There are bad cables out there that do degrade a digital signal to the point where the receiving end won't properly recognise what has been sent. But that will mostly happen due to bandwidth limitations, dampening or interference through improper shielding. HDMI has introduced several standards over time, just like the CAT system for ethernet cables. You don't have to buy the super expensive stuff but if your TV set needs HDMI 1.3c, you'd better not connect it with a 1.1 standard 😊
My tired eyes & ears can't tell much difference nowadays. My wallet can, though. I still use a 30 mHz analog scope, VTVM's and even an old school "analog" TV antenna on the roof. I even prefer my old TS-520 to my shiny new Alinco ham radio...
Good point Paul. I have a friend that works at Best Buy and she told me that the mark up on hdmi cables is insane. I bet if Best Buy had a $200 cable that the store got it for about $8. It that bad people. Thanks for the video, nice job as always.
My dad spent about 40 quid on an hdmi cable "with internet" from Currys (a UK electrical shop). I have no idea what an internet hdmi cable was. Anyway, I told him to return it to the shop and get his money back, which he did. I then fished out an hdmi cable that I had in a draw that cost about a tenth of the price. Needless to say, the cheapo cable works completely fine.
Well, some cheap cables doesn't have some pins connected, and some cannot preform very well over the greater distance. Same apply for displayport cables. So yeah don't buy cheapest cable, but do not buy overpriced too. Get a cable from well known brand and you will be just fine.
When i bought out first hdmi tv and i asked for a cheap hdmi cable, i was told by the sales person, "we dont do cheap cables it degrades the picture to the tv". I replied, "its a digital signal, it either it gets it or it doesnt, theres nothing in between" Isnt there also a check ditgit on hdmi do it can even get a wrong signal and it will be corrected by the TV?
@@Arvidje - It turns out that long cables can cause enough impedance mismatch, crosstalk and reflection that it will affect the digital signal. It turns out that all electrons move through the wires in an 'analog world' but for short distances any twisted pair HDMI cable will work. As the cable gets longer then the cross-talk noise gets worse and impedance mismatch of the cable begins to produce reflective noise which you see in the black areas as noise. Sometimes you can add a Ferrite Core around the cable to reduce high frequency noise. I have bought these at Radio Shack and used them on long (20' +) USB cables which would not work reliably until I added a Ferrite Core clamped around the cable. If you loop the cable twice thru the Ferrite Core it will double the filtering effects of the Ferrite Core.
I'm an RF engineer and I will just say this, IF it's OK for the signal to transmit with wireless system with decent result (such as watching RU-vid with WiFi) than chances are the cheapest cable on the market that's properly made can get the job done for the same distance with absolutely no problem and no human detectable error whatsoever. Any wireless transmission is at least ten thousand times worse than worst copper wired transmission and with any distance the wireless signal can easily be trillion times worse, if RF connection can do the job than any copper can do it. it's simple physics.
Nice video! But as a long time home theatre enthusiast, I need to tell you that it isn’t quite as clear-cut as you suggest. I agree that you generally don’t need to spend $200 on a HDMI cable, but I’d be very wary of a cheap $8 cable. Cable length is also a factor. Let me explain: Although the cable is carrying a digital (on/off) signal, the frequencies involved are quite high (eg. up to 165Mhz for HDMI 1.0 @ 1080p). A cheap cable, with inadequate shielding and possibly higher resistance low grade copper conductors, will (without question) cause noise levels and slew rate issues which can result in the occasional incorrect binary levels being sampled (in effect, data errors). These occasional “bit” errors manifests themselves in pixel errors, which can indeed be seen! An example is what I like to refer to as “sparklies” in the image. Whether you actually notice these pixel errors / sparklies, depends on factors like screen size, and how attuned you are to noticing picture quality issues. Being digital simply means that you want a cable that is of sufficient quality that it always exactly replicates the high frequency stream of 1’s & 0’s from one end to the other. Unfortunately, I’ve experienced many "budget" HDMI cables that simply can’t reliably and consistently achieve that! So don’t just buy the cheapest cable, especially with longer cable lengths! Instead go for a trusted brand, and pay what you consider is actually reasonable, and in proportion with your overall system cost! Just don’t go crazy trying to save a few dollars by buying the cheapest “digital” cable you can find, on the flawed simplistic argument that “it will either work or it won’t"!
With digital there are usually three scenarios: - It doesn't work. - It works with visible artefacts and freezes. - It works perfectly. It's unlikely it works perfectly and then you only see a small artefact now an then. When it's not working perfectly it's usually very noticeable.
