audphile here are reasons for purchasing a tube amplifier:
1 longevity: as the tubes are replaceable you can easily renew your amplifier.
2; easier to service then solid state a tube amplifier is a simple design and are easier to work on.
3: the sound is customizable by tube rolling
4: in general tube amplifiers produce a wider deeper soundstage then most solid state designs.
5: midrange liquidity most tube amplifiers produce a lusher more fleshed out midrange then most solid state designs.
Dave and Troy
Audio Intellect NJ
tube dealer