It's a sealed design and has the same frequency response as the Empire, 20-200hz +/- 3.5dbs. In an anecohic chamber most sealed designs dropoff gradually from about 50hz @ 12db/octave. That's one of the reasons, it's got such good midbass response. Anyway, the Legend, in room, will play like the Empire with less output. Most folks, with an Empire, are getting a flatish response to at least 20hz, some to 15hz. It's room dependent. As GranteedEV said, it will depend largely on your room size. If smallish, you should get a similar response to an Empire though with 6dbs less output. In a large room, with little or no room gain your < 30hz response is anyone's guess. It will be there, but will it be useable? It's a nice sub. 2 of them. colocated, are about equal to an Empire and will smooth out the bass response, though if you separate them, them Empire will still have more output.