So true. Go for the cable that can handle the signals. As a pro A/V installer I can tell you it isn’t black and white. Zero or One. Every type of HDMI signal has its bandwidth. Just like network cables: a CAT3 cable will handle higher bandwidth signals, but for a very vert short distance. A CAT7 cable will transfer the same signal a much much longer distance. Cables have to able to cope with this required bandwidth. An old HDMI 1.0 1080p/60 signal will be fine with a short length cheap cable, but this cable will definitely not handle the modern 4K HDR or Dolby Vision/TrueHD signals. It’s all about bandwidth. So cheap badly shielded, badly balanced, thin cables will ruin the signal. And an overpriced marketing cable can be just as bad. My rule of thumb is to follow the standard (HDMI 1, 2, 3, etc.)
Actually there is a difference of a cheap and good cable. By your description, I dont need Cat6 cabling, I could use good old flat silver 8C cable on my network. And yes I use 8C flat for my switch interconnects of 1ft or less. but at 20ft, signal just dies? The truth: cable quality, shielding, impedance, capacitance, wire gauge. I use USB cables with active boosters in the lab, why? same reasons. I hate to say it, but someone with a $260 scope (that will mask a lot of issues) doing cable tests is not a valid test, use a more powerful scope along with two cables, your cheap one, and a good one, then compare the difference.
Correct, you need a scope with 10 times the bandwidth of the highest frequencies you are analyzing to be sure the scope is not affecting the waveform excessively. To look at 10 MHz Ethernet signals you would need a 100 MHz scope, at 100 MHz signal you would need a 1 GHz scope. That's why HP and Tektronix are still in business for high speed signal measurements
Paul, pal, and you know it gets even WORSE! No, not the signal you get on your cheapo "Dollar Club" HDMI cable, but a quick check on Amazon (And google) shows cables (2m) for $1495.95 and other places selling "high-end" HDMI cables for $4,000 even. Yep, but it's a shame and it's true: "A fool and his money are soon parted." Now I DO understand how people can be conned into this nonsense, but it's criminal that there are sharks out there taking advantage of people who really do not understand neither digital or analog, and how they work. (And if you go to Amazon you'll find that those cables get darn good ratings. BUT, it's because the "reviews" are just smart people making jokes about how "My pixels are now perfectly square!" and "I lost 20 POUNDS using these cables!" So on. They're worth the read.) :)
Thanks for sharing and demonstration. I would like to add that the quality of the cable does make a huge difference.. if the digital signal has a high frequency and the cable wires are for example not twisted and/ or not shielded you will quickly find out that the nice on / off signal does not look nice anymore at the other end of the cable. Same for incorrect impedance which will mess up your high frequency signal significantly.. I don't think you can just say: digital signals don't require any special cables.. that's wrong... Ethernet will not work if you use normal flat /untwisted telephone cable either..
If a HDMI cable is certified for a particular version, that means the cable meets the requirements and can handle the bandwidth. If an expensive piece of equipment has hdmi 2.0 and a receiver has hdmi 2.0, there is absolutely no reason to think an expensive cable would do a better job than a normal cable for the communication between the two ports. Both cables transfer the signal and the signal is translated the same way on both ends. An inexpensive cable is also shielded, twisted, etc. Digital signals normally have no need for special treatment. Just the specifications will do just fine.
@@gilbertcuoco that is true indeed. I guess if the cable can be returned I would certainly try the cheap versions first. Unfortunately I did find HDMI cables on eBay and other wholesale channels which claim to be HDMI 2.0 and certainly did not work reliable. A signal being digital does not mean the characteristics of that cable can be ignored. Characteristics such as impedance and shielding. Those can impact the digital signal enormously.
@@onnobeckerhof5790 True. There are manufacturers that cut corners. But normally when a cable is certified, you should be able to trust that that is the case. Of course not always when they come from Ali Express, Alibaba, etc. ;-).
Though I agree that $200 HDMI cables are a scam, there is no way every $8 cable is the same quality as every $40 cable. Especially with 4K. Often better HDMI cables has boost circuitry in them, or just better internal connectors and stability. Digital is digital, but not all cables are made equal.
Unexpected Maker I agree on both sides of it. To Paul's point, 90 percent of the time it would not matter. HOWEVER, If say you have a longer run like I do from a server closet to my living room, the voltage drop of the crap cable will make the "ONs" not register as on and the signal drop. So to your point, not all the time these cheap cables will work. I was able to overcome it with a HDMI booster, but as Big Clive would say "it's kinda jenky"...but it worked.
If an inexpensive HDMI cable works at all, then it will work exactly as well as any other cable that works at all. I run dozens of cheap HDMI cables and not one of them has ever failed to deliver.
