Double down, good or bad?

Peterayer, The drivability has to do with whether the driving amplifier is based on Power theory or Voltage Theory, and which approach the speaker designer used.

Power Theory (or Power Paradigm) is where the amp seeks to make constant power into all loads. It will not succeed, but that is the goal. The Dynaco ST-70 is a good example, 4,8,16 ohms its 35 watts. Our own MA-2 is another, 4,8,16 ohm 220 watts. Some transistor amps fall into this category.

Voltage Theory (or Voltage Paradigm) is where the amp seeks to make constant voltage into all loads. It will not succeed, but that is the goal. Such an amplifier doubles power as the load is cut in half. Lots of transistor amplifiers do this but only a handful of tube amps do.

The speaker designer may have used an amplifier for reference. If so the speaker obeys the same rules that the amp does. So if the designer favors a tube amp, his speaker will likely follow the Power Theory. An example is Wilson Audio. If the designer used a speaker design program or favors a transistor amplifier, the speaker will be a Voltage Paradigm device. An example is the mbl 101E.

Anytime one kind of amp is used with the other kind of speaker, a tonal anomaly will result due to inappropriate power response. Here are some examples:
*Transistor amp on ESL =>bright high end, weak bass
*transistor amp on horn =>shrill high end
*tube amp with mbl101 => harsh midrange
*tube amp with B&W 802 =>weak bass

I have used the term 'Paradigm' in the past as those who operate within a paradigm seek to describe that which is outside that paradigm as wrong, on account of a restructuring of that individual's world view that the individual is understandably reluctant to do. It is easier for such individuals to see the alternative as wrong, but in so doing does not change the nature of reality.

This reluctance to accept reality has resulted in several debates in the audio world that are on-going and have been so for decades: tube vs transistor, subjectivist vs objectivist and the equipment matching conversation which you have asked about.

To deny the existence of the Power Paradigm denies the validity of ESLs, horns, magnetic planars, full-range drivers and a variety of acoustic suspension and bass reflex designs, as well as many tube amplifiers. The Power Paradigm places a high value on design responsiveness to human hearing/perceptual issues.

To deny the existence of the Voltage Paradigm is nearly impossible- that is what is seen in bench measurements from all magazines. Many acoustic suspension and bass reflex designs use the Voltage Paradigm rule. The Voltage Paradigm places a high value on design responsiveness to bench specification, particularly low distortion.

I side with the idea that audio equipment should obey human hearing/perceptual rules, as I maintain that human hearing is the most important aspect of audio. I get very little argument for the latter, but a lot of resistance to the former!

Ralph,Thank you for that explanation. I agree with your assertion that human hearing is the most important aspect of audio. I have found lately, that the speaker/room relationship or room acoustics may be the second.

I have not thought of or previously read about the "Power Paradigm" vs. the "Voltage Paradigm". It is interesting to view it from the speaker designer's point of view. I used to drive my Eggleston speakers with a Pass XA160 which had constant power to all loads, but I now use the Pass XA100.5 which doubles down as impedance is halved. The speaker's nominal load is 6 ohms, which means that the amps have about the same power. The latter combination sounds much better to me. From your explanation, am I to understand that the XA160 follows the "Power Paradigm" while the XA100.5 follows the "Voltage Paradigm" and that Eggleston probably designed the speaker with the latter in mind? It must sound better to me because the amp is better able to handle the load of the speaker. Or is it also because this paradigm places more value on low distortion, and that sounds better to me? This sounds overly simplified. Pardon me for my ignorance, but I'm interested and would like to better understand the issue. I'm fairly new to the hobby and don't have the technical background. Thanks.

Ralph just thinking off the top of my head.Because most speakers report "nominal" impedance and thier real impedance curve is all over the place, a doubling down amp would create serious spectral balance problems.
Looking at a frequency versus impedance curve like my Martin Logan CLS the high frequencies(2 ohms) would be driven 800 watts where the Low frequencies (8ohms) would be driven at 200 watts. Intuitively this would seem to cause spectral balance problems.
Does this make any sense?