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The short answer is yes, you can replace a subwoofer. But it needs to be really close in pitch, wattage, impedance, etc. to the other speaker, or you will most probably be able to hear a difference in sound quality. Speakers are very simple to replace in most instances; the hardest part is locating a suitable match (even in size, screw hole alignment, etc.).
So my recommendation would most strongly be your other option. Do find the exact same subwoofer second-hand, or buy another set together. Reason being.... there are "crossovers" that send the appropriate frequencies to each set of speakers. So if you try to mix and match speakers, you might end up getting a crossover set "cutting out" a small frequency range.
The short answer is yes, you can replace a subwoofer. But it needs to be really close in pitch, wattage, impedance, etc. to the other speaker, or you will most probably be able to hear a difference in sound quality. Speakers are very simple to replace in most instances; the hardest part is locating a suitable match (even in size, screw hole alignment, etc.).
So my recommendation would most strongly be your other option. Do find the exact same subwoofer second-hand, or buy another set together. Reason being.... there are "crossovers" that send the appropriate frequencies to each set of speakers. So if you try to mix and match speakers, you might end up getting a crossover set "cutting out" a small frequency range.
