I’m putting together a temporary display with a ‘monster’. It will only make very deep grumbling noises, so I really only need a sub. From what I can see, most subwoofers seem to have an rca connection. What’s the simplest way I can connect an MP3 player to an active subwoofer without destroying it?
You will need a standard 3.5mm stereo mini plug to 2 RCA plug cable. If the sub only has a single RCA input then use either of the 2 RCA plugs. Assuming that the noises are mono it won't matter which. Start with the mp3 player volume and sub volume at 50%. Bring the subwoofer level up first. If you can't get it loud enough then bring the mp3 level up. If the mp3 level is too high you will get some distortion due to overloading the input of the sub. May actually sound better with the distortion in this case but you could damage the sub.