If you already have a Blu-ray or DVD player, you don't need to buy a home-theater-in-a-box (HTIB) with a disc player built-in. These systems are called "Blu-ray/DVD-ready" because they include everything you need for a home theater, except for a disc player and TV.
Blu-ray/DVD-ready HTIBs are often geared more toward enthusiasts willing to deal with a full-size AV receiver and speaker package, in exchange for a more powerful home theater experience. These systems also tend to have more HDMI connectivity than HTIBs with built-in disc players, making it easier to integrate your existing home theater components. While true separates-based systems still generally sound better, the best of these systems are nearly as good and offer "all-in-one-box" simplicity.
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