This is a good question... bass extension is influenced by a LOT of factors... room placement being most important.

If a speaker were to be placed on a post 100' in the air, it would be radiating bass into all space, 360 degrees around, but up and down, too. The higher frequencies are more directional, beamed, so we are just talking low bass here.

If the same speaker were to be placed against a wall, say outside the 10th floor of a high rise, not on the ground, it is radiating into half space. So, the same energy is concentrated into a smaller area.

If that speaker is place on a floor, against a wall, it is radiating into 1/4 space. That same energy is concentrated even more. And compared to the higher frequencies it reproduces, the bass is stronger yet, by 6 db.

If the speaker is placed on the floor, in a corner, it is now radiating into 1/8 space, so the bass will sound even stronger.

The height of the woofer, or port, from the floor, whether the floor is carpeted or not, and other room conditions will greatly influence the amount of bass heard.

So, I take all bass figures as suggestions of what might be, rather than fact.

More important, is the bass "quick"? Does the speaker accurately reproduce the bass, or does it ring? Is the bass boomy and sustained? Does the bass drum go "BOP!!!" or "Wooooooom...". Does string bass sound realistic or is it just low? This is where a good 15" speaker will outshine a small "subwoofer".

Technopop and other synthesized music is not a good choice for auditioning speakers. You don't know what the original synthesized sounds were supposed to sound like. I like to use something with live orchestra, see how that sounds... Holst's Planets is good, especially Mars. Put on a jazz combo, piano, bass, drums, etc. Listen to those instruments. Is it convincing? Close your eyes. Is the combo right in front of you, sounds live? If a speaker system will do this, its a winner.