Why Don't We See More High Current Electronics?


It seems that in looking around for amplifiers and integrated amps that double their power as the impedance is halved (high current), they seem to be in a minority. Is it just more costly to build good-sounding high current electronics and the market demand for them just isn't there, or what?
foster_9
Well, Tvad, since I assume I'm the root of your urge to leave, I think you're over-reacting. For one thing, in the interest of full disclosure, I was multitasking when I typed in that response, and while (I think) everything I said was correct I actually *misread* your post in my haste! Yes, IMO, you still have a misunderstanding about ss amps work, but I'm actually feeling pretty stupid at the moment for explaining some behavior related to what you were talking about, not the specific effect you were actually describing! Sigh.

I also admit to enjoying banter like this entirely too much, and it was never intention to chase you (or anyone else) away. So how about you stay, and I'll try to cool my responses a bit, and I'll also try to improve my focus before I type!
Oh yeah, and a correction of my multitasking math, assuming a speaker with 89db sensitivity at 2.83v, and assuming a 4 ohm impedance, 600w/ch does not give you clip-free 120db+ peaks, you'd get about only 114db peaks or so.

Boy I'm stupid today.
Why would I want less power? I think the better question is why would I accept less. My reasons:

1. Even 110db peaks are really, really loud. I'd like to hear for a lifetime.
2. Most audiophile speakers will have significant distortion at these volume levels. Why listen to so much distortion?
3. Most stereo solid state amps will need well over 20amps at 120v from the wall power outlet to produce 600w/ch. What are you plugging the amp into? ;-)
Irv, thank you for offering the words of reconciliation to Grant.
03-16-11: Irvrobinson
For a good voltage-source amp with 100w into 8ohms, if the speaker has a peak impedance of 16 ohms into 4KHz the amp will clip at 50w, and if the lowest impedance occurs at 40Hz with 4ohms the amp will clip at 200w, but the frequency response at 50W will still be flat (within the amp's spec) across the entire spectrum up to 50w.

Trick question - what happens if the speaker is reproducing 4KHz and 40Hz *at the same time*?
Well, since one frequency is far higher than the other, there will be instants of time at which their peak amplitudes will simply sum together. If both frequency components have the same amplitude (which is highly unlikely with music), the amp could provide half of its maximum output voltage at each frequency, without clipping. Since for a given impedance power is proportional to volts squared, power delivery at each frequency at the clipping point would be 1/4 of the numbers you cited above: 12.5W at 4kHz, and 50W at 40Hz.

At least, I think so :-)

Regards,
-- Al