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Discussion Starter · #1 ·
Since Mid-March I've been demoing the new Granite Audio 420 digital coaxial audio interconnects/component video cabling.


It was my starting this demoing of this cabling that got me interested in even more investigating objective measurements of video cabling, plus the knowledge that Don of Granite Audio designed this cabling to meet stringent OBJECTIVE requirements, using a $25,000 plus Time Delay Reflectometer to measure each cable including connectors end to end to ensure proper objective quality.


Here's the thread discussing objective video cable (and digital audio coaxial cables, as same objective design parameters) standards:

http://www.avsforum.com/avs-vb/show...63&pagenumber=1


Here's some specs for the new Granite Audio video cabling:



MODEL #420 INTERCONNECT FOR VIDEO & DIGITAL-AUDIO



This ultra-high-performance Micro-75 series video & digital-audio cable has both 100% Bonded Foil and 96% Braid Shielding for the ultimate in crystal-clear performance, even in the longer lengths required in modern custom home theater systems. The #420 meets SMPTE 292M Broadcast Digital Standards (SDI) and delivers 1.51Gb/s HDTV brilliant quality signals up to 215 feet. And has an Extended Bandwidth of 3.01GHz. The characteristic impedance is 75 ohms, +1.6 ohms, and this new AV cable is available with one-piece 75 ohm RCA, BNC, or F connectors with an impressive High Return Loss of >34dB @ 1.2GHz. The #420 is engineered to deliver all the high-resolution picture and sound quality of your original DVD, D-VHS, HD Receiver, or CD source with full rich signal response and the blackest possible background.


The Granite Audio cabling has attenuation and return loss specs similar to Belden 8281B, with at 100 ft. 2.79 dB attenuation at 67.5 MHz, which is above line quadrupling and HD bandwith as noted in the above thread.


This is a real thin cable, clearly a good amount thinner than the Belden 8281B, yet it has top dog performance. And Granite Audio designed one piece crimp 75 ohm connectors, whether BNC, F-connector or RCA.


So far, I've been using the cables for component video, Theta Voyager 480p to Dwin Transcanner 2, and Toshiba DST-3000 to my Dwin Transcanner 2. Previously, Wireworld Gold Starlight (silver) component cabling was better than other video cables I had tried - even though it only had 50 ohm RCAs (many of the boutique video cables, especially being thick, can only have 50 ohm RCAs) and the other video cables had 75 ohm RCAs. Now, the picture is definitely sharper and clearer, the best its been.

That 75 ohm from end to end, 1.6 dB variance, is really [email protected]@@

Although I tried a 5M run to my Dwin projector of RGB H/V Sync cable and it looked really nice, I decided to leave in the Wireworld Gold Starlight (silver) cabling to my projector, so that I would only be changing one variable, the component cabling.


What I really like about these component video cables is not only their 75 ohm performance, but they're so thin, which makes it so much easier when you have a mess of cables connecting to components. And the connectors are just so solid, that they snap on and off easy but tight for a solid connection which is so important.


I have both a Toshiba DST-3000 and a Samsung 165 OTA ATSC tuner. The Toshiba connects by component, the Samsung by a 15 pin VGA cable (Better Cables Ultra - Granite Audio does not make this cable, even for me). The VGA connection into my Dwin Transcanner 2 was measured by Michael Hamilton as having the better picture, more flat to 6500 degrees across the IRE scale - altho the component is still darn fine. And I could watch say PBS OTA in 1080i and the Samsung 165 OTA picture has been clearly better. Well, interestingly enough, now, with the Granite Audio video component cables, it is too close to call, the pictures look about equal. I also have a JVC D-VHS VCR, and traditionally when I record an OTA digital channel from my Samsung 165 via the JVC, I want to watch it through the Samsung via its RGB output as the picture has been better that way. Now I am finding that the picture quality is equal using the component video out of the JVC with the new Granite Audio component cabling
 

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Discussion Starter · #2 ·
I also had Granite Audio make up some F-cables for me to try. The F-cables hookup to a splitter for my OTA antenna, two 2M to an RCA Ultimate TV and a JVC 9600 S-VHS VCR, and two 1M to Samsung SIR-T165 OTA receiver and also Toshiba DST-3000 DirecTV HD and OTA receiver.


