I think this gets into frequencies and roll-off points; stuff that I can never remember.
The E string on a bass (E1) is 41.20Hz; a low D (D1) is 36.71; and a low B (B0) on a six string bass is 30.87.
The lowest note on a piano is A0 at 27.5Hz
Supposedly, the lowest frequency humans can hear under normal conditions is 20Hz, which is between an E0 and an Eb0.
For the last 14 years, I've have a Polk Audio powered 12" subwoofer in my stereo system. I'm not sure which model it is, but a search suggests that the frequency range goes down to 30 or 32 Hz. However, Polk doesn't show where, and how fast, the low end of the frequency range starts rolling off; so that number really doesn't tell us much.
I can say that when I play back the recordings I've made on my bass, the low D's come through nicely.
I'm guessing (I'm no audiophile, nor do I know what I'm talking about with regard to good low end stereo response) (plus, I have significant hearing loss, including low end loss in my right ear) that you may want a subwoofer to add to your stereo that goes down to around 30 Hz before dropping off (say within 3db of the speaker's overall range).
But then, what was the music you were listening to with the "extremely low frequencies"? What instrument was producing the bass; and do you have an idea of what notes they were?
Another thing to look at; what is the frequency response of the speakers you currently have? And do the specs show within what db range (i.e. +/- 3db) that range is within?
I'm hoping some of the more learned audiophiles in our community will chime in, as I can never remember any of this technical stuff.