Hi Kevemaher!
Hate to tell you this, but loudspeakers are very imperfect devices, and frankly there has only been limited progress over the last fifty years. The field is mostly limited by materials science and the cone and dome materials we have to work with. Software synthesis has advanced crossover design since the crude efforts of the Sixties, but cone materials and magnet design are only a little better.
It’s a fact of life that dynamic compression is a problem with low efficiency loudspeakers, which why they are unsuitable for PA, concert, or movie theater use. Watts are nearly free these days, but a multi-kilowatt amplifier at home will do nothing more than destroy the loudspeaker. It comes down to voice coil temperature. Copper has a temperature coefficient, which means it gets less conductive as it gets hotter. Not only that, the heating/cooling cycle is quite slow, on the order of several seconds, much slower than the dynamics of the music being played.
So in practice, just throwing watts at the loudspeaker does not solve the problem of dynamics. If you really want 110 dB peak dynamics, you need more efficient speakers, not a kilowatt amplifier. But scaling down is a reasonable goal, say, maybe 95 dB peaks. With speakers that are 85 to 88 dB/meter/watt efficient (very typical real-world numbers for audiophile speakers) 60 to 100 real watts should be plenty, with any extra just there for headroom.
If you crave headroom, bigger amps are not the solution. Go ahead, try a 500-watt Class D amp and see if it sounds more dynamic. Maybe a little, but much less than you would expect. On the other hand, try a 95 to 100 dB efficient loudspeaker and you will be physically stunned at the headroom, and your craving for more power will disappear.
What’s going on is the more efficient speaker is throwing away less power in the voice coil for a given SPL level. Hot voice coils are very undesirable, and not just for reasons of reliability. There’s no good mechanism for active cooling, nothing like a tiny fan or anything like that. The heat radiates into the thermal mass of the magnet, which in turn gets hot, and that heat convects into the enclosed air of the cabinet. Don’t worry, there’s no risk of fire unless you feed that 500-watt amp with full power sine waves.
But ... if the speaker is four times as efficient (6 dB higher), guess what, there’s four times less heat radiated by the voice coil for the same SPL at the listening position. And the amp can be four times smaller too. However ... there’s no free lunch. The bass enclosure volume grows in direct proportion to the efficiency (if the F3 low-frequency cutoff is held constant). So efficient speakers are necessarily bigger, or have higher cutoffs in the bass region, or a combination of the two.
These is a long-winded way of saying don’t expect big dynamics from small speakers, no matter what the reviewers say. And 500-watt amplifiers don’t necessarily cure the problem, although you can certainly try and find out for yourself.
