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Hey guys, i need some help, i need your advice on the SONY HT-DDW670, i just bought it last saturday but want to know if i can improve the sound, first:

1. Is it True that it will Sound better if i connect it directly to the Dvd player instead of the TV?

I connected this way:
- Audio cables from Home Theater to the TV (Red and White cables)
- Audio and Video cables from Dvd player to the TV (Red,White and Yellow Cables)
- and finally Audio and Video cables from my PS2 to the Tv (Red, White and Yellow cables)

Do someone please knows if i can improve something?

2. All my life i've been Cranking it up, Tv, stereo, guitar and car stereo so i don't know if i'm kind of Deaf or the Sony HT-DDW670 doesn't have enough power? or maybe i didn't connect it well enough, i will appreciate any advice or comment regarding this.

3. Is it wise to buy higher quality cables? does this improve something?