|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
73.153.246.181
In Reply to: RE: Ars Technica dissects an AudioQuest Vodka ethernet cable posted by Jaundiced Ear on July 23, 2015 at 22:01:41
It's interesting that a couple folks (in the comments after the article) called this cable out for not being CAT7 at all.Yes, you can buy cables on Amazon and else where that are advertised as "CAT7" but to meet CAT7 specs the cable cannot use RJ45 style connectors. And CAT7 is not recognized by the Telecommunications Industry Association (TIA) which DOES recognize CAT6, CAT5, etc. CAT7 is essentially DOA. And seeing those photos of how this cable is terminated to the connector makes me wonder if the thing even meets CAT6 specification.
None of this matters though as no one needs CAT7 or even CAT6 for the speeds and distances required in home networking at audio data rates.... even 'hi-res' audio data rates. However, I'm sure we can speculate to death about shielding, EMI, RFI, etc.
AND.... I am certain that some will 'hear' the benefits of CAT7 cables from AudioQuest and others. ;-)
Edits: 07/24/15Follow Ups:
CAT7 is a proposed spec. It isn't "DOA" nor is it in early stages. It is an incremental improvement above Cat-6a, and adds screened-shielding over the entire cable, and calls out double shielding on each twisted pair. This was done for 2 reasons: reduce crosstalk further, and make it immune from "alien crosstalk" (meaning RFI). It also is suitable for routing near noise sensitive equipment, if you can't avoid the cable routing altogether.
Where CAT7 has a weakness, if you do not connect the shields to the shield on the GG45 connector you might drop to Cat-6 for datarate and throughput. Given the GG45 is not compatible with RJ45, and there is little gear that accepts GG45, it is no wonder that every cable maker out there has been producing a "RJ45" compatible pseudo-CAT7 cable. Thae main thing is the shielding.
So while this cables might not meet the self crosstalk spec of true CAT7, it will meet the RFI/EMI specification, which in a home networking environment is probably more important considering both Cat-6a and Cat-7 have similar bandwidths (500MHz vs 600MHz) and datarates.
So far a CAT choice ... if you are running cables near your audio gear, you would probably do better to choose a pseudo-Cat-7 cable than anything else.
But having said that, since Cat-7 isn't an official standard, it is unlikely cost conscious makers will be meeting the spirit of the spec with the only giveups being the RJ45 compatibility. If my experience with Cat-5e and Cat-6 is a guide, they probably vary all over the map.
I expect that Audioquest hasn't skimped on anything in this range -- and their whole ethernet range from the Pearls to the Diamonds will meet this standard and then go on up from there. And from $7-9/foot - $hundreds/foot you will be paying a premium over no-name, but you do know what you will be getting. And given a typical "audiophile" stereo is about $5k, adding a network connections using at least the low end Pearls for the noise reduction, will likely be money well spent all told. Or if you are handly, learn how to terminate ethernet cables and roll your own. It isn't that hard.
============================
As audiophiles, we take what's obsolete, make it beautiful, and keep it forever.
Hey! I have a blog now: http://mancave-stereo.blogspot.com or "like" us at https://www.facebook.com/mancave.stereo
You try to pass your self off as an authority, but I suggest you do some fact checking.
RJ45 connectors are absolutely ok for CAT7 cable. The CG45 or Tera connector are RECOMMENDED by the TIA.
Please clarify what you mean that CAT7 is not recognized by the TIA?
If I am wrong, provide evidence.
And for the record, I have been calling out AQ for their so called "Cat7" cable for a year now.
I'm not a networking authority but it's not uncommon knowledge.RJ45 connectors are fine for CAT7 cables if you wish to only achieve CAT6A specs. CAT7 is pretty much a non starter as we wait on CAT8. CAT7 is not even recognized by the TIA/EIA. Look it up. It's not hard to find... or maybe it is because they don't officially recognize it!
Don't get the cable type mixed up with meeting a spec. CAT7/7A cable with RJ45 connectors do not meet CAT7/7A specs.
Basically CAT7 is a solution looking for a problem and promoted by cable makers.
