Can I hook a phone up thru a rca cable to a subwoofer

Solution
You could connect the phone to the subwoofer speaker level inputs but the subwoofer only has an amp for itself so your phone would have to be able to driver the left and right satellites. It won't have enough power to do that so you would need a stereo amp to drive them.
No. You could not do that. You need an amplifier in order to listen to your phone over speakers. Your phone outputs what? Somewhere between 2 and 10 watts? That amplifier is looking for something closer to 475 watts. Some receivers/amplifiers do have smart phone connections.

-Wolf sends
 

TJ Hooker

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Apr 15, 2014
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That sub has an AC power connection to draw power from. It's feasible it could take an audio input from something like a phone.