Moving away from inefficient/low impedance speaker in order to move to a Tube Amp

I found a lot of the older speakers sound very good with 20 watts wpc. 

I've been running Macs and the last 4 years Carys with great success. I had one pair of 88db sensitivity @ 8 ohms speakers that used a quasi second order 4 way XO to help distribute the load. It was still a 6db first order bass section, with 2 12" drivers and a 12" passive radiator in a slot. That bass section hit 20 ohms. 

Guess what it pushed it like a champ by design. Amps like 20 ohms a whole lot better than 4 ohms. The weird thing is they sound really good to. Short heavy speaker ICs helped too. With a dampening of close to 100 @ 8 ohms. Not much between the amp and the driver (6db first order) but an inductor. The BIG 12" drivers are very well controlled with a Cary V12R and just 2 fat bottle 6L6 per channel. single ended at 20 watts or UL at 40. THEY ROCK. 95 db they are running out of gas.. LOL A MC275. That amp will run you out of the room.. Over 100db..

FR is full range or friggin' rummy take your pick.

That is Pope Mozartfan of the Wide Band. He really likes his speaker system..

Regards

My Omegas rock with very few watts. Worth a gander. 

I have no need for inefficient amps that double as room heaters. Try the fabulous AGD amps, they look like tubes, they sound like tubes, they drive any speaker. They consume less energy, save you money, tubes don’t wear out. They even glow orange! To me, the future.

I think it is a matter of finding the right speaker and then matching them with the proper amplification.  Even if the the speakers are supposedly not efficient enough to work well with lower-powered amps, I personally find that, in most instances they can be made to work with modestly powered tube amps.  I find that most people grossly over estimate the amount of power they need or try to achieve rock concert volume level even though the speakers and the room itself are ill-equipped for such practices.  Every choice is a set of compromises and I personally choose to go with very high quality at modest listening levels, and every improvement I make tends to make the sound enjoyable at lower, not higher, volume levels.

If you like the Harbeth speakers you have, I don't see how you can save money by getting another speaker of higher efficiency and then looking for a lower powered amp.  The really good sounding low powered amps are NOT cheaper just because they deliver lower power.  High power these days is cheap to achieve, quality at all levels of power is not. 

My local Harbeth dealer sells only tube amplifiers, and most of them, including the best sounding ones, are low powered.  The only Harbeth model that seems to benefit from higher power is the 40.2, and even they sounded their best with particularly good lower-powered amps (but played at decent, but not extremely loud levels).  

It has been said over and over on hundreds of posts. It is the old horse power vs torque argument in engines. Watts per channel is only a small factor in the overall power of an amp. You can buy an amp with 500 wats per channel that has no power and you can buy an amp with 5 watts per channel that has tons of power. Do the research and reach out to the companies to break down the amps total package and specs. In todays world you might even be able to contact the designer and ask them to define your solution.