In this addition of Hi-Fi Talk I will show you how to add an easy surround circuit to your existing two-channel system. Forget DTS, AC3, SACD, DVD-A, BFD, etc, etc…..this will give you true ambience channels for your music listening.
For this project you'll need two additional speakers (they can be just some small book shelf type), some quality speaker cable (enough to reach from your main amp to the rear of your listening position) and a quality 25 ohm 2-watt potentiometer. Please see wiring diagram below...
Once set up, use the pot to turn down the sound of the surround speakers until they just seam to disappear as a source of sound. You should find that even though they are not audible, the sound field will seem to collapse when they are disconnected. You may want to add a switch to the scheme so as to be able to turn the surrounds on/off. Also make sure that your amplifier can handle the load of the additional speakers being hooked up in parallel- check with the manufacturer. This set up should work well for music as well as for decoding Dolby surround from movie sound tracks in a video system. You will have to experiment with the rear speaker placement and the pot setting. Also, if the rear speakers seem too bright you can add some form of mechanical tweeter attenuation -- maybe some cloth over the tweeter.
Have fun with this one. It does work well if set up properly.