How much power do I need? Find out using this method...


I've been hanging out on diyaudio and ran across this simple technique to measure the power used by your speakers.  So many discussions here revolve around this question that I thought I'd post the method...

If you have a multi meter, you can use the test tone & technique provided here to calculate how many watts your speakers actually use: https://www.diyaudio.com/forums/multi-way/204857-test-voltage-power-speakers.html

It’s super informative & useful: all you do is set your volume at the max listening level you use, then play the -12db 120hz test tone while measuring voltage at the speaker terminals. Square that value and you’ve got the maximum watts needed. Plenty to read at the link...
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Hi elevick. You have solved the problem by having very efficient loudspeakers and with your Mac you should have no problem making your ears bleed as long as the speakers can perform at those volume levels. Many if not most can't. But I have no experience with your speakers. The problem for most people running those levels is that either the amp is clipping transients or the speaker is distorting. 
I was responding to gs5556's comment about differences in perceived volume levels. To any listener a 1 dB increase in sound pressure is obvious, 3 dB is a rather large increase and 6 dB is a huge increase. If I were to increase the volume 6 dB on one speaker only the other one would literally disappear. Try it. There is another issue with point source speakers. They way the cast an image makes them sound surreal at loud volumes. It is like having the volume of the 6th row back in the 20th row.
Line source or linear arrays solve this problem by casting a much larger image so the volume and the row match up. 
In no way do I listen to all music at 95 dB. Also remember that the rating of your speaker is at 1 meter. I listen at the volume the music at hand sound right. There is a rare record that I will listen to at 100 dB like the Dead's Infra Red Roses. What fun to blow peoples brains with that one. If you want to know how your system and house deal with very low frequency transients get that disc. It is a selection of drum solos. Every recording has a "right" volume level depending on the type of music and the way it was mastered. I miss spoke. Some recordings have no right volume level usually because they are mastered poorly. As an example I was listening to Paul Simon's Graceland last night. The instruments are way out in front of his voice like he is standing in the next room over. So either the band is too loud or his voice is too far away. I love the music but it could have been mastered better or at least more realistically. Most people think this is a great recording. Waiting For Columbus is an excellent job all around. Turn it up and the band is right there everything in perspective. It was probably mastered off the sound board. For studio recordings check out The Smiths, The Queen is Dead. Great job! Waltz for Debbie I listen to at 90 dB. These are peaks by the way, peak volume measured with a dB meter. My preamp measures volume in dB but that has nothing to do with absolute sound pressure levels. dB is a relative term.
Sorry, but I never use a sound pressure meter while listening.  I have listened to the Dead drum solos many times...but never "sober".
I wish I could hear a 1db difference.  All I know is my work system is only 10 watts but with 95 db single driver speakers...
Maybe I'll try a sound pressure meter at work, not while tripping :-)
Note that "Columbus" had overdubs, and now I have to get my Graceland album out as I remember it being a well recorded thing...hmmm....
Quite a few live recordings have overdubs as all kinds of stuff happens. A pickup fails or a mic started distorting etc. A good mastering engineer can put an overdub in perspective. Frank Zappa was famous for this. Let me know what you think of Graceland. I listen on a line source system and the perspective might be different on a point source which is what most studios use for monitoring. I don't think so as it is usually just a change in sound stage not the relative position of the instruments.
The way Graceland was mastered originally (has it been remastered?) it sounds as if the engineer wanted to make sure you could hear every detail of every instrument so he moved them all up front. The detail is attractive but a bit surreal. If he had moved Paul's voice up front he would have been way to loud.