Why Don't We See More High Current Electronics?

03-16-11: Unsound
Tvad, I for one would hate to lose you, and your valued balanced contributions to this forum. This particular thread doesn't seem that contentious to me. I do hope you'll reconsider.

I strongly second these thoughts. Grant, as I indicated earlier I have nothing but the highest respect for your innumerable contributions to this forum, from which I and countless others have benefited greatly. I too very much hope that you will reconsider.

Best regards,
-- Al

Yes- audio equipment does not care what kind of music you play on it.

An amp with a low output impedance does not have a frequency response that varies with a speaker's impedance.

That depends on how the speaker is designed. Take a look at
http://www.atma-sphere.com/papers/paradigm_paper2.html

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Yeah, we've had this discussion before. Same old same old. Lots of assertions, but no supporting data. Negative feedback is bad because it causes time-domain distortion, distortions we can measure aren't important, and high output impedance doesn't really affect frequency response linearity. Frankly Atmasphere, your assertions remind me of Audioquest's argument that skin-effect really does matter at audio frequencies, even though all of the measurements say it's inconsequential.

I think it has been well-said previously in this thread that we don't see more high-current amps because they're very expensive to build, and because most people don't need anywhere near as much power as they think they do at low impedance levels, so very high current amps are mostly for people that have more money than sense (like me).

Tube amps are for people even more skewed towards money than sense. ;-)

Isn't clipping an even worse consequence than unbalanced frequency response alone?

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Yes, absolutely. But unless you listen at *very* high levels (like averaging higher than 95db) most audiophile amps (100w+ per channel) with most speakers (89db sensitivity at 2.83v) probably won't clip. If you are clipping there are lots of 200w+ amps into 8ohms that will likely do you or your speakers harm before they clip.

Actually, my experience is that most audiophile speakers sound like crap at very loud levels. There are notable exceptions like Legacys, big Wilsons, and the top-of-the-line Revels, to list a few, but most don't, so I'm wondering what people think they need so much power for? I know people think they need 600w/channel into 4 ohms, and if they're willing to pay for it I say: go for it, but the math looks like you'd be producing 120db+ peaks, and I can't believe people are listening at those levels. Or am I naive? :-)

"Actually, my experience is that most audiophile speakers sound like crap at very loud levels. There are notable exceptions like Legacys, big Wilsons, and the top-of-the-line Revels, to list a few, but most don't, so I'm wondering what people think they need so much power for? "

Add OHM Walsh (omni) speakers to the list of exceptions.

These shine at lifelike levels but also require the power and juice to do it best. Part of this is the Walsh driver and teh omni design that fills the room with sound more like a live acoustic performance rather than directing all its energy at you and making you want to leave the room, like speakers at a rock concert.

Most people who have owned the over the years run them off more commonplace amplification and probably have never likely heard what they are capable of. That included myself as well until recently.

My Dynaudio monitors do not mind the power and current, but can also get by better without it, though they will never deliver the meat on the bones at higher levels like a pair of large, robust suitably powered full rangers.

I think some people, especially those running ss amps, are comforted by the idea that there is nice margin of available power away from clipping. Others claim that some distortion is audible from stressed amps before full clipping occurs. Some times the extra power is not that much more expensive. Some amp manufactures claim that their Class AB amps slide from Class A to Class B at a ratio of power, e.g. 20% of rated ouput. Some amp manufactures claim that their Class A amps are only capable of sustaining full Class A output at their 8 Ohm rating, as the impedance drops so does the ability to maintain Class A output, e.g. at 4 Ohms those amps are only capable of producing half their typically rated output into 8 Ohms in Class A. If that's the case, the higher powered amp(s) might sustain higher quality sound further into power demands, though not quite up to full available power output.