I have never listened to valve amplification and feel like I'm missing a 'whole new' world of hi fi. Everywhere I look the units are quite pricey. Icon Audio has a starter unit for about £600 but it's 15w x 15w. That to me seems very low but how does it work? is that enough power to drive my neats? are there any other valves amps that are cheaper so I can get the 'velvety' experience?