I have a Sharp Micro Component System (Model XL-MP131) and am wanting to add a subwoofer to it. On the back of the system there is an RCA jack labeled "Subwoofer pre-out" and in the manual it says "When a commercially available speaker with a built-in amplifier is connected to this unit, you can enjoy sound with emphasized bass. Connect an RCA cord from a commercially available speaker with a built-in amplifier to the SUBWOOFER PRE-OUT jack"
Is a speaker...
A: A powered subwoofer is really just a single, larger, speaker with a crossover to limit it to low frequencies and a built in mono amp. The output from the jack on your speaker system provides a low level signal that requires an external amplifier.
Given the speakers on your system are not top of the line there is little point adding an expensive subwoofer (you can spend $thousands on top end models) ... maybe Sharp sells a suitable accessory model,
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