Deleted
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Post by Deleted on Sept 23, 2013 22:43:06 GMT
Before I bought anything for my Streaming Journey, I thoroughly researched it. I knew about Cat 5 and 6 cables and wondered which would have advantages (if any) for the particular job I would employ them in, namely streaming audio. In my travels I came across this and thought I would post it for a bit of fun, as it made me laugh out loud when I came across it. If I asked you to buy 75 cm of ethernet cable for nearly $600, almost £380, would you buy it?? Of course you would, because you're an idiot. At least, that must be what Audioquest thinks WARNING FRANS, SIT DOWNAudioquest Ethernet Cables
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solderdude
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Post by solderdude on Sept 24, 2013 4:25:29 GMT
Cat 6 is great for long Gbit networks in buildings. Especially when bundles of these cables run alongside each other in ducts over long distances.
I am quite certain though that those that install kilometers of that stuff in buildings won't be buying bulk from audioquest for some obscure reason.
The sheaths and plugs look very nice though ! To some that alone may be worth the price
Their 'Forest ($29/.75m)' seems to be affordable and am willing to bet sells like hot cakes.
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Javier
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Post by Javier on Sept 24, 2013 7:48:55 GMT
CAT6 is so " passé"... for optimum SQ CAT7a or even CAT8 will be best
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solderdude
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Post by solderdude on Sept 24, 2013 8:19:24 GMT
let's have a look if you are correct there. 24 bit 'steps' are coarse... yuck, at least 32 bit is needed and there are DAC chips of just a few $ that support that already... wait let's build in a safety margin and go for 64 bits. I am quite confident one day we will be able to beat the noise floor and in that case we already have the 64 bit format. Now, honestly... acc. to some we can easily hear up to 100kHz and before we have drivers (tweeters/headphones) that can make this audible we must have a format that samples that 100kHz at least 10 times so we can describe the 100kHz more accurately.... we have to for audio SQ sake. We need to be able to 'describe' a needle pulse of 5us accurately so really need that sample frequency. The rather slow 384kHz sample frequency cannot do that and even 768kHz is a bit on the meagre side. Nah... besides the 64 bits we thus need at least 1MHz sample frequency so lets make it 1,536kHz/64 bits. For stereo we need at least 200 Mhz bandwidth to transport this format. CAT5 can handle max 100MHz so way to slow for real audio, CAT6 is capable of merely 400MHz which would just be enough. We don't want jitter and a bad slew rate in our digital, yet analog transported signals though.. so CAT6 may indeed be a bit on the slow side. CAT7 does 625MHz and CAT8 is capable of transporting of up to 1400MHz. Fortunately, as we want to have a safety margin of at least a factor 10 the 1.4GHz bandwith will just do for our new audio format. So YES we DO need CAT8.... Now.. we must persuade Audioquest to make a nice sheath and box for it as well as gold plated titanium alloy connectors and we can finally enjoy audio. Yuck .... 24/384 NOBODY can enjoy such an outdated format can they ? Javier, will your upcoming DAC be supporting this format as well, that would be nice ? That should be enough for most audiophools.
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Javier
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Post by Javier on Sept 24, 2013 8:41:23 GMT
Well.... the ESS Sabres can accept up to 32/1.536MHz in external processing mode, if I could persuade Amanero to modify his board to accept that format we could get close though, he is already working on adding 705.6/768K, unfortunately the 64bit thingy would be a little trickyer, at least until some manufacturer comes up with the necessary chip. How about doing it with discrete components? a 64bit R2R ladder DAC using SMD resistors? Wonder what kind of accuracy/tolerance will be needed for the resistors....
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solderdude
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Post by solderdude on Sept 24, 2013 8:46:57 GMT
How about doing it with discrete components? a 64bit R2R ladder DAC using SMD resistors? Wonder what kind of accuracy/tolerance will be needed for the resistors.... 0.000000000000000000001% roughly (give or take a few zeros) I think Farnell sells some, they are not even that expensive.
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Javier
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Post by Javier on Sept 24, 2013 8:55:36 GMT
only 0.000000000000000000001% ?? Piece of cake then!!
