High powered amps for low sensitivity

I have a pair of speakers that are 3 way with raal ribbon tweeters

Several amps I have do not like the 84 db sensitivity or 4 own load at higher volumes and with dynamics

The speakers sound fabulous when not pushing the amps limits

I am running out of usuable volume in my system due to a .24 mv mc cartridge and the high demands

Looking for something very dynamic and natural sounding that can handle a hard load to drive these

You didn't say if you were looking for a tube or an SS amp.
It took me more than a few auditions and a while to find what I was looking for to drive my low sensitivity Totem Mani-2's (85db, 4 ohm), but eventually found contentment with, first, a Cary CAD-120S Mkii, and finally with a move to a pair of Rogue M-180 Monoblocks. Happy hunting.

Rogue Audio Medusa... try it!
You would probably like something from Ayre. Maybe a pair of V-5's or the mono's. Theta as well.
McCormack DNA 250, 500 or the 750 Mono's. I also like the Coda and Threshold amps. You can also easily find the Belles 350a that would be similar to the previously mentioned amps.

Personally, I use a Rowland M112 with my Evolution Acoustics MMMicoOnes that are 86db and 4 Ohm minimum.

Good Luck in your search!
This is a perverse quest.

High sensitivity/low power is the goods - do you have a friend who can let you hear such a rig - you may never go back...
Try Wyred 4 Sound, SX 1000 mono's or ST 1000. Good sound, very articulate sound that is as good as the source material that feeds it. Way lower priced than the performance might indicate. They are over 500 watts into 8 ohms, stable into 4ohms. I drive Vandy 2CE's with plenty in the tank with plenty of room to spare. I also have KEF LS-50 (85db) and still easily fill a room with beautiful sound. I haven't tried ribbons on them yet, but as long as they aren't too low of impedence(1 ohm) they could sound awesome. I have heard their equipment on Magnapans and they are among the most difficult to drive to louder levels. It was the smaller 3 piece system they just came out with on their smallest amp(100 watts a channel) and the sound was still very liquid and engaging. Good luck in your search.
Triode, I get where you're coming from... but not everyone needs to take the same path to musical audio bliss.

I feel both approaches can be valid so I'm not taking sides. Although you have a different preference, why discourage others from choosing another way?
Since you used "natural", have to answer Plinius. Dynamics without the dramatics.
If you running out of volume, I believe that your preamp does not have a sufficient gain for your cartridge.

What's a Rowland M112? I have a Rowland 112. Is that the same amp?

Yes, same amp. Should have read model 112. I love it!