CAT6a is perfectly suited for 10GBASE-T per Cisco and others but not suited for 40GBASE-T (the next step), and CAT7 doesn't cut it for 40GBASE-T.
So, CAT7/7a is caught in between so to speak. It's not needed for 10GBASE-T and it doesn't cut it for 40GBASE-T and beyond.
And IMHO, none of this even matters in the world of home networking for audiophile applications. Plain ole CAT5E (or CAT6A if you must) is MORE than sufficient.
Edits: 07/24/15
Very interesting...
As I understand it, it is the RJ45 connector that does not meet spec.
Speculating: could it be the pin configuration causing a problem with cross-talk?
From what I understand, the non-RJ45 connector for CAT7 does meet spec. Manufacturers are supplying adapters to female RJ45 ports.
What I am curious about, besides exactly why it doesn't meet spec, is how is CAT8 with RJ45 termination going to meet a spec that is even higher in bandwidth?
"Asylums with doors open wide,
Where people had paid to see inside,
For entertainment they watch his body twist
Behind his eyes he says, 'I still exist.'"
...how is CAT8 with RJ45 termination going to meet a spec that is even higher in bandwidth?"
A couple ideas come to mind.
- The CAT8 specs calls for a shorter maximum distance so that helps a lot.
- New manufacturing techniques with tighter tolerances in terminating the connector to the cable.... techniques that will be impractical to impossible to achieve in hand soldered boutique cables.
Nice written article.
"Propagation Delay & Delay Skew""Propagation delay is the amount of time that passes between when a signal is transmitted and when it is received at the opposite end of a cabling channel. The effect is akin to the delay in time between when lightning strikes and thunder is heard - except that electrical signals travel much faster than sound. Delay skew is the difference between the arrival times of the pair with the least delay and the pair with the most delay. Transmission errors that are associated with excessive delay and delay skew include increased jitter and bit error rates."
For what it's worth and it could be nothing, note the specified 'delay skew' is about half for CAT 7 (30ns) as that for CAT 6/6a (50ns).
Edits: 07/25/15
Thanks for the detail and the overview.
There is more to the story, but you provide generally accurate info I believe.
The TIA was not able to agree on standards, and there was of course differing agendas and politics involved. Cat7 has been adopted happily by industry for mission critical applications and is quite standard in data centers.
But yes, supposedly Cat8 is next.
But to be clear, the technical benefits of Cat7 are there...superior noise rejection, higher bandwidth and much better connectors.
"But to be clear, the technical benefits of Cat7 are there...superior noise rejection, higher bandwidth and much better connectors."
True, and I have found them an improvement most likely due to the shielding. I use good CAT7 for audio, not boutique ones.
As I have posted before, Rosewill, at a buck a foot, is all you will ever need unless you are a NASA rocket scientist.
I see the part time guy got his stuff deleted. lol
Yes, it seems so. Ran to his mommy?
Your assessment of his so called review was spot on. This type of fictional nonsense must be called out.
Yes... There is no way a network could perform as badly as he initially claims unless the cables were wrapped around fluorescent lights!
It's hilarious his network has dropouts and glitches and then the HQ cables ride in on a white horse to save the day. LOL
The funniest part is he claims to be an "IT professional" yet still had the gaul to publish such crap.
Edits: 07/25/15
yes, and his assertion that there was a colossal difference between networked and locally stored files shows his knowledge of how to set up a computer audio system is non existent.
Having read some of his other computer audio related reviews, this is obvious.
I posted something over on Critics. What do you think?
Edits: 07/25/15
Nice! i will comment.
"As of November 2010, all manufacturers of active equipment have chosen to support the 8P8C for their 10 Gigabit Ethernet products on copper and not the GG45, ARJ45, or TERA in order to function on Cat 6A.
Category 7 is not recognized by the TIA/EIA."
from wiki
I found that $300 is my threshold for positive differences in sound for wire. So basically you can put some nice braid on a lamp cord price it at $350 and I'll be dammed it sounds great!
:-)
Dynobots Audio
Music is the Bridge between Heaven and Earth - 音楽は天国と地球のかけ橋
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: