Perplexed on how single driver speakers can cover such a large Hz range

+1 as usual to Atmasphere for an eloquent explanation.

@kokakolia, with respect, I think you are conflating/confusing perceived loudness and frequency range. A speaker with limited frequency range will often be perceived to be louder than a full range speaker especially if it's frequency response is ragged. A downside of speakers with limited bass response is that they are often driven harder in an attempt to get some bass impact, which then results in them being played too loud and showing up deficiencies elsewhere in the speaker.

It is the reason why the best headphone and the only one i like is a Hybrid with a dynamic cell specialized in bass and a electrostatic cell specialized in higher frequencies over 4,000 hertz the cross over slowly decreasing point for the two cells..And a grid of Helmholtz tuned resonators inside to clean bass and mid bass... it work so much well that none of my past 9 headphones compared one second to the K340... All are under my bed for eternity or for computer use... 😊

The AKG K340 can make a soundfield more defined and clearer than my speakers because of what atmasphere explained so well...

My room dedicated acoustic so well it was tuned , was limited by my Mission Cyrus speakers under 50 hertz...And their tweeter limitation and roll off..

When i lost my dedicated room i was sad... When i optimized this headphone i enter in sonic heaven anew but with no more too much acoustic limitations... A well optimized modified AKG K340 rival any headphone today... It is the only successful  hybrid headphone where one of the cell is not only a super tweeter as the dharma was..

Any designer in audio is an artist not only a scientist... because he must work and jugg with many trade-off at the same times... The designers who are not artist are not the great one , they apply a recipe...

As dynamiclinearity mentioned, at any given, whatever any driver is doing at any given time is a complex combination of many different frequencies albeit in a more limited way in a classic woofer, midrange or tweeter than a single driver design. It’s always amazing to me that this can occur & sound realistic. 
 

Even more amazing to me is that a single stylus in a phono cartridge can somehow do a similar but inverse thing &  react to the full range squiggles in a spinning vinyl disc & do so accurately!  Also similarly but not always true, the better cartridges can’t “ play loudly” either & general their outputs  are very low & require substantial amplification to be “heard”.  Thomas Edison was one smart dude!! 

@dlcockrum 

How?

@kokakolia 

You are obviously comparing single driver speakers to lower end multi driver speakers. Do you feel the same when comparing them to higher end speakers ?