First off, power is only important if you need it. Meaning, that if you are using speakers with a sensitivity of 105db, you could run them with a transisitor table top radio. You would only need about 500 milliwatts, half of a watt. But if you have maggie 3.6, or Sound lab, then you need a few hundred watts, like 500wpc into a 4ohm load. The load presented by the speaker is important, and the sensitivity also is impoprtant. Finally, they need to be synergestic, less concrete, but very real. I like well matched SS and well matched tubes. A friend has the latest legacy whisper speakers rated at about 96db sensitive, and we compared a 70wpc vs a 600wpc SS amp. Which had the best bass??? The tube amp, best mids, tube amp, best treble...you guessed, tubes. This SS amp is said to be a great match for the legacy whisper, but tubes beat it. All tubes won't as my quickies were a bit slow on these speakers. they are great with mine, 3.6's. Factors like damping factor, speaker sensitivity need to be included in the consideration of amplification. I prefer tubes, but cheap good watts are also available with SS.Jallen