I've had quite a few cheap ones that were terrible. Bending them near the cable end stopped the picture from displaying. I'm not saying all cheap cables are bad.. and on the flip side, you can get faulty expensive cables, but I've had personal experience with bad cheap HDMI cables, so I'll stand by my statement.
I reckon buying a reasonable cable that won't fail because of loose connections etc will still be a fairly cheap purchase compared to the ridiculously priced, so called 'high end', cables!
Unexpected Maker yeah totally agree they are not all made equal but they will either work or not work the difference in cost is usually the quality of the assembly.
I am a noobie and I've only found out what an IC was today, I wasn’t even sure what an oscilloscope did. Thank you for the video explaining. I hope your son is OK.
Great video, I am into building amplifiers and I never realized this until you explained it in this way, I am learning so much about electronics from your videos, keep them coming,,, nice job...
I had to go back and look but I got a 3 pack from Amazon "Gold Plated" for $8.99. They obviously don't appreciate the resource they have in the family. But then again if they have money falling out their pockets, why should they care. Except to give you $200 for your Amazon cable! Thanks for the good laugh!
There is one exception to this, which is long HDMI cables. Do not buy a dirty cheap 10m cable, because I can guarantee you that you'll have issues either immediately, or after several months (which is hell if you put it in a wall or something). And this also depends on the bandwidth, e.g. I wouldn't even buy a cheap 5m cable if it's for 4K, and for the new HDMI 2.1? Last I checked no reputable brand even sells them over 2-3m yet. When you want to send a signal, analog or digital, over those sort of lengths, the quality of the conductors (thickness, whether they're pure copper (e.g. copper clad aluminium causes *so* many issues with ethernet), etc), the quality of the insulation, whether that holds up around sharp bends, etc etc all matter. I'm not saying you should spend $200, but if you go with the cheapo cable don't be surprised if it fails. reddit/Amazon/etc are full of people who have issues with cheap (or even expensive) longer cables. If you need to go really long, you should consider buying a fibre HDMI cable. Those change the signal to optical and back, so distance doesn't really matter. E.g. we needed to install three 4K 60hz HDR cables in our wall + ceiling, and they had to be 20m, so we just went with three fibre cables from three different decent quality brands (we only need two and could make do with one, so one/two spare). Some issues with fibre HDMI cables though is the lack of power HDMI puts out, so I would suggest people get the ones which have USB power on each end, else you get issues with some devices which don't put out enough power to feed the optical converter.
I wonder how many, 'I only buy quality' snobs, have been caught out this way? To be fair, if your not techie, how would you know this is a con. The sellers (read 'conmen')have a lot to answer for!
A couple of my friend have spent £50 plus on HDMI cables, they don't like it when you point out you can get the same lead with the same tech for less than £10.
I have used many cheap HDMI cables and have never had an issue so far. I always try to keep the cable length as short as possible to lower chances of any data loss. In the past with analog any loss of signal would reduce signal quality drastically. Also any out side RF signal that get's into the data stream will cause faulty signals.
If you are transmit 4K signals to your tv from your PC I doubt it is possible to use a cheap cable. It is also stated that you need another class or quality cable. I have also seen sprarkling pixels om my 4K tv, for I am still using a cheap cable.
Do you understand a vídeo signal is made of millions of these pulses signals per second? Also, there are error correcting algorithms, so you only see errors when enough pulses are lost. Why would you think the cable would be good enough to transmit billions and billions of these pulses for hours, and then it would fail to transmit a bunch of pulses so you see a "sparkling pixel"?
It kind of reminds me of the snake oil salesmen of the audio industry with their polarized speaker cables lol $200!? I know there is a difference in a quality cable vs the $ store special but to scam people like that is just bad karma. Good video.
The only thing to consider is radiated electrical noise on very long cable runs when run alongside the mains cable... otherwise I agree that there is no point in spending stupid money of cables.
The only thing i would worry about is shielding and some really cheap chinese cables with low quality, oxidized metal. Same for analog AV cables. Just finished re-cabling my home cinema with mogami cables - good quality and not prohibitively expensive. No need for snake oil-level expense. As long as they have good, tight coax shielding, OFC copper and quality materials you're good to go
Hate to chime in here so late, but I thought we were going to see some Siglent scope comparisons.. but after hearing you complain about good quality cables costing more, I had to add. First, there is a difference.. I hope you've figured that out over the past 5 years tho. After figuring out you didn't even have a jig or comparison of the different cables, I was confused. I'm an RF technician and we can tell you all about signal propagation through conductors and dielectrics... and I think the part that eludes you is what is involved to make this difference. I have a phase-stable cable for my Anritsu site master, that 2m cable alone is worth over a thousand bucks! To a lay-man, that cable looks like a 2m RF cable with a couple of N connectors on it.. but there's more to it, and that is the same with A/V cables. I can see the difference in a picture with cheap cables ringing and accepting crosstalk from other signals within the cable shield. So unless you have a jig and appropriate signal generator, there is nothing you can say about which is better without guessing by appearance.
