Cable length and signal degradation.

[evil_ash_xero]

I'm trying change some things about my setup, mainly to get a better picture. However, there are some things that I can't really alter too much. I have heard many people say that your video signal
will degradate, the longer the cord is. Does anyone know when this will start to happen? How bad does it get? A lot of my systems have close to 6 foot cords, that then go into a component converter. After that,
it's about 3 feet to the switch box. That's 9 feet already. On that particular setup, I have to use, at least, a 12 foot cable to reach the larger television. That's 21 feet. The only thing I have noticed make my picture look worse, are switchboxes that weren't so great, or component converters that were knock offs. The bad converters would make the colors weird (whites would look yellow, bleeding), and the bad switch boxes would make the picture dimmer, and less clear.

If it does make your picture decline, is there anyway to combat this? Maybe using shorter cables with powered splitters? Maybe that will amplify it, and keep the signal from getting worse? I've read of line amplifiers, but I have no idea. My component converters are powered, as is my switchbox. But there's still (at least) a 12 foot cable from it, to the TV. This is to a CRT, in case that matters. I also use Monster and Belkin cables, most of the time.

What do you good gentlemen know about this?

I've found this link, but it seems a little too "good to be true". 100 ft?? https://www.showmecables.com/blog/post/ ... udio-video

[nmalinoski]

I think, in general, powered switchers function as repeaters, whereas passive switchers function as extensions. Good cables with larger-gauge wire should help decrease attenuation, which will increase max distance before you start seeing issues.

As for cable length for analogue signals, I think 12ft is plenty safe for a good-quality cable; I bought a couple 10ft/3m Kabeldirekt SCART cables a few years back (they were significantly cheaper than the 6ft/2m model), which are better than unbranded ones, but still not well-regarded for some reason, and I never noticed any signal issues when using one between my Behar Bros Toro and my OSSC.

Honestly, if what you have looks good to you, if you're not seeing any aberrations, I don't think there's really anything to do. How are you looking to modify your setup?

[evil_ash_xero]

Well, I'm trying to shorten the length of the cables, or get line amplifiers. And I've had to completely switch what kind of switchers I was using. Unfortunately, I have to wait until early October, for the ones I have ordered to come back into stock.
From what I am getting from what you're saying, the cables before the powered switch kind of don't count (in terms of length), as they are just amped and repeated thru the switcher?

So, instead of having 14 (I did have 16 ft) foot cables (from the switch), maybe something like a couple of shorter ones, with some kind of line amplifier in between, might help out? Where do you get component line amps, anyway? This component cable stuff, being pretty obsolete, makes it really hard to find things for them.

That being said, I recently got a powered component splitter. Would that do the job?

[Josh128]

Wire length increases both resistive and capacitive losses. Its physics.

[evil_ash_xero]

Wire length increases both resistive and capacitive losses. Its physics.

Yeah, but at what length is it noticeable? And what can be done about it?

[Guspaz]

If you're ultimately going to digital, do that conversion as close to the sources as you can. Don't like, plug all the consoles into a component switcher and then run a 10-meter long coax component cable to an RT2X/OSSC right next to a TV, put the RT2X/OSSC right next to the component switcher and run an HDMI cable for those 10 meters. As long as the HDMI cable is high enough quality to pass the signal intact, there won't be any degradation.

[evil_ash_xero]

If you're ultimately going to digital, do that conversion as close to the sources as you can. Don't like, plug all the consoles into a component switcher and then run a 10-meter long coax component cable to an RT2X/OSSC right next to a TV, put the RT2X/OSSC right next to the component switcher and run an HDMI cable for those 10 meters. As long as the HDMI cable is high enough quality to pass the signal intact, there won't be any degradation.

It's all analog.

[Guspaz]

Then, minimize hops/repeaters/conversions/switchers/lengths as much as possible and use coax where you can.

[evil_ash_xero]

Gotcha.

