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Double down, good or bad?

I came across this article on Atma Sphere's website:

http://www.atma-sphere.com/papers/myth.html

In short, Atma Sphere believes having a power amp that is capable of doubling its power when impedance is half is not necessarily a good thing because speakers in general do not have a flat impedance across all freq range.

On paper, it does make sense. Though I am sure speaker designers take that into consideration and reduce/increase output where necessary to achieve the flatest freq response, that explains why most of the speakers measured by Stereophile or other magazines have near flat responses.

But what if designer use tube amps to design his speakers, mating them with solid state should yield higher bass output in general? Vice versa, tube amps yield less bass output at home?

I have always been a tube guy and learned to live with less bass weight/impact in exchange of better midrange/top end. Will one be better off buying the same exact amp the speakers were "voiced" with, not that it will guarantee good sound, at least not to everyone's ear.
semi
gregadd
574 posts
 
I always thought that doubling down was the sign of a technically correct amp that could handle the "WICKED LOADS" (without oscillating or otherwise becoming unstable) rather than a requirement.
I would never go so far to say it should be avoided. Ralph knows a lot about amps. By his own admission he pushes the technical envelope and is quite a design radical. His amps don't double down. I am sure he has had to explain that to a lot of potential cutomers.
swanny76109
382 posts
 
Read Nelson Pass's discussions-see passlabs.com. Nuff said.
atmasphere's avatar
atmasphere
11,760 posts
 
I'll take it a step further- there aren't **any** tube amps that double power, yet the tubes vs transistors debate has been here for 40 years... what does that tell you? The tubes failed to be the 'obsolete' technology that they were supposed to be- people keep listening to them.

The simple answer is that they must be doing something right!

The ability to double power as impedance is halved has been entirely a solid state thing. The idea behind it is that the amp is considered 'load impervious' if it can make constant voltage output into all loads, IOW double power as impedance is halved (conversely halve the power as impedance is doubled), so you can get flat frequency response from a speaker that has a box resonance. But what if the impedance curve of your speaker isn't based on a box resonance, like an ESL, magnetic planar or horn system? The model starts to fall apart.

So here's where that leads:

http://www.atma-sphere.com/papers/paradigm_paper2.htm

Its not really a tube vs transistor thing after all- its a bit bigger than that, just as it is not about objectivist vs subjectivist, and we are talking about equipment matching too. Its all those things, but also about the fact that the industry has a dilemma: make it look good on paper to make lots of dollars, or make it to sound good to the ear to make lots of good sound?

Its my contention that this has been going on a long time and the industry does not like to talk about it (doing so reveals the purely monetary angle), resulting in a ton of confusion (and often bad sound) in the audio community.
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