In summary, you can use either an RCA cable or a subwoofer cable to connect a subwoofer to your sound system. I recommend investing in a subwoofer cable if you want the richest, fullest sound from your subwoofer. If you're fine with sacrificing some sound quality for affordability, an RCA cable will do the job just fine.
With that said, let's take a closer look at the difference between a subwoofer cable and an RCA cable, their pros and cons, and how to choose between the two.
What is a Subwoofer?
A subwoofer is a speaker that reproduces lower frequencies - around 20 to 200 Hz - that surround sound, or two-channel systems can’t normally reproduce on their own. Subwoofers can deliver extremely low-frequency sounds like bass guitars, kick drums, and movie sound effects (e.g., explosions). The result is that you actually feel the audio, immersing you in the thump of a bass drum or the rumble of an earthquake.
In order to connect the subwoofer to your sound system, you have the option of using an RCA cable or a subwoofer cable.
What is an RCA Cable?
RCA cables are one of the most common types of audio cables since most home entertainment systems use RCA connectors for various purposes. An RCA cable has three plugs extending from one end in its most common form. These are color-coded (e.g., red, white, and black) to match the corresponding jacks on your TV or another audio/video component, such as a subwoofer.
What is a Subwoofer Cable?
Subwoofer cables are basically the longer and more powerful versions of RCA cables. They have thicker insulating material and more shielding to protect them from interference and noise, which can degrade your audio quality. They also use heavier-gauge wire to prevent power loss.
Which One Is Better?
Technically, both RCA and subwoofer cables can deliver audio from your sound system to the subwoofer. But what's the best choice if you're looking for the absolute best performance?
RCA Cables
Pros
The main advantage of using a regular RCA cable is that it's relatively cheap and easy to find. If you're connecting a TV or another audio/video component to the subwoofer, an RCA cable is likely what you already have. And if not, it's easy enough to find at your local electronics store or online.
It is also easy to use an RCA cable to connect a subwoofer - you can simply plug it in.
Cons
The main disadvantage of using an RCA cable is that it doesn’t deliver enough power to the subwoofer for demanding applications. This is because it can’t handle the relatively large amounts of power needed for subwoofers. Even worse, low-frequency sounds can become distorted by an RCA cable.
Subwoofer Cables
Pros
Because subwoofer cables are more durable, they can deliver more power to your subwoofer for high-volume applications and higher-quality sound. The heavy-duty insulation and shielding also reduce the amount of distortion to produce a more accurate reproduction of the audio.
Cons
A subwoofer cable is generally more expensive than the standard RCA cable. So it may not be a practical choice if you're just looking for a simple connection.
Can I use an RCA cable for my subwoofer?
As long as your RCA cable has the appropriate connectors, you can connect it to the subwoofer. To manage your expectations, though, an RCA cable won't deliver the same level of performance as a subwoofer cable, especially when it comes to bass reproduction.
Conclusion
RCA and subwoofer cables are two of the most common options for connecting a subwoofer to a sound system. Each has its pros and cons, and which one you choose will depend on what you want out of your speaker.
An RCA cable is convenient, cheap, and does the job - but an RCA cable won't deliver nearly the same power and performance as a subwoofer cable. Therefore, audiophiles, sound purists, and anyone who demands the best sound output from their speakers will find that a subwoofer cable is worth the investment.