I did some immediate A-B testing with the F-cables and they seemed on HD stuff with the Samsung 165 (local PBS HD stuff) to simply be equal in picture quality. But I left them in and over about two weeks time I noticed - what I definitely feel are picture quality improvements.


I must be nuts. Because the "old" F-cables are Belden 1694A with snap on 75 ohm F-connectors terminated by a friendly custom installer using proper crimping tools. But I know what I'm seeing, I live with my video system.


And I've noticed a bit of picture improvement watching NTSC stuff on occassion with my JVC S-VHS VCR tuner; but frankly, more and a real nice improvement watching a few shows on my RCA Ultimate TV receiver.

On the latter, channels likeTBS, TNT, Sci-Fi are frankly too compressed and pretty crappy looking - but more recently they have actually looked much better. I really wasn't expecting this.


Its good that, as I mentioned above, I left the Wireworld silver 5M cable from my Dwin Transcanner 2 to my Dwin CRT projector - this way, I didn't change too many variables.
 

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Discussion Starter · #3 ·
I still haven't decided on replacing the 5M BNC to BNC RGB H/V Sync cabling from my Dwin Transcanner 2 to my Dwin projector.


First of all, I am just SO in luv with my current picture, I don't feel like tweakin' right now.


I will get around to it at some point.


Meanwhile, Mark Burnstein in Michigan has a 30M run (I should say had) of Belden 1694A with Canare 75 ohm connectors to his 8" NEC CRT projector and some component cabling. Well, Mark and I are good friends, and Mark was interested in trying the video cables - so he did last weekend, with Jeff Bryngelson present for the evaluation. Result - Mark is keeping the Granite cables in his system. I'll let Mark come on and tell you what he thinks.


Extraordinaire custom installer Mike Parker (who won best of CEDIA $150,000 and up home theater two years ago) also demod cables with his system, I think only DVD and NTSC so far, and he will shortly be trying them on HD, too. Again, I'll let Mike fill you in, but lets just say he already wants to know how much if he buys them. HAAA! (I'm not the one sellin' them - I'm just the DEMOER/END USER).
 

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Discussion Starter · #4 ·
Now I've told you some really good things about these video [email protected]@@


Time for the bad. Companies like Belden and Canare sell in mass - they can manufacture quality video cabling and connectors in bulk and make a profit selling it for a lot less than a company like Granite Audio. Don of Granite Audio worked with his own design team, speced a brand new thin video cable with super high bandwith a low attentuation and other top notch specs, they also designed real 75 ohm one piece RCA and BNC and F-connectors as well, they also have a $25,000 TDR for design and testing and quality control purposes (Granite Audio is doing a picture graph of impedance for each video cable - Don, could you post a picture for us?), and they also designed and manufactured their own special crimping tools, too.


So the catch. Simple. Granite Audio has a substantial investment of time, money and resources in these new video cables. Pricing therefore ain't "cheap" - but frankly, not as expensive as many "boutique" video cables on the market; and these cables will satisfy the most demanding objective specs and TDR testing. But these cables may be too expensive for some folks and I can appreciate that. Hey, they're certainly somewhat more expensive than Monster's best component cables, for example, -

but note that MOnster's literature doesn't anywhere state that its RCA connectors are 75 ohm.


As to whether the connectors make that much a difference. Objectively, you will find different opinions about this among objective "experts".

Mike Parker has stated his opinion that the connectors are very important, each connector in a chain of video cables from component to component eventually to video display makes a difference. I've been told this by none other than Joel Silver of the Imaging Science Foundation, that attention to proper termination is real important to the best image quality. Now Greg Rogers of Widescreen Review didn't seem to feel that the wrong connector would likely have a visual impact based on long video wavelengths and I also respect Greg highly.


But at least we have video cabling here that satisfy stringent objective requirements, and whether that makes a difference subjectively as well you can determine.
 

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Discussion Starter · #5 ·
I should add that Granite Audio (Don Hoglund the main cheese) got interested in designing these cables after our Az Audio Video Club video/coaxial digital audio cable DIY cable building and Time Delay Reflectometer meeting about a year ago. So many of the boutique cables tested not very well on the TDR. So Don got interested in designing and selling cables that worked well subjectively and tested correctly objectively. I think he's really succeeded.


