Tube microphonics, generally, degrade soundstage imaging and detail. As to an "identifying" sound, tubes do not have a sonic character - the sound is a product of its environment (circuitry). Bias, gain, plate voltages, feedback loops, etc., will identify the sound a tube gives you in a particular unit while external elements such as vibration degrade the presentation.
As to the "tube sound" (warmth, LF bloat, etc), it's attibuted mostly to distortion that's inherent in its construction and function as a gain device, especially at the clipping point. I also think that the microphonic characteristics of tubes contribute to the effect, so I'll take Sugarbries' side on this one.
As to the "tube sound" (warmth, LF bloat, etc), it's attibuted mostly to distortion that's inherent in its construction and function as a gain device, especially at the clipping point. I also think that the microphonic characteristics of tubes contribute to the effect, so I'll take Sugarbries' side on this one.