A reader asked me how he could hook up a subwoofer to a typical stereo receiver. He liked his two main speakers just fine but felt like adding some more low end sound. He also wondered which one to buy.
There's two ways to hook up a subwoofer to a stereo receiver. Unlike surround receivers which have a dedicated line level subwoofer RCA type output, there's no such thing on a stereo receiver. There are other line level RCA outputs suck as a record out.
You could take a stereo RCA patch cord out of the record out and then use a Y cord to combine the left and right channels into one which then plugs into the subwoofer. The problem with this is now you have two volumes to adjust all the time. Ramping up the volume on the receiver with have no effect on the subwoofer. You'll have to adjust that volume from the subwoofer level knob on it. It does allow you to adjust the sub level differently for various types of music which you may find useful, more bass for hip hop, less for classical, etc. Still, it's kind of a hassle having to always be adjusting two levels.
The other solution is to use a subwoofer that has speaker level inputs and outputs. This was common amongst subwoofer at one time. In fact, some subwoofers were non-amplifed (called passive) and only had speaker level ins and outs. There aren't too many subwoofers which still have the speaker level option, but here's an entry level one that fits the bill nicely, Polk Audio PSW-111.
Simply run your speaker wires from the receiver to the subwoofer. Then run speaker wires out of the subwoofer to the main left and right speakers. Now the sub volume and the left and right speaker volume will be controlled by the volume knob on the receiver. You'll just need to adjust the hertz level at which you want to send sound to the speakers. This is called the roll-off and it changes according to the room environment and type of main speakers. You'll want to do some critical listening to find what's perfect for you.
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