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Dave
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Post by Dave on Sept 24, 2013 9:23:48 GMT
Sorry for the numptie question again but, as a chain is only as strong as it's weakest link, do normal 'Gigabit' modems and switches bring the performance down to 'normal' levels? - i.e. negate some or all of the benefits of the faster CAT 7 or CAT 8 cable? TIA, Dave.
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Javier
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Post by Javier on Sept 24, 2013 9:28:15 GMT
Do you want a "real world" answer or an audiophile one?
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solderdude
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Post by solderdude on Sept 24, 2013 9:46:11 GMT
the type of cable is only of real importance for LONG networks where cables are closely tied together.
Each 'bit' of an R2R ladder network has to be EXCACTLY double the value of 'next' bit. So the biggest resistor vale will have to be the exact same value as all the other 63 bit resistance values added. As the biggest resistor value is 9223372036854775808 x bigger than the smallest value it would have to be extremely accurate otherwise you would not reach an ENOB of 64 bits providing a noise level that low (-380dB) would actually be possible. Would love to see amplifiers perform that well and would need to have 0.000000000000000000something distortion.
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Dave
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Post by Dave on Sept 24, 2013 10:14:39 GMT
Do you want a "real world" answer or an audiophile one? You should know me Javier, give it to me as it is, I'm a big boy now, I can take it . On the other hand it would be interesting to see 'both sides of the 'coin'' so I am better advised. Always ready to learn, I just wish more of it would 'stick' . @ Frans, Not sure I fully understand your response, particularly the numbers and the calculations behind them, but I think the one word answer is "No" ? .
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Javier
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Post by Javier on Sept 24, 2013 10:28:37 GMT
Would love to see amplifiers perform that well and would need to have 0.000000000000000000something distortion. Remember many audiophiles can hear noise at lower than -150dB.... and anyway, it is not about numbers ("we don't listen to graphs or numbers") is about how it sounds and surely 64bit has to be better than 32bit, right?
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solderdude
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Post by solderdude on Sept 24, 2013 10:45:22 GMT
I am still amazed some people make that claim to hear -150dB or 'suspect' it may be in that area. I guess this is mostly because the differences they hear must be explainable and as there are measurable differences around these values in the best DAC's this MUST be it.
Here comes the good part though....
dB's can be used with other dB's as it is a relative number. We all know 120dB is very loud (pain level) and 0dB is absolute quiet (well -7dB for certain frequencies in absolute quiet conditions and only after being a while in an acoustic 'dead' chamber) So to hear a S/N ratio of -130dB you need a peak in the SPL well over the pain treshold.
The ears can't handle that though, the 'automatic gain control muscle' in our ears kick in much sooner reducing the dynamic range. Those who have visited a loud concert or disco may have experienced this.
Our 'practical' dynamic range is about 70 to 80dBb so numbers with bigger distances cannot be heard, regardles how often it is stated they can.
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Javier
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Post by Javier on Sept 24, 2013 13:01:49 GMT
You should know me Javier, give it to me as it is, I'm a big boy now, I can take it . On the other hand it would be interesting to see 'both sides of the 'coin'' so I am better advised. Always ready to learn, I just wish more of it would 'stick' . In a Gigabit "home" network even CAT6 is already overkill. For many years I've used CAT5 and CAT5e for Gigabit enterprise networks and had no problems whatsoever. No dropped packets, no collisions, no fragmentation, no nothing, even when hitting max throughput in a sustained way. Nowadays the cost is almost the same for CAT6 so it'll make sense in a new installation. Higher than CAT6 could make sense in complex 10Gbps or 40Gbps systems but not anywhere else except maybe in the audiophile world, preferably from a cable specialist and with a hefty price tag. Goggle for Denon Link and be amazed what they can charge for a run of the mill CAT5 patch cord worth a couple of quid, but who knows... maybe they treated it with some kind of fairy dust that provides magical properties that scientists, engineers and other "bits are bits" close minded people cannot understand, measure or hear.
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gommer
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Post by gommer on Sept 24, 2013 13:27:32 GMT
Dave, until recently I exclusively used Cat5e as it's adequate for all duties. But since I've found a cheap source for good Cat6 cables, I've switched to using Cat6. Comes in handy when 10Gbit becomes a common consumer technology.
Cheers, Marc
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