ 88.5dB, so they need some “juice” to give full enjoyment. IMHO -a decent quality amp of 100w+ would be ideal :) Think Carver, Parasound, Krell... perfect. A class D "Breeze Audio" TPA 3116 chip amp is another (and much cheaper) option. YMMV... These TOTL unicorn speakers were fully restored by Josh Dodd (Loudspeaker Repair Services) last month, so internally they are essentially “as new” and will likely need a minimum of 2 weeks running in to come on song… at 7.5kg per speaker, you just know Sony have built these with the best possible cabinets and internals available at the time (ES series perfection). Bid to own -a low reserve and sensible “Buy Now” means these won’t last long. To the best of my knowledge they are the only set available in the Southern Hemisphere -and none for sale (info. via the Hi-Fi Shark website) have been serviced/ restored. An absolutely stunning piece of mid-1990’s audio engineering by Sony… the SS-B40 ES. Check my 100% selling feedback and bid (or Buy it Now) with full confidence -cheers John (thestereoguy)