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Re: Any amps with tubes will have more distortion and will distort the frequency response

This is true, non linear distortion in tubes is at least an order of magnitude higher than for most solid state units, sometimes several orders of magnitude different. You will be very hard pressed to find a tube amplifier with less than 1% THD + IM at rated power while most well designed solid state amplifiers made after the mid 1960s have THD + IM of 1/2% or less even 0.1% and in some cases 0.01% and distortion decreases with reduced output. This being said, according to Dr. Bose, distortion under 6% is inaudible so even the worst tube amplifiers have inaudible non linear distortion until they are overloaded. The real distortion in tube amplifiers comes from those awful output transformers with their highly non-linear hysteresis and eddy current losses. It's important to remember that they are invariably used with very high output impedence circuits, the typical plate impedence of a tube being 6.5 kohms to 15 kohms which must be matched to 4 ohm and 8 ohm speakers. There is no reason why a low impedence OTL direct coupled vacuum tube power amplifier with enough output tubes and a very robust power supply couldn't equal the best ss units in bass performance and that is what I think we are talking about here. OTOH, the relatively high parasitic capacitance of a vacuum tube triodes (the reason we have tetrodes and pentodes in the first place) might cause some slight HF rolloff making it sound more mellow and therefore more like other typical tube amplifiers disguising the harsh high frequency sound of shrill loudspeakers and poorly recorded cds. IMO, most audible differences even among solid state amplifiers are due to minor differens in FR as they are used in real world operation, differences not apparant in bench testing with resistive loads. This can be easily corrected with equalization and is no justification to purchase a very expensive amplifier whose only advantage is a slightly different spectral balance. IMO, also, there is no such thing as "grainy" sound. The term "grainy" implies a fine discontinuity as in a grainy photograph which just doesn't exist in audio systems.

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