DVI cable vs. component

Carlman · « **on:** 27 Feb 2004, 11:45 pm »

I did a search and couldn't find this basic question answered.. So, sorry if it's 'Starting Block' material but, here goes:

Has anyone compared the picture quality difference of DVI to component cables? Is it better/different/worse...

I have a new TV that has the DVI port and I have an HD cable box that also has this port. I just thought it would be neat to try... I think it's cheap as well... I've seen the cables for around $20 at computer parts stores so, it'd be a cheap endeavor but, I'm not sure if I'm looking at the right thing... it 'seems' right anyway. So that's why I *think* it'd be cheap.

Anyway, any advice on using a DVI cable would be appreciated.

-Carl

JoshK · « **Reply #1 on:** 27 Feb 2004, 11:54 pm »

The idea behind using a DVI vs Component cables is similar to using the digital output on a CD player vs. analog outputs. DVI outputs a digital signal so the internal video DACs in the source aren't used (your HD box probably doesn't have the best DACs). The TV accepts the digital signal and processes it directly as opposed to having additional D/A and A/D conversions.

bubba966 · « **Reply #2 on:** 29 Feb 2004, 11:32 pm »

Josh said it pretty well.

Bu using a DVI cable (either DVI-I or DVI-D) you're bypassing the D/A conversion in the source sending a digital signal straight to the display/processor. You're also skipping the A/D conversion that would be done on digital displays by using a DVI cable over a component cable.

Using a DVI cable should be significantly better as you're skipping D/A & A/D conversions.

Carlman · « **Reply #3 on:** 29 Feb 2004, 11:43 pm »

The concept of using a DVI is as I'd figured... I just didn't know if anyone had seen the results in a comparison...

I was also curious to find a good source for this cable. I'll probably just get the standard one available at a PC store unless someone has any suggestions. I'm not trying to do anything fancy, just DVI output to DVI input... male to male I believe..

I hope using the DVI cable works for all channels and not just the HD ones... that'd be pretty inconvenient otherwise.

Thanks,
Carl

bubba966 · « **Reply #4 on:** 29 Feb 2004, 11:50 pm »

Carl,

Give these guys a shot http://www.pacificcable.com/DVI.htm

I know a few people ahve bought cables from them and been happy with them. But I've not dealt with them myself yet.

hometheaterdoc · « **Reply #5 on:** 1 Mar 2004, 12:04 am »

it depends on what kind of display you have whether or not you will notice much of a difference....

If you are using a CRT rear projection television, chances are you will see less of a difference than if you are using a digital display device (either LCD or DLP). That's not always true, but is a general guideline...

CRTs are analog devices... so even though you are sending it a digital signal (DVI), it still has to be converted to analog inside the television. So, instead of being at the mercy of the DACs in the source device, you are now at the mercy at the DACs in the television...

I've done comparisons of component vs. DVI on CRT televisions and it was really difficult to tell the difference provided the cables were decent and of reasonable length, the source equipment was of similar quality, etc....

Carl,

If you are using short cables, I don't know how much (if any) difference you will notice with your set...

Also, I don't know if things have changed in the past two months... but the DVI port on your cable box, if it is the one I am thinking of, is NOT enabled....

bubba966 · « **Reply #6 on:** 1 Mar 2004, 12:11 am »

hometheaterdoc's post just reminded me of something...

You should make sure the DVI out on your cable box isn't DVI-A (analog). DVI-A is basically running component video on a DVI interface.

bubba966 · « **Reply #7 on:** 1 Mar 2004, 12:27 am »

Here's a little help for identifying what type of DVI connector you have.

Carlman · « **Reply #8 on:** 1 Mar 2004, 12:41 am »

I'm using a Sony 46" RPTV.

I'm using a Scientic Atlantic 3250 Cable box... I didn't even think about it not being active... but, I'll bet you're right about that. Oh well. They included a bundle of cables to use, R,G,B, and L&R audio, all combined into one white cable. I thought that was kind of nice. I'm using it now and the HDTV picture quality is excellent. Regular channels are fair as usual. If satellite gets easier/cheaper to deal with, I'll change over to that down the road...

Thanks for the heads up.

bubba966 · « **Reply #9 on:** 1 Mar 2004, 12:55 am »

Carl,

IME Sony display's don't handle analog signals as well as digital signals.

If your DVI output on your cable box is hot, and it's not a DVI-A output, I'd give it a shot.

Hell, it's only $24 for a 3m DVI-D cable at Pacific...

TheChairGuy · « **Reply #10 on:** 1 Mar 2004, 04:58 am »

Carlman,

Don't have a DVI connection on either TV or DVD right now (tho I'm looking), but a did upgrade my computer monitor to a nice 19" flat screen recently. Lo and behold it has a DVI out connection (built-in hard wired, handy!).

So, for $150 or so I upgraded my video card in the PC to a newer one with DVI connection....oola

The darn icons and everything else on my screen friggin float now. Really, much more 3 dimensional now.

If the DVI connection can do the same on your video system, you are in for great improvements.

FYI - Radio Shack sells Monster Cable DVI connectors now...I think it was $99 (don't know length, but probably video 'standard' 2mtr)

lcrim · « **Reply #11 on:** 12 Mar 2004, 10:09 pm »

I have a Sony CRT (34XBR800) and a Real Digital 22" LCD both with DVI ports. There are service menus that can be accessed on both devices that allow technicians to adjust the settings on the inputs to optimize picture quality. After a recent calibration by a professional, the differences between a DVI input and a Component input are impossible for me to discern on the Sony CRT but on the LCD, DVI is slightly but noticeably better, probably due to better pixel mapping.