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indhomecinema.com
THX
No home theater trend is more misunderstood than THX. THX is a seal of approval for equipment and software, but not a particular decoding algorithm like Dolby Digital or DTS. There are detailed technical specifications applied to equipment or software in order for it to be THX certified. When you buy a THX certified piece of equipment, you are guarenteeing that this piece of equipment meets the THX standards. Here's an example of the specifications:
Speaker to subwoofer crossover frequency set to 80hz
Reequalization of higher frequencies to lower their output for a smoother sound
Equal high power for all five main amplified channels
Subwoofers able to properly handle low frequency effects
Diffused dipolar surround channels
Low equipment noise
It is important to realize that there are many pieces of high quality equipment that do not meet THX standards. For example, the Skywalker ranch sound studio uses non-THX certified B&W 802 speakers to monitor THX certified recordings. THX certification is not something that one should require when purchasing equipment. Because of the high cost, I do not recommend the purchase of THX certified equipment.
Recently, Lucasfilm created a new lower standard for equipment known as THX-select and renamed the original standard to THX Ultra. The only difference between the two specs is the size of the room
