Tom Evans Audio Design pre-amps include:

The amps include two products, very different in design:

Tom Evans electronics contain phase error correction circuitry. To ‘get’ what they are really capable of you need a speaker that will show the spatial cues (because of this the ear / brain is able to make much more sense of what it is being fed, it sounds like more information gets in) needed to reproduce a real stereo picture in true perspective. So you can now see the importance of this speaker design to Tom Evans.