Well, i will answer these questions the best i can off the top of my head. I sell these TVs for a living so i have an idea. Anyhoo, yes the contrast ratio of the 530 series IS 20,000:1 while the 550 series is 30,000:1. That is the CORRECT number. Both sets have the matte finish. Only the 650 and 750 series have the gloss finish at the moment however rumor at my store is that a 630 series is coming out, not sure if its gloss or matte. The 530 has touch sensitive controls on the front while thee 550 series has buttons on the side. Im not sure why this is the case since the 550 series is technically a higher rated series. As far as i know the speakers on both series of TVs are 10 watts x2. As far as your question about the 71 series my answer is this...The 71 series had the gloss finish, 120hz auto-motion, 20,000:1 contrast ratio and i believe an 8ms response time. The 530 and 550 both lack the 120hz auto-motion but have a 5ms response time and 20,000 and 30,000 respectively. The 71 series did produce a lot of artifacts while the 120hz feature was active however. If you want 120hz get a 650 series. If you do not want it i would recommend the 550 series. Or if your patient wait for the rumored 630 series which combines the best of both worlds. If it were me and i wanted a TV right NOW i would get the 550 series. In fact i did and i own the ln40a550 and love it. If it were me and i was patient i would get the 630 series later. I wouldn't buy the 71 series at this point since the 650 and soon 630 series will be out. And i wouldn't buy the 530 series because the price difference isn't huge between 530 and 550. By the way dont pay more that 1249.99 for a Ln40a550 or more than 1399.99 for a LN46a550. Pay those prices or less. I have seen them that low or lower. I hope this helps.
I have been debating and reasearching on which model to buy in Samsung's 5 series model LCD TV's for a month. I have been waiting for the review from CNET to know avail. I know that the dynamic contrast ratio in the 550 is 30,000:1 vs. 530 20,000:1 (i got this from samsung's website so I 'm guessing this is correct) but is there any other deferences in these TV's??? Differnet websites have posted that the 530 has a dynamic contrast ratio of 12,000:1, 20,000:1, and 30,000:1 which one is it??? Does these TV sets have the glossy or matte screen (I perfer the glossy screen myself)??? Do they have the same processors??? Are the speackers the same??? I have read that the 530 has better speakers. Are this two models better than last years 71 series???? CNET community please HELP!!!

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