Audio Cable used for CAT 5 /6?

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Newmarket

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You could use two stretched out coat hangers wrapped in electrical tape as speaker wire, and it would work, barley. But would you?

Actually that would likely work very well. Obviously I'm assuming metal coat hangers. Those wooden / plastic ones would be rubbish :ROFLMAO:
You'll be saying they don't work as car radio aerials next ! Austin Allegro, coat hanger aerial, Radio 1 on Medium Wave. Classic.
(This may be a bit UK specific :))
 

Newmarket

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AES/EBU cable is not quite the same as balanced audio cable. AES cable is built to different specifications. AES cable can carry analog audio as well as (if not better than) balanced audio cable. On the two web pages below, note the cable capacitance (in picofarads per meter) and that the capacitance of the analog cable is about 4 times as much as the capacitance of the digital cable. The higher capacitance of the analog cable degrades the HF response of the digital signal to the point where it is unusable in a much shorter distance. Also note that the twist on the digital cable is almost twice as tight as on the analog cable.

Analog cable (StarQuad)

Digital cable (AES/EBU)

yeah - but StarQuad configured cable is exactly the audio cable type you'd want to avoid for data transmission due to its higher capacitance cf standard twisted pair audio cable types.
 

Newmarket

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That's valid for 44/16 and maybe 44/24. Remember that early 24/96 systems used two cable runs? My ancient converters still support both specs. I haven't run the numbers but I'd assume 24/96 over a standard mic cable wouldn't work very well.
44/16 or 44/24 - makes no difference - the data / bit rate is the same with same number of bits.
In reality the RS422/485 receivers now (and for a long time past) available do a great job in terms of data recovery even with severely impaired data eye-patterns.
I recall that even IEC950 (spdif) transmission can be robust through reels of 'ordinary' unbalanced cable in terms of bit error. Far beyond its published spec'.
Cable/Data induced jitter is another issue but not really an issue if you are reclocking or simply moving data.
Physics says that things will be tougher at higher sampling rates but it won't 'fall off a cliff'.
 

Gold

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I'm lazy too... so I leave it up to the OP to try the limits of the system.

All the more reason to validate by experiment.
I have a roll of Belden Mediatwist I use when the connector is a dSub. I have a roll of Belden 1800B I use when the connector is an xlr. If it works I’m done. When the connector is a phono plug I use RG59. For both analog and digital. That’s a non standard cable I know works from experience.
 

abbey road d enfer

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When the connector is a phono plug I use RG59. For both analog and digital. That’s a non standard cable I know works from experience.
No wonder. RG59 is a low-loss RF cable, with only 3dB attenuation at 10MHz per 100m. S/PDIF 24/96 is 9Mhz.

EDIT: I didn't push the right buttons, 24/96 is about 12MHz. Not that it matters much for RG58.
 
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moamps

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IIRC,
S/PDIF uses a biphase mark code where the clock frequency is twice the bit rate. The clock frequency is the highest possible frequency in transmission so it determines the bandwidth.
The word is always large 32 bits so we can calculate
16/44 ---- 44100 * 32 * 2 = 2.8Mbps ---- BW = 5.6MHz
24/96 ---- 96000 * 32 * 2 = 6.1Mbps ---- BW = 12.2MHz

Why the word is 32bit? Because in addition to digitized audio information, there are additional codes for synchronization and protection.
 

moamps

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Are you kidding me?
I gave simple and concise information in my post 47 about the bandwidth that takes up the s/pdif signal. Anyone who wants to know more can easily ask Google what the biphase mark code means.

No wonder. RG59 is a low-loss RF cable, with only 3dB attenuation at 10MHz per 100m. S/PDIF 24/96 is 9Mhz.

EDIT: I didn't push the right buttons, 24/96 is about 12MHz. Not that it matters much for RG58.

You should not use a slippery keyboard. RG58 is 50ohms cable.
 

Gold

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You should not use a slippery keyboard. RG58 is 50ohms cable.
I use RG58 primarily because it has a thin OD and easily fits in phono connectors. I also use it on the bench to patch BNC connections like on an oscilloscope and other instruments. Also seems to work okay.

I’ve also found that for BNC connectors it pays to settle on a specific brand and type of cable because getting a connector to fit a cable can be an exercise in frustration. I also use BNC connectors for unbalanced analog audio on my builds for my use.
 

moamps

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I use RG58 primarily because it has a thin OD and easily fits in phono connectors. I also use it on the bench to patch BNC connections like on an oscilloscope and other instruments. Also seems to work okay.

I’ve also found that for BNC connectors it pays to settle on a specific brand and type of cable because getting a connector to fit a cable can be an exercise in frustration. I also use BNC connectors for unbalanced analog audio on my builds for my use.
Oscilloscopes and measuring instruments use mostly 50ohms connectors so I also use a set of 50 ohm cables for my measurements. I know how PITA can be to mount BNC connectors on cables. When I was a lot younger, I worked on wiring a few TV stations in RGB mode so I hated the crimp tool. Many do not know this but there is a significant difference in the mechanical design of BNC male and female connectors for 50 and 75 ohm characteristic impedance. And they should not be misused. I say this only so that this would not turn out to be just a one-to-one conversation as Abbey has already objected to me ;).
 

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moamps

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Maybe an eye-opener?

They say:
"If you hook them up with UTP, unshielded twisted pair Category 5e or 6, they work just fine but there is no ground connection. For self-powered or dynamic microphones this is just fine."

I pretty much disagree. The metal housing of the dynamic microphones should be grounded too. I would never use unshielded network cables for audio, especially for microphone levels.
 

Gold

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Many do not know this but there is a significant difference in the mechanical design of BNC male and female connectors for 50 and 75 ohm characteristic impedance.
I didn't know this. The way I now order coaxial/BNC cable is to pick the cable and then use a recommended connector. Then cross check that the dies I have for the crimp tool will work. The supply houses usually include that information. I guess I should double check.
 

abbey road d enfer

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I didn't know this. The way I now order coaxial/BNC cable is to pick the cable and then use a recommended connector. Then cross check that the dies I have for the crimp tool will work. The supply houses usually include that information. I guess I should double check.
For most audio applications and measurements, impedance mismatch will not matter. Just think how the typical oscilloscope probe, that uses 50 ohm BNC connectors, connects to a 1 Megohm input.
 

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