Is there a list of full-range speakers (20-20kHz) somewhere on the internet?

Let me chime in here ,being 40 years in audio ,and owning a Audio store for almost 10 years.  There is No standard on true specifications , if for instance the speaker gets to 28 hz for a fraction of a second at 90 db  they will specify this .

playing bass to a constant  SPL is the hardest thing to do ,bass starts falling off fast 

you will not get a speaker That can do a honest 20khz to 20 hz  

continuous unless you have $$ deep pockets . Having no Set standards there are many ways to stretch the truth  . You want to see true graphs and waterfall plots 

for a sustained time ,but almost never due , plan on spending at least $30 k on up 

to companies you can trust.

Not one  of the chart mentioned above will do a true 20 hz in room or even close .

and please remember the higher the spl level even more less likely 

bass even at 25 hz which btw anything below 28 hz is low HZ vibration. Or rumble 

a concert grand piano is around maybe 28 hz , these low frequencies low off very fast and the spl is not sustained , in fact less then 4% of music at most is even recorded even  at 30 hz , if you can get bass at 30 hz thsts not rolled off steeply 

then Thst is very good . A high quality powered sub like the JL Audio Fathom line 

have great Bass room correction and will play mid to low 20 hz region 

Punch in the chest Bass .