Hi. I also have a Nad T763 and the PSB Synchronicity One speakers. Recently upgraded to the Quad II Classic Integrated Amplifier(http://www.quad-hifi.co.uk/model.php?sector_id=3&range_id=7&model_id=48#)and it sounds fantastic.
The 763 is ok, but the Quad is from another planet. If you get a tube amp you will sell your 763 the next day....

I also recomend the NAD C 565BEE CD Player(http://nadelectronics.com/products/cd-players/C-565BEE-CD-Player)which is (much) better than other cd players costing 5 times more. This player can read cd´s at 44 khz and has Wolfson 24/192 dual DACs.