This is a cable thinner than for example Belden 8281 (RG-59). Yet its specs are better, and its attenuation is similar to the Belden 8281. Its a real winner. And it has a super high bandwith, up to 3 GHz!


Mike Parker used to work in Pro Audio and Video, in the STUDIOS and patch bays. Mike mentioned to me some cabling they used for patch bays, thin cabling like this Granite Audio stuff. But that cabling only had bandwith to 200 MHz, not the lower attenuation of the Granite Audio cabling.


On the other hand, the Granite Audio cabling, as does Belden 8281 (RG-59), do have a higher attenuation than say Belden RG-6, which is a much thicker and less flexible cable. I can "see" where over 1 and 2M runs, hey, another fraction of a dB of attenuation is unimportant vs. the gain thanks to cable construction and perfect one piece 75 ohm connectors of the Granite cabling.


But what about the 5M run to my projector? Might that extra bit of attenuation compared to thicker cabling make a difference??? I calculated that the extra attenuation of the thinner cabling would be less than .2 dB over a 5M run - I betcha that is more than made up thanks to the connectors on each end. But I don't know for sure, until I try. And one of these days ISFer Michael Hamilton's coming back with his ISFing stuff and he'll objectively and subjectively see what he thinks. Stay tuned.


Keep in mind that my current 5M run to my projector is a Wireworld silver and quite thick BNC to BNC cable, that we checked on the TDR and it is quite close to 75 ohm end to end. A great cable. And visually it kicked butts with some Belden 1694A with Canare connectors, and some Canare cabling and connectors, that I had. So maybe for the 5M run the Wireworld silver might still be better in my system. But its retail is way higher than the Granite Audio - what I'm saying is that the long length of Granite Audio video cabling retails I think for about 1/4 of the Wireworld silver (sure, I got a good deal as a reviewer, but I still payed too much for that Wireworld silver cause I couldn't live without it. Then Don had to go design his own video cabling the shm-ck.
 

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Hi Steve,


Here's a small photo of the TDR screen showing one of our new Micro-75 cables under test.

http://www.graniteaudio.com/photo/tdrs.jpg


For those with DSL who want to see a bigger photo, try this link.

http://www.graniteaudio.com/photo/tdrb.jpg


NOTE: Cable tested on Tektronix TDR. Starting at the left of the screen, the first portion of the trace is on the 50mp/DIV 50 ohm Reference line and represents the 50 ohm Reference Loop Cable between the Pulse Generator Head and Sampling Head. The next trace portion represents the interface cable between the Sampling Head Input and the cable under test. The bold vertical line represents the start of the trace of the cable under test and includes the terminations of the finished cable. This last portion of the trace to the right of the bold vertical line will be on the 75 ohm line, with no deviations, if the cable & terminations under test pass the test.


I'm testing all our cables at 50 mp/DIV resolution, which is very good. This is the better specs. This is the scale on the far left. We can also test other's cables at 100mp/DIV and 200mp/DIV, which are the scales on the right. This will be for the weird cables that are all over the place on characteristic impedance, and their traces wouldn't even be on the scope screen at the tighter 50 mp/DIV scale.


Steve, I have objective proof that the impedance of the connectors can be shown on the TDR to effect the trace of the entire circuit under test, including the sections of cable that preceed the connector. I've not had time yet to photograph these traces, but I will as soon as I can and post them here.


I'm really excited about these new Micro-75 cables. I've actually been working on this project for over 2 years. Thanks to the success of all our analog cables, our good customers have been bugging me for 3 years to get into the digital & video cables so they could get more synergy and cable their entire system with Granite Audio. It has taken me two years to get up to speed on specs & engineering, and to come out with something worthy of our reputation.


We've only been offering these new Micro-75 Series cables for a few weeks and they've already been discovered by the cable reviewer for DVDetc print magazine. And, he will be reviewing them later this month. I will be shipping him 4 of our 6 new models for review.
 

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Discussion Starter · #7 ·

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Don I have 2 questions,


Why is the trace so noisy. Is there something wrong with your

step generator. My 15 year old Tek TDR is nowhere near that noisy.

Some of those noise spikes look to be in the gigahertz region.


On the same scale what do some of your competitors cables look like.

