I'm in the process of upgrading my sound system and I'm interested in getting a reasonably high-end headphone amp. I just upgraded my amp to an Ayre AX-7e and my turntable to a Rega P3-24 with a Graham Slee Reflex phono stage all running through Klipsch RF-82 speakers. I have a pair of Sennheiser HD650 headphones but I need to get a headphone amp for them. Can anyone recommend one that would be suitable for my setup. Many thanks for any suggestions.