I bought the S.E.X. amp for my headphones, but decided to build speakers for it. I bought a pair of Fostex 208E drivers on ebay, then a flat-pack of recommended enclosure, with T90A super tweeter. Am in the process of building right now, will let you know what they sound like in a week or so. They are large speakers, so it depends on your taste/size of room. I think the SEXy speakers on the Bottlehead website would be a good choice. Most sensitive speakers pre-built (non-DIY) cost $1000's. See Goodwin, Cain & Cain for example.