I certainly know the answer, but for everyone else to have a reference

you should show pictures of some of the standard stuff.

Belden, Radio Shack, Other Trendy expensive stuff...


Pictures of the aberations caused by various kinds of cable connectors

would also be nice.



Steve, It is not the flatness of the trace that is of primary concern, but

the number and frequency of the aberations. In particular pictures of

a few of the twisted cables are quite interesting.
 

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Hi Kevin,


Which model TDR do you have? What settings do you use to test 75 ohm cables on it? Do you have the model with a printer or can you take photos of your screen?


We tested some cables at our club meeting last year where the trace looked like the skyline of the Swiss Alps. One cable had a trace that ranged from a low of 5 ohms all the way up to 117 ohms. It was advertised as a 75 ohm video cable. But, there wasn't even 1% of the trace on the 75 ohm line. I will publish some of these traces when I get access to the cables and have the time to put up the photos.


Don.
 

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Discussion Starter · #10 ·
I suspect that if anyone wants their video cable TDRed, that they could for a small fee and payment of shipping both ways ship it to Granite Audio and then a TDR picture could be taken.


My recollection of our Az Audiophile Society cable building and TDRing session was that none of the cables tested looked any straighter across as 75 ohms as the photo above. And of course many didn't look good at all, some absolutely horrid.


Don, how about posting photos of your RCA, BNC and F-cables and identifying them, of course with the connectors crimped on each end, and identify the length of the cable, too. Thanks.
 

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Steve, Don,

thanks for the opportunity to experience these wonderful cables. I still have not had a chance to complete my testing, but so far I'm very inpressed with what I've seen so far.


In my opinion the the scope display looks very good. The noise could the result of the generator (and you'll be hard fetched to find one that would not display any noise, especially at 2ns) or it could be the results of a extremely clean TDR. And Don, I doubt if a 15 year old TDR would show that level of noise, unless it's in tip top condition, because it's common for any CRT device to loose it's pitch performance (resolution) with age.


My question has more to do with the length of the cable under test. Because for my application, I'm very impressed with the "flatness of the trace", but the distance of the cable under test should be the most important issue here. Because if the cable is able to produce that flat response at a reasonable distance and still be able to show the subtleness of very high frequency noise -- that's a good thing.


I don't own a TDR, but do own a couple of very fast scopes and some neat equipment and test patterns. I'm testing the cable that I have for square wave performance, to include actual image comparisons on a 9" Marquee CRT projector (most important to me). I also have both Belden 1505A and 1694A to compare it to. So far, I'm impressed. I'm puzzled as to how it's able to perform so well and be so small in diameter. In theory a small diameter cable would have a high frequency rolloff at certain distances.


I have one more test (1505A, 1694A, and HDTV using a JVC D-VHS deck), then I'll post back with my findings.


BTW, I'm not an HT installer, I'm the techie guy that you had on your guest forum. Mike Newman won the award.
 

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Discussion Starter · #12 ·
Mike, I turned 50 last month and my memory is going. SORRY!!!!!!!!!!!!!!

Gonna have to get my head scoped on that TDR!!!!


Mike, as you said, I too am puzzled by how such a thin cable can have such great performance. As I said above, for short lengths like 1 to 2M, I wouldn't think a bit of extra attenuation, typical of thin cables, would necessarily matter (and the one piece connectors, 75 ohm, sure give a great benefit) - but it sure may compared to good ol Belden 1694A RG-6 for longer lengths we typically have from scaler or video processor to say a CRT projector. And that's why its good that you're playing with the cable and giving us your thoughts.
 

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Steve,

I turned 50 in March, so I understand. Now it seems that the only thing that I can always remember is when I was able to remember.
 

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Discussion Starter · #14 ·
And Don turned 50 a bit over a year ago. Seems like we have a 50 and over cable club [email protected]@@
 

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Hi Mike and Steve,


Steve's right. I'm 51 now. And the party's over on being able to eat anything, anytime, in any quantity. In my college days I could eat 4 times as much and never gained a pound. My weight was plus or minus 2 pounds, no matter what, for 30 years. Things are different now. ha, ha.


