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? 
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Showing 3 responses by millercarbon

Can somebody break it down in layman's terms for me?


Among the many wonderful quotes attributed to the late Nobel Laureate extraordinaire Richard Feynman is this one: "If you can't explain it to a six year old that means you don't really understand it."

Probably not an exact quote. Another variant goes, "I couldn't reduce it to the freshman level. That means we really don't understand it."

The common thread being the idea that when you really do understand something you are able to explain it in very clear and simple language and even to people with no special knowledge of the subject. 

Can somebody break it down in layman's terms for me?


Apparently not. Draw your own conclusions.
Can somebody break it down in layman's terms for me?


And so one after another all he gets is a bunch of technical info. When the answer in layman's terms is actually in this case absolutely identical to the answer in technical terms: THERE IS NO ANSWER IN TECHNICAL TERMS!

Every single one of the supposed answers above, most of which sound sensible, a few of which maybe even are, nevertheless are easily proven to be nonsense. All these things are at best factors. But remember- correlation is not causation!

What happens, and OP it will really help if you can learn this one early, is someone hears an amp that sounds unusually powerful compared to its watt rating. So they look for reasons. Perfectly natural thing to do, look for reasons. Let's say they find the amp is capable of delivering a lot of current. Wow that must be the reason! Unfortunately, sorry, BS, which is demonstrated as easily as listening to another low current amp that seems to sound just as powerful, if not even more so.

The same can be done for every single one of the other technical reasons listed above, and a whole lot more we haven't yet gotten around to. Not to worry, the people incapable of noticing the request for layman's terms are equally incapable of putting a damper on their need to show off with word salad. Er, technobabble. Er I mean technical knowledge.

Oh and by the way, you can go through and replace "power" and watts with just about anything you want- liquid vs etched, 3D vs flat, dynamic vs damped, any and all of it. Sometimes there's really good causes you can point to. When faster diodes are swapped and the sound improves its fairly easy to point to the speed and recovery of the diode. Although even then its wrong to say the speed is the reason- because there are even faster diodes that sound worse, and maybe even slower ones that sound better.

Now take that one part, the lowly diode, multiply it by a thousand for all the parts in a component. Then multiply that by a hundred for all the different circuit topologies (the way the circuits are physically laid out) then multiply that by a handful more for the way the chassis and, well you get the idea. Or at least I hope you do. There's just way more variables involved than you can ever hope to understand, let alone boil down to one simple number. To then point to that number and say, "THIS is why!" Is simplistic and shortsided in the extreme.


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?


Long story short, you can't. Its not only Class A, etc, but even among amps within the same class. The McCormack DNA amps for example have greater apparent power than a lot of other SS amps that test the same or higher. Its widely known that "tube watts are greater than solid state watts" simply because virtually all tube amps seem subjectively to have the power of SS amps rated twice as much. Even within tube amps there are plenty of 30 watt amps that seem as or more powerful than 60 watt tube amps- even though they may be running the same tubes!

Just a few of the many reasons why watts are one of the least important specs in all of audio.