Tube vs Tran

Dave, I respectfully disagree. The idea of damping factor is mostly mythology. If you hear a differece between an amp with a 'damping factor' of 1000 and one with 50, its likely due to other things than 'damping factor'. More likely the differences you hear are due to the amounts of negative feedback required to make a 'damping factor' that high.

One would be severely challenged to actually be able to define a sonic artifact and point to 'damping factor' as its cause. Audio signals require that the power energizing the speaker diaphragm not only carry it to the limit of the signal's excursion, but also back again to zero. There are no audio signals that stop at the peak of the waveform and fall to zero instantaneously- even synthesizers don't do that.

This is not to say that the output impedance of the amplifier does not have an effect on the sound (damping factor is an expression of output impedance, BTW). For more on that see
http://www.atma-sphere.com/papers/paradigm_paper2.html

Tube amplifiers can have excellent bass (given an appropriate load). The 'wooly' term at best is innuendo without a being a true statement of merit. There are tube amplifiers that can reproduce a 20Hz squarewave as well as transistor amps can. In the past there were older, lessor designs, but that says nothing about what is possible today.

Thanks all for a lot of great information. I AM NOT going to use a sub and have never really liked the idea or cared for sub in TWO channel system. With proper speaker, I don't think it is needed.
Rick

Here's a link about damping factors:

See http://en.wikipedia.org/wiki/Damping_factor

Measured square waves are not relevant to damping because of the interaction of the speaker and cable is also part of the equation.

Dave

I agree that damping factor has some effect on the poor bass of most tube amps. But wooly bass can mostly attributed to the hundeds of feet of wire in the output transformer. This is not always the case but the main reason.

03-26-08: Rwwear said:
"I agree that damping factor has some effect on the poor bass of most tube amps. But wooly bass can mostly attributed to the hundeds of feet of wire in the output transformer. This is not always the case but the main reason."

"Wooly bass" isn't just a tube vs. SS thing. Last week I heard a Primare integrated driving the DALI Helicon 400Mk.2 sounding unacceptably wooly. It came under control when we put in a Rowland Capri/102 combination, but it really started to shine when the Rowland 501 monoblocks were switched in.

I think it's a combination of damping factor and watts. You can have a relatively high damping factor, but if it's combined with low wattage and big drivers in the speakers, then it can still get "wooly."

Bi-amping a big speaker is a great way to get control of the woofer(s) while optimizing the "liquidity" of the mids and treble. You can combine high watts and damping on the bottom, separate the signals so they don't muddy each other and free yourself to maximize the euphonic character of the mids and highs with tubes.

Dave