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$10K Ethernet Cable Claims Audio Fidelity, If You're Stupid Enough To Buy It
MojoKid writes: There are few markets that are quite as loaded-up with "snake oil" products as the audio/video arena. You may have immediately thought of "Monster" cables as one of the most infamous offenders. But believe it or not, there are some vendors that push the envelope so far that Monster's $100 HDMI cables sound like a bargain by comparison. Take AudioQuest's high-end Ethernet cable, for example. Called "Diamond," AudioQuest is promising the world with this $10,500 Ethernet cable. If you, for some reason, believe that an Ethernet cable is completely irrelevant for audio, guess again. In addition to promises about the purity and smoothness of the silver conductors, and their custom "Noise-Dissipation System," they say," "Another upgrade with Diamond is a complete plug redesign, opting for an ultra-performance RJ45 connector made from silver with tabs that are virtually unbreakable. The plug comes with added strain relief and firmly lock into place ensuring no critical data is lost." Unfortunately, in this case, there's the issue of digital data being, well... digital. But hey, a 1 or a 0 could arrive at its destination so much cleaner, right?
ask an ye shall recieve: http://www.the-ear.net/review-...
Actually no, on the Ethernet side of things this is the most expensive cable.
Sure there are more expensive audio cables, but they at least make claims which sound believable for the true idiot, but ethernet is a packet transfer system with error correction. There's simply no amount of fancy words to describe how technologically a cable could be the difference.
In the audio chain people talk about sound waves affected by the cable.
In the digital audio chain people talk about jitter, temporally accurate rising and falling pulses, and transmission lines.
In the power supply side people talk about shielding and noise from the power grid.
But this is a system which inherently transfers data from one side to the other, checks it along the way, and then stores it on the far side in preparation for being played. There's only so much garbage to be made up.
Sorry, but you're wrong. Audio CD's use reed-solomon ECC, and it's the reason why a little speck of dust or small scratch doesn't affect the audio.
There are two things called jitter here. When you're ripping a CD, sometimes audio reads will not give you the same block on the disc each time you ask for it. Older ripping programs had to read multiple times to correct that. Newer drives support "Accurate Stream", which makes this sort of jitter go away altogether.
CD transports do not have this problem. CD read jitter only happens if you're trying to read audio CDs at the block level, something they weren't really designed to do. A regular CD player will not do this.
The second type is transport clock jitter. The digital interface between CD transports and DACs doesn't have a separate clock. It's derived from the data itself. That process wasn't always perfect. In the mid 90's, the recovered clock was sloppy enough that bad ones were audible. Stereophile did a useful article measuring cd transport jitter during that era.
Nowadays the clocks and clock recovery circuits are so much better, I'm skeptical this is a real issue anymore. And most computer audio players buffer their data and then generate their own clock, which completely eliminates transport jitter.
Just a note of perspective. It is easy to tag audiophiles as naive fools with too more money than sense.
But not all are like that.
I am quite interested in good rendering of favourite music, so are a few friends. We do indeed try out hifi gear, but that doesn't mean we all fall for this snake oil product.
By and large most people are used to the sound of multimedia speakers or mini systems. For a music lover, it is possible to get so much better results, and it does not need to cost crazy money on crazy products for a decent result.
So far I find speakers having the largest influence on the end reproduction quality. There is some difference between the electronics, but once you are beyond the bare basic level the differences are getting smaller. But speakers are worth spending money on if you are a music lover using a good quality music source.
There is no error correction on audio CD.
Yes there is. It uses a dual interleave Reed-Solomon code together with 8-14 modulation and three joining bits.
192 data bits are encoded in 588 bits on the CD.
Those 588 bits comprise:
24 bits sync word plus 3 merge bits. (27 bits)
33 EFM words of data of 14 bits plus 3 merge bits per word (561 bits)
The 33 bytes of data are:
24 bytes of audio (12x16 bit samples)
8 bytes of parity.
1 byte (8 bits) of subcode information.
The merge bits allow the min/max separation of 1s to be maintained between EFM codewords and also allow the data to be DC free
God said, "div D = rho, div B = 0, curl E = -@B/@t, curl H = J + @D/@t," and there was light.
I spoke to a friend who is in ultra-high-end business about those cd transports and how can one sound better than the other (he's not stupid) and after a while we came to the conclusion (well I did anyway, he knew this) that it all boils down to jitter and real-time error correction.
Much of the time, the perceived improvements in high end audio electronics (not including speakers and other acoustic devices) boil down to volume differences, and the imagination of the listener, which is fueled by clever marketing and obsessive-compulsive worrying about imperfect audio.
