How many watts do you really need?

Alll else being equal, more power in reserve is better.  The problem is that all else is never equal and big, high power amps do not sound the same as high quality low-powered amplifiers.  For my taste, I prefer certain low-power tube amps over any other kinds of amps.  This works quite well with high efficiency speakers; for less efficient speakers there are more compromises.  This is the nature of all gear selection—one picks priorities and acceptable compromises in any choice made.  For my somewhat efficient system (99 db/w), I run amps that output 5 watts per channel.  This does not leave me with much reserves of power but these amps work well with the vast majority of music I play at the volume levels I normally listen.

Many of the best woofers for use with high efficiency horn systems are large in diameter, but with very light and nimble paper cones.  They are designed to have stiff, low excursion suspension/surrounds.  Such woofers blend well with the very fast midrange compression drivers.  But, again, compromises have to be made, and it is usually the case that such woofers cannot go very low.  Some of my favorite horn systems employ 18” woofers that are good to 35 hz.  I’ve heard others good to about 30 hz that employ 22” snd 31.5” cones.  
 

regarding low bass, I posted this in the 'warm' discussion, I expected some reaction

"I went for extended bass when younger, but I came to think that was not so important, and in fact, I think what I and other people like most about my speakers is related to ’not too much bass’. (they are 15" huge magnets, weigh 37 lbs each,16 ohm highly efficient, bass is not lacking, just not further extended).

As I have said many times, Bass can be directional, i.e. Stereo Bass, always consider the overtones, and when there is less low room filling mono bass, and all the omni-directional reflections of that, everyone remarks on how the imaging of Jazz bass players and the sounds of bass decay are wonderful. Can less bass produce ’warmer’ bass? Not frequency emphasized, but a purposeful lack of extension, again, more apparent, not frequency emphasized.

Certainly well executed extended low bass is amazing, but mostly large spaces, larger than mine."

Of course, a side benefit of 'that's enough' is that greater power for extended bass is not needed.

@parkergetdean 

I have a Fisher 500C Receiver ready to sell. I’m between NYC and Philadelphia, so I think I will make it local pickup, demo before buy. It’s noise free, checked and FM aligned by VAS Audio.

So, I just ordered one of these units with meters and two amp switching and two speakers switching, to set the 500C up and compare to my main system, easy demo, and get my friends to help me determine if it alters my main system by being in-line.

30 day returns, $150. not much reason not to try it.

https://www.amazon.com/Fosi-Audio-Amplifier-Visualizer-Component/dp/B0CZRMSHJB/ref=sr_1_7?sr=8-7

If I keep it, or before I return it, I may move it from system to system, make a few notes, I’m interested to see what my office system, AR-2ax 90db sensitivity are needing from my Little Luxman SQ-N150 10 wpc tube amp. Notice, the center of the meter is 2.0 watts.

SQ-N150 has small Decibel meters, I’ll see if/how they compare.

Oh yeah, my Yamaha CR-1040 Receiver in my Garage/Shop system has small meters, I forgot. Also driving AR-2ax speakers.

This will explain everything you need to know about how many watts you need.  Hi Fi Shop Sketch - complete version

It certainly does. Thanks for the clarification!