Bass is less and less directional as it goes down in frequency. For best sonic integration, locating your subwoofer between your front speakers or beside one of them and close to the back wall will usually provide the best bass performance. If this location is not possible your subwoofer may be placed anywhere in the room without affecting the stereo image of your front speakers or the soundstage of your multichannel speaker system.
Corner placement provides the most bass, but sometime at the expensive of accuracy. (Fig. 1a)
A subwoofer placed near a wall usually provides a good balance of quality and accuracy. (Fig. 1b)
The Advantages of Using Two Subwoofers in your Listening Room
What’s the only thing better than a single sub? Two of them (or more)! Although a single sub can often provide enough bass for an environment, the quality of bass can be further improved with the use of two subwoofers.
Subwoofers are designed to play low frequencies and the frequencies that they play are comparable in size to your room which results in the sound waves bouncing off of surfaces and back on themselves cancelling themselves out. The more subwoofers we have, the more even the frequency response will be across all subs together. Placing one in the front and of the room and the other in the rear of the room (Fig. 2) usually provides the best bass performance and sonic integration.