2. cables
  3. 195218-198226

How can different CAT5/6 cables affect sound.

While is is beyond doubt that analog cables affect sound quality and SPDIF, TOSlink and AES/EBU can effect SQ, depending on the buffering and clocking of the DAC, I am at a loss to find an explanation for how different CAT5 cables can affect the sound.

The signals over cat5 are transmitted using the TCP protocol.  This protocol is error correcting, each packet contains a header with a checksum.  If the receiver gets the same checksum then it acknowledges the packet.  If no acknowledgement is received in the timeout interval the sender resends the packet.  Packets may be received out of order and the receiver must correctly sequence the packets.

Thus, unless the cable is hopeless (in which case nothing works) the receiver has an exact copy of the data sent from the sender, AND there is NO timing information associated with TCP. The receiver must then be dependent on its internal clock for timing. 

That is different with SPDIF, clocking data is included in the stream, that is why sources (e.g. high end Aurenders) have very accurate and low jitter OCXO clocks and can sound better then USB connections into DACs with less precise clocks.

Am I missing something as many people hear differences with different patch cords?

retiredaudioguy
cleeds
6,323 posts
 

richardbrand

... By the way, TCP is not "Standard" Internet Protocol, it is one of two widely used protocols ...

There are many internet protocols. TCP/IP - which is the protocol used by services such as Qobuz and Tidal - deliver bit perfect data to your streamer. It is as simple as that. I’m not sure why you use so many words to claim something different.

The sender can tell when packets go missing, and resend them.  All this can take several seconds and if the packets are being consumed as a stream, lead to dropouts ...

That would suggest a problem with the network. As everyone knows, the stream is fed into a buffer and many minutes of music can be sent, verified as bit perfect accurate, and stored in the buffer in a matter of seconds. Literally. So even a pretty wonky network is capable of delivering bit-perfect data to your streamer pretty much every single time.

TCP is not bit-prefect if, for example, the network goes down halfway through a stream. 

What’s your point? A CD player with a broken laser won’t work. A turntable with a fried motor won’t work. A car with no gasoline won’t work. Broken things don’t work.

elliottbnewcombjr
6,071 posts
 

"If it works, it's a Fluke" Excellent

zlone
996 posts
 

In most networks you are receiving all of the data and it is bit perfect. And if your service is using TCP, not IP, then it is for sure bit perfect. But that is not the big issue, noise is the big issue. If CAT 6 offered perfect shielding, then there wouldn’t be CAT 8. My system sounded great with a 30’ BJC cable, until I replaced it with optical. You don’t notice the noise until it’s gone, and thus begins your cable journey. 

retiredaudioguy OP
100 posts
 

If noise, picked up by non-shielded Cat5 cables is the problem, and from responses it seems that is might well be the issue, would that argue that a Wi-Fi (and thus decoupled) connection would work best?

I cannot personally comment on this as I rarely listen to streaming sources on my big rig (I hate to say reference system) and it does not support Wi-Fi anyway, and my 2nd system has only Wi-Fi capability.

My wife is a wonderful supporter of my high end journey (she supported my upgrade from a K-01xs to the xd) but would probably be critical of a 30 foot cable draped around the room from my WAP/Switch to the Bluesound node - but I might try it one day when she is out at the gym as I have a Cat5 cable building kit. 

The actual transfer of the bits seems unlikely to be the issue as the highest bit rate for streaming would appear to be 18.423 Mbps  (2*192k*24*2) (two channels*sample rate*bit depth*2 for the TCP and other overhead) and the Cat5 standard is for 100Mbps.

 

sns
4,152 posts
 

This is curious, optical reportedly superior to LAN cable, this my experience as well. So some will say this imagination, others will trust their senses. And then we have reports the transceivers in these optical devices don't all sound alike. Now we also have reports managed audiophile switches provide superior sound via decreasing network traffic. This all very curious, networks have impact on sound quality, networks have no impact on sound quality, take your pick. I suspect this thread could carry on and on with no conclusive evidence on either side, this thread will not provide the final word.

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