Balanced Low Power Tube Monoblocks?

Ralph -- Thanks very much for your good response, with which I am in complete agreement.

But please note that my post (the one dated Sept. 8) was not dealing with tube amplifiers, or with amplifiers or speakers designed based on the power paradigm. It was addressing the narrow situation in which a speaker having a low impedance in the bass (e.g., 4 ohms), and a higher impedance in the mids and treble (e.g. 8 ohms), is being driven by an amplifier (typically a solid state amplifier) having an output impedance which is negligibly small in relation to the speaker impedance at any frequency.

And the question was whether or not such an amplifier driving such a speaker would produce an excessively bright response as a consequence of the amplifier not being able to double power into 4 ohms (relative to 8 ohms). And my contention is that it will not, as long as the volume levels are such that the amplifier is not called upon to deliver more current than it is capable of (and as long as the amp does not produce an excessively bright sound for other reasons).

Best,
-- Al

Shop around for a used Rocket-88R.

Thanks for the suggestions, Al.

Almarg- OK, I see your point, but in practice such an amplifier will in fact 'produce an excessively bright response' not due to frequency response variation but due to generation of odd-ordered harmonics.

I apologize for repeating myself often, but the simple fact is that that audio industry is ignoring 45 years of research into how humans perceive sound! Were that research taken into account, I would agree that your statement is correct as today's amplifiers would be different. What amazes me about all this is how the audio industry has stuck steadfastly to design rules that, even while they were being implemented during the 1960s, were already being proven wrong by said research.

What I am talking about is the typical amplifier that you are describing violates the most fundamental rule of how we perceive volume, by exaggerating odd-ordered harmonics. Another way of putting this is that you can be convinced that a sound is a lot louder than it really is if the 5th, 7th and 9th harmonics are tampered with. These harmonics are not only cues to the human ear brain system, they also contribute to brightness- quite literally our ears are more sensitive to these harmonics than they are even to vocal frequencies! So there is almost no way an amplifier like that will not appear to have excessive highs.

This is the fundamental reason why tubes are still around after being declared 'obsolete'...

Excellent points, Ralph, and I think we are now fully converged on this. Thanks!

I would add, though, in relation to the particular issue I raised initially, that a "voltage paradigm" amplifier with very low output impedance that is capable of doubling power into 4 ohms (relative to the power it can deliver into 8 ohms) would not NECESSARILY be either better or worse with respect to odd-order harmonic generation than another voltage paradigm amplifier with similarly low output impedance that is not capable of doubling power into 4 ohms.

Best regards,
-- Al