Be aware that if you are using a stereo source (two channels, red/white), you can butter it up all you want, but you are not getting surround sound. The closest you can physically get to true non-stereo sound with a stereo source is using Dolby Pro-Logic and Pro-Logic II. But to achieve that, you need a Dolby Pro-Logic/II receiver which would cost a pretty penny. This clearly does not do this.
What this adapter does, is the same thing you would achieve by splicing the rear left, front left, and center speaker wire together and connecting it to a single-channel plug (a white RCA plug). Then the same thing being repeated for the right channel with front right, rear right, and center.
Using this adapter, the sound will be all around you, but it won't be surround sound. You won't hear space ships and laser blasts flying around you, you won't hear dialog coming directly from the TV, music from the left and right, and special effects from behind you, nor will you hear any of the other advantages of a real surround sound system. It recreates two really big stereo speakers. That is all. You will hear one set of sounds on the left speakers, and another set of sounds on the right speakers. The same sound that is in your FRONT left speaker will be coming out of your REAR left speaker. Your center speaker just outputs the sound from both front left and front right speaker. The exact same thing can be accomplished by just running a speaker wire from your left speaker to another speaker behind you. What you will hear is two distinctive channels (left and right), but duplicated and sent to the back speakers. Actual 5.1 surround consists of 6 individual channels, one per speaker, plus the subwoofer.
This device does not allow 5.1 surround sound. If you buy an expensive 5.1 speaker set, you are selling yourself short.
Now if you don't care about this and you are just trying to utilize your 5.1 setup on a stereo source, by all means, the product works great. But if you are trying to avoid buying an AV receiver, you will be strongly disappointed.