HDMI cable made a difference in picture quality??

I just bought an a 42 inch LG LCD flat screen TV which is has full HD function. I have a HD cable box and opted to use RCA cables betwwen the box and TV. I am getting missed opinions from the cable provider and the LG dealer about the usefulness of the HDMI cable hookup. Does it actually improve picture quality??? If so,how much? and will it also improve non-HD programming??? I have seen several adds from Monster Cable and Audioquest touting their HDMI cables. Monster has one that is about $70; another is about $100. I have seen even higher price tags from Audioquest. All comments welcomed. Thanks Jim
I am getting missed opinions from the cable provider and the LG dealer about the usefulness of the HDMI cable hookup. Does it actually improve picture quality???

Some people and members of this site will say that using HDMI improved the picture quality and some will say that they saw no difference . Try both ways for a few days and see which way you like best.

and will it also improve non-HD programming???

Meaning the digital channels or the analog channels ?
HDMI cables were designed to transmit digital signals, both audio and video. I would use HDMI cable if you want to take advantage of your 1080p TV. HDMI cable does make a difference especially if you have bigger TV.

I compared a generic brand ($45) to a Monster Cable Ultra 1000 ($120). The Monster is better in sharpness and color saturation. Lately I switched to Kimber Cable's HD29 which is slightly better than the Monster but costs more.
I tried both connections and really did see a marked improvement with the HDMI connection on my 50" plasma. You can get very high quality HDMI cables from Firefold or Monoprice for very little cost.

I actually A/Bed the $7.00 Firefold HDMI cable to a $100 Monster Cable HDMI and preferred the Firefold.
I would stay away from Monster Cable for anything [ I was a dealer years ago. ] The Monoprice is very good for the money, I would get one. It is MUCH better than generic cable and you may never want anything else. I used them for a while, I now use Wireless World Silver on mine and when I became a VDH dealer got one of theirs for my wife's set. Both are excellent but pricy. Try the Monoprice first, the law of diminishing returns applies here,
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"I actually A/Bed the $7.00 Firefold HDMI cable to a $100 Monster Cable HDMI and preferred the Firefold"

I'd better try the Firefold then. A $7 is better than a $100? Well, I agree price alone doesn't mean much sometimes. I am gonna order one and report back. If that beats my Kimber, I will sell the Kimber and get some Blue Ray discs. Thanks for the suggestion.
Agreed, I use the $7 ones from partsexpress. A hdmi cable is a HDMI cable.
Yes, HDMI is better. Monoprice is the way to go. Difference in HDMI cables, only if they are defective, meaning they do not meet the HDMI spec. The IEEE rules on what the spec is. If the manufacturer brands his cable 'HDMI' they are claiming it meets spec. Recently the IEEE did a sampling of some cables and did find about 15% of those tested were defective, not meeting spec. So differences are often related to a defective product.
HDMI looks much better to me than component video. But, I have not been able to tell the difference between HDMI cables. The inexpensive ones I bought from Fry's look/sound as good as the Audioquest one the I bought to test.
as to your question of hdmi and standard def pics, the real differnce is that most home theater receivers and universal players will only upscale those pics through the hdmi for compliance issues. big differnce in quality.
Riley804, Regarding the non-HD channels, I guess I mean the analog channels like Ovation, American Life Network. Ovation offers interesting music and visual arts programming. ALN offers reruns of Hill Street Blues, St. Elsewhere and Mission Impossible. Elsewhere and Blues look fair to poor; also some digital non HD channels seem slightly out of focus. LG makes a very good TV, so I don't suspect a problem with it. Though, my cable provider often announces it has transmission problems; I live in a high rise apartment building which offers cable hookup which probably further degrades the signal. If I move the TV to the other side of the room, I will be able to take advantage of my Audio Prism power line conditioner which I also use for the stereo system. That might help. I look forward to your answer. Thanks Jim
HDMI has it all over component on my video system. I bought Belden cable from Blue Jeans. The picture is ultra crisp, the color well balanced, and brilliant. The detail fools my cat into thinking those are real birds flying around during Sunrise Earth. She will watch the 80 inch screen for the full hour.
The power conditioner to TV and cable box will make a difference. I would also upgrade the power cords for both the TV and the cable box. PS Audio makes a nice power cable for the small connector often used in video and not too expensive. HDMI the way to go for facility and upscaling SD but, I don't think there should be much of a difference in HD with very good component cables (the ones that come with a cable box are usually not too good) and HDMI.
Below is a copy of what I posted here on 8/20/2009 http://forum.audiogon.com/cgi-bin/fr.pl?fcabl&1250622275&openmine&zzNasaman&4&5#Nasaman

- Nordost Silver Screen: 8 (very bright, clean and details. Low noise). Highly recommend for High-end users.

- AQ hdmi-3:............ 8 (very deep, beautiful, and accurate colors. Great details & very low noise). Highly recommend for hi-end users.

- AQ hdmi-1:............ 7.5 (colorful, details, and low noise) Recommend for Hi-end users.

- Supra Cable v1.3:..... 7 (bright, clean, & details. Low noise & decent price). Good for Hi-end users.

