Unsound - power specs for amps are developed under static conditions. Music, however, is dynamic and that is where the difference between SS and tubes becomes evident. In my experience, tube amps deliver more dynamic power and hence sound more powerful in practical music listening than SS at comparable static power specs. This has been a consistent observation over many years and many different ss and tubed amps. Of course there are MANY factors that affect the resulting sound (like power supply, distortion profile of ss vs. tubes, etc) but for sheer dynamic power, tubes seem better to me.