Even nowdays if you wish to rip a cd that's as clean as possible you have to do multipass read with that german free software I forgot what it's called now.
Actually, if there are no problems with the disk or the drive, one can often just copy the audio tracks at full speed with no software error correction, and the result will be binary identical to that of the slow multipass read. The latter is at least still somewhat useful to confirm the lack of errors, although that could also be done with an online database of checksums. The last CD-ROM drive I had that definitely needed jitter correction was bought in the late 1990's.
I believe silver wire ethernet cable will be better and super quality rj45 will contribute in some miniscule way to fewer error corrections on layer 1, bit $10k worth? Don't think so.
If the cheap network cable cannot be used to transmit audio reliably, then it would also have issues with other types of data. The playback is also buffered (which it needs to be in any case, even in a hardware player, as the data is sent in packets), and as long as the buffer does not underrun, there should be no issues with the audio quality even if the occasional packet needs to be sent again because of errors. When the buffer does underrun, it causes skips, stutters, pops, and other obvious distortions in the audio, rather than subtle changes in the tonal balance, sound stage, or whatever. There could be dropped packets if the protocol used does not support re-sending them, but that produces similar audible effects to those of buffer underruns.
You can do one of 2 things.
1. You can have a precision spin mechanism that ensures a constant transfer rate.
2. You can have a flimst plastic spin mechanism and a nice big data buffer.
Guess which one you're more likely to find in a cheap CD player.
A precise spin might help if you want to minimize buffering delays, but it's questionable.
CDs aren't precision-balanced, so there's only so far that you can go on the spin mechanism without using a relatively massive flywheel. Which will have a spin-up delay.
Once the buffer is loaded, the unloading process is controlled by a megahertz timing source, and I defy any audiophile to hear jitter in that.
A letter in a hi-fi magazine (Hi-Fi News and Record Review, but I'm not 100% sure) years ago from someone who was upgrading his system.
He started by describing the upgrades to the cables and connectors. Then moved onto rewiring the amp with better quality conductors. Rewiring his house for a better electrical feed into the kit. He then described chasing his dream of perfect audio further by liaising with his local power company to get the substation upgraded. Finally (the punchline) was that he had written to the power generation company to change the isotope of uranium they used to get better bass.
Made me giggle.
Gold is a worse conductor than copper and silver. Its only benefit is that it does not corrode. Silver is superior to copper in just about every way.
The ultimate conductor (if you wanted to pretend that errors come from resistance, rather than RFI) would be gold-coated-silver, I believe.
You know just enough to be dangerous. You're also wrong. Each pair in a Cat 6 cable has a different rate of twist. That's done to reduce crosstalk between the pairs. I often use short (<10 M) Cat 5 patch cables for temporary 1G connections without issue, Cat 6 becomes more important when you're bundling cables together and using longer lengths (100 M max). Regardless, any errors which occur can be recognized and recorded, so any difference between cables could be easily and objectively quantified - no need for subjective "the soundstage immediately opened up" BS.
The length of different pairs due to the difference in twists is insignificantly different.
You then go on to confuse matters by comparing 1G Ethernet to HDMI to I2S, three completely different things, with different signalling at different rates. 1G Ethernet runs at a clock rate of 125 MHz, encoding 8 bits per baud. HDMI 1.3 has a maximum clock rate of 340 MHz, making transmission line length more critical.
I2S does NOT have 3 clocks as you claim. It has a single clock, a word select signal (used to indicate whether left or right channel info is currently being sent, sometimes called the "word clock," even though it changes synchronously with the bit clock), and a data signal. Used for standard CD audio, it has a clock rate of less than 1.5 MHz. Even with newer "high definition" audio formats, the clock rate is still significantly less than either 1G Ethernet or HDMI. It tops out around 12 MHz for 32 bit stereo at 192 KHz. For more channels, additional data lines are added. But, transmission line length is not as critical as for either Ethernet or HDMI, which run at 10x+ the speed of I2S. 1/2 cycle of a 12 MHz clock is almost 50 feet long on a wire. A length difference of fractions of an inch simply doesn't matter.
"National Security is the chief cause of national insecurity." - Celine's First Law
Sorry, selling that stuff as it is advertised is: fraud.
Making a sound review in a magazine based on physics that are wrong is even more fraudulent.
Fraud is a felony. Felony means the prosecutor goes after the violator as soon as he is aware of the topic. No special action of citizens required.
Calling that a nanny state is just retarded, sorry.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.