Re: DSP units and questions regarding their use and my system
You don't need rear channel to use a DSP. In fact, rear fill is not desirable at all for a "proper" sound stage setup.
The typical goal with music reproduction is make the sound system disappear acoustically to the point that the sound you hear mimics that which you would hear in a live venue. Since in a live venue there are no musicians behind you, there is no need for speakers behind you. While it's true that there are sounds coming from behind, those sound are reflected off the back of the venue and are delayed naturally.
In the end, a well designed and setup front stage will provide you with all the rear fill necessary and adding anything to that will only serve to color the sound.
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