Rower30 is right, most of the Dydaudio speakers I've heard have tight punchy bass but do not extend to the nether nether regions. A simple audition may not reveal this issue. Sometimes you have to live with equipment for awhile before these things become apparent.
In all honesty, I don't know if I'd worry about extension unless it's really bothering you. I went from a speaker with breathtakingly punchy bass ( Revel F50's ) to Revel Salons, and even though the Salons are far superior I still very much miss that quick punchy bass. So I guess it's a bit of a trade off, if you want speakers that extend down near 20Hz your going to lose somewhere.
In all honesty, I don't know if I'd worry about extension unless it's really bothering you. I went from a speaker with breathtakingly punchy bass ( Revel F50's ) to Revel Salons, and even though the Salons are far superior I still very much miss that quick punchy bass. So I guess it's a bit of a trade off, if you want speakers that extend down near 20Hz your going to lose somewhere.