[Dochartaigh]

I think if you use quality cable, and everything is working within spec, this is kinda a moot point. I use 25 feet BNC cables (for Composite, S-Video, Component, RGB, and RGBHV/VGA) through my Extron Crosspoint switcher, with quality (mostly Extron) cables, with no problem whatsoever. Literally for years. On about 30 different setups/layouts of my game room. The Crosspoint only ups the voltage on the sync lines too I think, so CV/YC/YPbPr is still the same voltage as it started with and it's still fine.

I've run 50' on occasion to the other room and it still looked crispy. No muted colors, darkened image, ghosted outlines on anything, static, etc. Just works.

I don't think 25' is insane either (maybe a little, but not by much). Even if you're using one of those super popular Ikea/Target Billy Bookcase cube furniture setups, just to properly hide the wires you have the potential to have to go like 5' down from the console, 5' over to switcher or whatever, then 5' back up to a CRT just to hide everything properly – that's 15' right there. I have a full-height server rack with two desks next to it and use nearly all of that 25' (giving some room to pull stuff out if need be).

[thebigcheese]

I mean if you want to be technical about it, signal degradation happens the the entire length of the cable regardless of the quality of the cable, but it will happen less with nicer cables. It'll also depend on the type of signal. For example, unbalanced, high impedence audio signals (like guitars, probably most audio from consoles) has noticeable degradation (for me) at 12 feet. Balanced, low-impedence audio signals (like microphones) can carry for like 100 feet with no noticeable loss in quality. You can also insert buffers like active signal repeaters in the chain to extend the length, but these will alter the signal to some extent. And then there's digital signals, which don't really degrade at all but do stop working at certain lengths depending on the type of signal and quality of the cable.

TL;DR: minimize the length if you don't want to deal with signal loss. If that's not possible, active repeaters are the next best option.

[SamIAm]

There is an interesting effect that happens if you don't use impedance-matched coaxial cables, which in the case of video is of the 75 ohm variety. You start getting signal reflections around the point where the length of the mismatched cable exceeds one quarter of the wavelength of your signal. You literally have to do some calculating with the speed of electricity and the length of whatever non-coaxial cables you're trying to use to see if you're vulnerable.

On one hand, if you're playing old games, the dot-clocks are bound to be so slow that you won't run into major trouble until your cables are around 4 meters or so. On the other hand, if you want to be super-strict, the transitions from one pixel to the next can happen very quickly even with low-resolution games, and you have to think of those transitions as being much higher frequency than the dot-clocks themselves. In this case, you risk seeing very small-scale signal reflections when your cable is longer than only 50 centimeters or so.

So, if you're using six feet of cable, you're not going to see major trouble, but you might see very minor trouble, IF you're not using 75 ohm coax.

Anyway, as others have said, you get more resistance the longer your cable is. However, you get less resistance the thicker (and hopefully higher-stranded) the cable is. Also, copper gives less resistance than most other metals. 100 meters of thin steel cable can have tens of ohms of resistance to it, but 100 meters of thick, quality copper cable can have only a few ohms.

This is important when choosing speaker cables, too, incidentally.

[evil_ash_xero]

I'm using a powered splitter on the stretch that needs about 12 feet of cord. One cable is a Monster 8 ft, and the other is a 4 ft Monster. I'm using a ShinyBow powered splitter. I have some other types, but they cause the weird flash effect, that happens in certain Genesis games. I have talked about that in a couple of other threads.
Monster has always had a reputation as being a good cable, but overpriced. Obviously, you can get them for a fraction of what they used to cost nowadays.

The picture looks quite good. I was using some other devices before, and some things looked a bit blurrier than they do now. Maybe it's placebo. Hard to say. It's a big TV, so you can really get an eyeful of things. It's a 36 inch Sony Trinitron CRT.

That being said, I still have to wait for my new switchboxes to arrive, as my Impact ones are causing some dimming, and things look less sharp. I'm getting the gcompsw (this could really use a catchier name), which has been recommended on this forum. It seems to have a very good rep. So, hopefully it will be smooth sailing from here on out.