Cheaper cables mean smaller gauge wire that translate to higher resistance, also not as well shielded for noise. This is only a problem on long runs closer to 100ft. So buy cheap, try it out, if it doesn't work buy a bit better one. The main thing to look for is wire gauge.
200$ for HDMI cable. Really? That's very expensive. If you have a friend which can explain to you difference between cheap and expensive cable is it good, but not all have such a friend. Thanks for the video.
The explanation is only about voltage levels though. But, what kills you with these though is crappy slew rate on degraded cable plus more demands for more signal. if those square boxes he showed had tome gaps that are only 1/4 the duration of high sections, you would see weird garbage on your screen when you hook up too many monitors and run heavy 3D graphics for example. That's exactly what "overclocking" is - sure you can run faster, but those small transition blips will turn into errors in binary value instead of "doesn't matter noise"
If hdmi is all the same “on or off” why don’t cheep cables display a clear 4K 60hrz? I mean I’ve gotten the to work but input lag on games and tearing is an issue until I use correct spec high speed hdmi don’t get me wrong $200 is highway robbery you can get a high speed hdmi that’s sufficient for $50 but any amazon basic hdmi really does look much worse and now I’m more confused than ever as to why
ALSO WHEN CD PLAYERS FIRST CAME OUT THEY SAID YOU HAD TO HAVE SPECIAL TYPE OF AMPLIPHIER AND,OR RECEIVER TO PLAY THE CD PLAYER,BECAUSE YOU DO NOT NEED ONE.
Come on, this helps to redistribute the wealth and push business going. Dont try to educate the rich. In Australia we have HDMI cable made of platinum and silver, selling for $7999 AUD for just a cable
But Paul, you know what you are saying is bull crap says some audiophile while upgrading the spring loaded speaker termination on their amplifier because the $300 solid brass ones are going to give better bass lol. Don't laugh! A video exists of such a case! I tried to save him a lot of money but some people just can't be saved!
the video should have been about the difference between expensive low noise harmonized HDMI cables and ordinary cables... and maybe, similarly, johnson/nyquist noise and the application
no!you're wrong! the hdmi cable differs because it has other thin cables for other signals like hdmi ARC or other signals that are useful for other communication purposes! not only digital sound that as you've greatly explained on oscilloscope. so for this you pay extra...for othe communication purposes
learnelectronics: There is no better on , there is no better off. Expensive switch don't give you better light out of a bulb. If you can tell the difference, buy the $200 HDMI.
There is a difference between. HDMI. cables like any thing you get what you pay for now. what you BIL paid is a bit high. but the amazon basics one is crap
Hum yes ok I basically agree however the cheap ones will likely start to show problems if the length increases due to the capacitance and inductance of the cable. As these variables increase the signal will not be able to go from 0 to 5v as quickly and if it gets to the point where the signal is going faster than can be reliably transferred along the cable then you are going to get digital errors. So I wouldn't write off more expensive cables in all situations
I've seen cables so cheap that they can't reliably transfer a digital signal. Especially if they are very long. But in general, any decent cable will do.
The old "best buy monster cable" scam. There’s a sucker born every minute. There was a class action lawsuit against best buy that resulted in customers getting some of their money back on those.
I used to work for best buy. The cables are majorly overpriced. $20 cables were more like $1 for any of the inhouse brands. Actually, any of the inhouse accessories were like that. Super high markups.
The guys at Bestbuy will tell you to buy the expensive HDMI cables because that is what they are told to push and if you tell them the facts, they get defensive.
its not like that expensive cables are used where it has to be .. when the frequency is high the small noises will also be 1 or 0. Plz dont misguide people...
Glad someone else has the same take on over selling of the "HD" hype and understands the madness of people thinking they need more expensive cables, TV antennas etc. I watched a television advert the other day selling "HD" sunglasses! Bonkers!
Ok, so what exactly is an 'Expensive Cable'?? It all depends on the persons budget. Your brother and his wife make a lot of money, you told us so, therefore, he can easily afford a cable costing $200. He can obviously afford it and if it pleases him then fine. To people who are on minimum wage jobs and just about managing to put bread on the table, that would seem too expensive and we obviously have to go a lot cheaper. I wouldn't personally go Amazon Basics though, that's asking too much Lol, but I will buy a decent gold plated cable. Why buy an Escort car when you can have a Porsche if you have the money,..Right?? Is a Porsche a waste of money when an Escort can still get you from A to B!
