It is highly, HIGHLY doubtful that the receiver in a low cost HTiB is going to be anywhere near capable of directly driving any decent sub like the JLs (one, let alone two). Note that you have to read the fine print on the output of the HTiB, as they can be misleading and rated at PEAK power, not RMS, with the RMS being much, much lower. If it has a sub out, you could feed that to a separate amp to drive the JLs, but trying to run them off a HTiB receiver is asking for trouble.