Watts and power


Can somebody break it down in layman's terms for me? Why is it that sometimes an amp that has a high watt rating (like, say, a lot of class D amps do) don't seem to always have the balls that much lower rated A or AB amps do? I have heard some people say, "It's not the watts, it's the power supply." Are they talking about big honkin' toroidal transformers? I know opinions vary on a speaker like, say, Magnepans - Maggies love power, right? A lot of people caution against using class D amps to drive them and then will turn around and say that a receiver like the Outlaw RR2160 (rated at 110 watts into 8 ohms) drives Maggies really well! I'm not really asking about differences between Class D, A, or AB so much as I am asking about how can you tell the POWER an amp has from the specs? 
128x128redstarwraith

And this one🤷‍♂️, well what can I say but, new/old product protection mode?

Looks like we'll never see an amp from him that can give hopefully give more than 50% wattage from 4ohms down to 2ohms especially the "old amps" the "new amp" when it released "may"??  if all the stars are lined up.

The classic statement from him was,  "Our OTLs do a nice job on the Wilson Alexia"
This is what that would look like (amp being the bulge).
  https://images.boredomfiles.com/wp-content/uploads/2018/04/14-woman-sleeps-with-python-731x457.jpeg
   
Cheers George  

I earned a living for my entire adult life as an electronics technician. I have a "First Class" radio telephone operators license. Most people today don't even know what that is, but once upon a time it meant something. I go back to a time when we used "slide rules". I mention all of this for a reason, one of them is the fact that I know formulas up the "ying yang".

For years I had a 150 watt per channel SS amp. Presently I have 70 watt tube monoblocks. I can't tell the difference in power. That's because neither of them went to school and don't even know "Ohms law"

Audio pertains to what you hear, while electronics pertains to formulas you work out on paper. I could hear those amps, but I never heard a single solitary formula.

Those amps and my ears told me that it takes 2 watts of SS power to equal 1 watt of tube power. Don't blame them, they never went to school.


It couldn't possibly have anything to do with amplifier architecture and pleasant soft-clipping. Nope, it couldn't possibly be that. It probably has nothing to do with the rated power at your speakers lowest impedance either.

2 watts of SS power to equal 1 watt of tube power


Instead of starting a new thread, I thought I would drop in a question on these same issues: I've been running a Nuforce STA200 with two 8ohm speakers, horn loaded, so the sound emerges with little effort and the amp runs cool. However, now I'm buying Tekton Moabs and they push a 4 ohm load. The Nuforce is stated to be suited to 8 ohms, not 4. The Moabs are efficient, running at a rated 
  • 98dB 2.83V@1m sensitivity
If the speakers run easy, what am I doing to my 8ohm amp, were I to hook them up...?
listening99,

Unfortunately, I could not find much in the way of testing of the STA200, and as you probably know, the marketing literature is very sparse w.r.t. details.  There is this test on AudioScience    https://www.audiosciencereview.com/forum/index.php?threads/review-and-measurements-of-nuforce-sta-20...
... which is all done into 4 ohms, and other than fairly high mains noise, nothing looks off. Since you have not mentioned an issue with your likely highly efficient horn loaded speakers, that does not appear to be a problem, but if the Tekton Moab's are a lot more efficient than what you have now, that could be a problem.

Take the comments made by the "reviewer", AMIRM, with a grain of salt. He is the type of "measurements" person, that gives other people who believe in measurements a bad name. His comment
"Looking at the power rating versus distortion, the STA-200 doesn't bring much to the party over the much cheaper Topping TP60 ($199)"
...  shows a lack of knowledge/experience w.r.t. what is important. At low power levels, where almost all music is, the STA200 has much lower THD than the Topping TP60, and considerably lower IMD. The STA200 though clips really hard w.r.t. IMD. With the really efficient speakers, hopefully you won't run into that issue.

Tekton is usually conservative in their impedance ratings. When they say 4 ohms, it usually will not dip much below 4 ohms. I would say you have little to worry about other than what is stated above.