- BlueJeanCable:........ 5 (decent colors, somewhat noisy & lack of sharpness. Great price.) Decent for Hi-end users.

- Monster-1000:......... 4.5 (its video quality is, somewhat, equally to BJC)I wouldn't buy it.

- MonoPrice:............ 2 (very dark, nasty, & inaccurate colors. Lots of video noise; it's a VCR's picture quality) Not recommend for Hi-end users.
The Wegrzyn's pure 4N solid silver HDMI cable is the best HDMI cable that I have ever tried. You can see fine details in the HD picture that were missing with other HDMI cables that I have compared them with!..
Once again, I have seen no noticable difference in HDMI cable output with the different cables I have tried.

It could be those seeing a difference are using some of those "Magic" power cables too, that "open up the soundstage, and reveal the inner detail".

Once again, spend your money on components that make an improvement in sound/picture, not on crazy cables.
And there you go.Cant go wrong hereabouts,cheers,Bob
I am really fasinated by the responses I have seen here. Some members claim to see sharper or brighter pictures. Can somebody explain to me how is it possible with digital? I mean, how can cables transmitting digital information apply filter to make picture less or more sharp, or darker or brighter?
I am really fasinated by the responses I have seen here. Some members claim to see sharper or brighter pictures. Can somebody explain to me how is it possible with digital? I mean, how can cables transmitting digital information apply filter to make picture less or more sharp, or darker or brighter?
You've got me! And I would ask those who claim to have seen significant differences between good quality, presumably spec-compliant hdmi cables if they went back and forth between the cables being compared multiple times, to verify that their observations were consistent. And if they made the comparisons using identical program material; identical cable channels if the cable box was the source; identical lighting conditions; and identical warmup conditions of the tv set.

-- Al
i'm with macdad, almarg et.al.--i can't see a whit of difference between the generic hdmi cables eforcity sells for 22 cents on amazon and the megabuck super-duper, 48 carat gold, handmade by aryan-demigods cables peddled which retailers peddle so mercilessly. either the cable carries the signal or it doesn't--don't believe the hype.
No difference in picture quality yet the sound from high quality Gold HDMI connectors ($200+), OMG, I bet it would be like night and day for most people here!! LOL

Blind Audiophile with Nipper "his master's voice".
The only way to really test two HDMI cables to see what cable is really better is to freeze frame the HD picture and then compare the two cables looking at the same still picture. Then you can clearly see fine details missing in that still picture and faded looking colors too when you compare Wegrzyn's pure solid silver HDMI cable to other HDMI cables on the market.....
If you freeze frame, it would cause the digital source to output the exact same data per each frame per second. So if there is distortion caused by cable not up to specification, radom noise would be introduced in the form of digital artifacts. They would be so obvious as they would not look like as if there is a digital filter applied to the picture to make it look faded or details missing. Plus, since the data is constant, any artifact would not appear still, as the data stream is constant, any noise would be randomly injected.

Also, HDMI data is checksumed, see HDMI specification:

Toufu, if that were the true then the Wegrzyn HDMI cable would look the same too...faded and missing details .. ???
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Hifisoundguy, it would not be likely for digital artifacts to show up as faded or missing details.

For analog tranmission, yes, since the output of analog is a direct product of the signal being transmitted and if cable is suspect, then result picture/sound can appear as if there were filter applied to make the picture look distorted, faded, etc.

But for digital, the analog is first encoded to digital and then the digital bits are converted to analog to transmit the signal, then the analog signal gets picked up and converted back to digital and finally to analog again. So any noise in the transmission would not appear uniform such as that the noise introduced fades the picture.

Think about back in the days of analog TV signal, if you don't have clear signal, your picture looks distorted, but at least in a recongnizable way. But if you have an HD antaena to pick up digital signal, you either get a picture or you don't. Or if it locks on a weak signal, you can see the digital artifacts very clearly (blocks of green or bad pixels).
My 2 cents is try to find out if the cable you're interested in has a good reputation for staying in the HDMI port. The HDMI connector is inherently flawed in that it is a small plug that relies on friction to stay in. Some HDMI cable connectors simply fall out of the port, particularly if the cable is stiff or heavy. I had bad luck with Audioquest in this regard. If you get the cable home and it doesn't make a tight connection or risks coming out of the port, get another cable.
On my TV the HDMI cable was much worse than the component cable. That said the HDMI cable was a freebie from the cable company. Also maybe there was something wrong with the HDMI output on my cable box. I would try both and use which ever is better.
I bought some hdmi/cat 6 cables from monoprice and like them for the price and solid build quality. I dislike Monster video cables for their high margin and marketing stuff, but to say there is no visual difference between Monoprice hdmi cable and Monster HDMI 750 and up cables by Cnet and other people is just beyond my believe. Car in casino Royal looks more shiny and vivid from Monster cable than from Monoprice when bond pull over the car to pick up the aribian lady. My own HD home video looks more fuzzy from Monoprice than Monster when I quickly pan the lense from left to right. I like to say Monster cable is snake oil, but I can't.