@@learnelectronics Exactly my friend, and that's what I was telling you, it wasn't fair belittling your dear brother to the world just because he purchased something you disproved of. It's HIS money and he can buy what he wants!
Hmmm would not be so sure there are higher and lower bandwidth cables. How do I know? I have a monitor with very high resolution and only high quality more expensive HDMI cables work with that resolution. Now if you have the standard 1080p resolution then sure enough any cheap HDMI cable should do it, though it will make difference when you need to use a longer cable than your typical 6 feet
Yeah i understand, people who makes good money does this and would think your trying to cheapen them... there is always this battle...PC vs Mac...ebay vs amazon...Godaddy vs squarespace..Really anoying
This is likely not due to the cable, but due to poor quality of the power supply on whatever transmits the signal. Whatever it was, it was tested to ensure the switching noise from the PSU doesn't cross the threshold. And even if it did, it would fail the checksum on the receiving end and you'd get no signal at all
HDMI cables have a limit in length. Expensive HDMI cables that are long might have fiber optics or active signal booster. For 4K monitors you cant use any arbitrary HDMI cable. Take a look at Amazon and you will find different price ranges for different specs Yes HDMI is digital but when you transfer high speed digital signal over copper cable analog physics affect the digital signal. Reflections, capacitance, induction. (Transmission line physics)
Well, not quite. There's a handshake and a stream of packets... HDMI (even 4K) either will work perfectly for a given cable, or it won't work at all. It won't degrade the quality; it either works or fails.
Yes but when you drop packets it will be displayed as artifacts on the monitor. If large sets of data packets are dropped it will not work at all. Here is a video of a HDMI cable that can improve artifacts that cost 140USD. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-MjJzibFTaqA.html If you search the subject length and quality of HDMI cables you will learn more.
The only time it matters what kind of digital cable you get is if you're wanting to send something like 4K video to a 4K display device. In those cases, you don't need a more expensive cable necessarily - but you do need to have an HDMI 1.4 cable or better. The 1.3 cables max out at 60Hz at 1080P. They'll still work as far as getting an image on your display - but you'll be limited to lower resolutions is all. I believe DisplayPort also has a few different revisions that support varying degrees of image quality depending on the revision.
I've seen fiber HMDI runs cost $1,200 but that is very specialized. We don't know the specifics, for example, was it in wall? Plenum rated cables are quite a bit more than normal. You can I can get away with an $8 cable in a wall but a contractor must use fire rated cable. Was it a RapidRun brand multiuse cable? SlimRun? Fiber/copper hybrid ready to handle optical in the future? Etc etc etc. Anyway... 1. Do we trust someone who can't read the waveform levels on their oskilliscope? 2. Having installed dozens of systems in corporate and education settings, and troubleshooting systems installed by others that were not working well, or were working fine then started having problems, I can say cheap cables suck on a regular basis. Buy 20 and one may not work right out of the box, another may work but be flaky, and two more can start acting up after time. A brand that may be OK in a 2 meter length may be horrible in a 5 meter length since the longer the cable, the greater the signal is affected by poor quality. How about a cable that has crappy impedance which weakens the signal to where your digital peaks are near the threshold of what the equipment considers a digital bit high, or distorts or breaks the waveform with a loose connection? How about "gold plating" or what should be nickel plating under the gold is so flaky the conductors start to corrode over time? I could go on and on but hopefully people get the idea.
I've had a few cheap cables go bad over time. Fresh and new put of the box, cheap cable is fine. Expensive cable that gets man-handled with enough force will also go bad. Can't win 🤷
The only thing I would look for in terms of quality in cables for digital signals is simply the strength and robustness of the cable, but that's not even all that important for a tv, unless you're constantly moving your tv arround and plugging and unplugging cables.
But who needs an analogue cable that costs $200 either? The cable is either up to spec, which under the length of 20m it could as well be well under $20, or it's shit.
My AV rack got real picky with the new TV. I had a time swapping out HDMI cables trying to find 3 that would behave well with the various devices. No reason to spend big $ on cabkes, but don't get the cheapest either. Hit up Amazon or Monoprice. With Monster et al you're paying for the name and marketing.
I have great results out of my $4 eBay cables. No way would I let someone steal money from me. You know the cable probably cost less than $4 to manufacture probably under $1.
Well the really cheap ones can actually get "noisy" when the inside conductors stop sharing one of those on or off signals, this has happened to me twice and i saw some red lines at screen, but still working absolutely fine till i have to disconnect them and messed them up