Thanks, Mike, for the compliments on the cables. As an audiophile, we generally think bigger is better when it comes to cables. Of course that's primarily true with analog or high current signals. But digital & video are high frequency and low current, just the opposite of typical analog or power cables. These Micro-75 cables were designed from a philosophy of "form follows function". And so they ended up skinny, like I used to be. ha, ha.


I certainly participated in the design of these cables, but so did several others with much more technical digital/video cable education than I. So, I may not be able to answer every question myself, but I will get answers to everything that's not proprietary.


Mike, what length of cable would you like to see a trace of? Also, there are many settings on this TDR that will alter the trace information and reduce the noise on the trace. My primary goal with the photo above was to show how "flat" the trace was at 75 ohms for the cable and connector, and to get a photo of it with my digital Sony camera. The best high resolution trace with the least noise was the hardest to capture with my camera. It would be different with a film type camera. Anyway, let me know what length you'd like to see and I'll make one up and get the best trace photo I can to post back here.


Speaking of being over 50, my friend of 30 years, Mike from Prescott was saying over lunch just before CES2003, "Don, we used to talk about women and fast cars. Now all we talk about is our aches & pains, and what we're going to have for our next meal." ha, ha. If you're under 50 that sounds scary. But, after 50 it's, "So, what's the problem with that?" ha, ha. Life is perspective. There is no reality. ha, ha.:D :D :D
 

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quote

Which model TDR do you have? What settings do you use to test 75 ohm cables on it? Do you have the model with a printer or can you take photos of your screen?


1503C with a couple of options including the POS thermal printer that

never worked. Has outputs on the back for a real scope. RS-232 port

that hooks up to a computer. Supplied computer software about as good

as the thermal printer. Raw data is available however. One of the nice

features is the ability to zoom into any 1 foot of a cable over a 500 foot

length.


These days a TDS8000 with an 80E04 works so much better. I still

hate digital scopes.
 

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Quote:
If you're under 50 that sounds scary. But, after 50 it's, "So, what's the problem with that?" ha, ha. Life is perspective. There is no reality. ha, ha.
The really scary thing about this is that it sounds so much like something we were taught before starting school. Remember "row, row, row your boat"? (Everyone sings in unison), "merily, merily, merily, merily, life is but a dream" :D :D :D Strange how simple things change their meaning over time.:D
 

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"roll, roll, roll your TDR. Gently down the screen."


Hi Kevin and Dan41,


I'm using the TEK 7S12 TDR with changeable pulse and sampling heads. It will also scroll the cable to 500 feet and zoom in on one inch of cable. This is handy for zooming in on the termination. For example, I can zoom in on just the connector and make it fill the whole screen.


It will even test 2 cables at once and show a dual trace if I get the extra module. Would be interesting for side-by-side comparisons?


Earlier today I made up a 215 foot cable to take a TDR photo of for Mike mp20748. I picked that length because our cable is spec'd to deliver full HDTV bandwidth out to that distance. And, even Steve Bruzonsky didn't need that long of a cable in his maximum HT with high ceilings. ha, ha. Of course he may need longer cables when his cracking walls fall away completely and everything gets more spread out. ha, ha.:D
 

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Why Granite?


Why not just buy belden w/ Canare connectors at a tenth the price?


-Brian
 

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Discussion Starter · #20 ·
Hi Brian. Legit question. The question is does the Granite cabling outperform on a high resolution video display the Belden 1694A/Canare connector cabling. I have compared a number of video cables over the years, including that combo, and I found that it does. Mark Burnstein had that precise cable/connector in his 8" CRT home theater and just compared and decided to go with the Granite Audio for not only short lengths, but for his 30' length of RGB V/H Sync to his projector. The end user must determine the value of paying for performance - and I would agree for most folks, paying too much even for perhaps better performing cables can be spent elsewhere in one's system opn better components or put in the bank. But at least we have here a video cable from a specialty manufacturer with real objective performance and measurements, which is too often not the case with boutique video cabling. The proof in the pudding is that the consumer who orders the Granite Audio video cabling, if the consumer has say good performing Belden 1694A and Canare 75 ohm combo, can compare the Granite Audio video cabling, and if it doesn't give enough of a performance benefit to justify it in the consumer's mind, I believe Granite Audio has a thirty day full refund return policy. At least that's the policy on non-custom length audio cables. Don, care to comment on the Granite Audio policy re video cables return for refund??
 
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