Noise by wire

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USLatin

Panamaniac
sorry, I meant noi>S<e, not noice

Is is extremely likely that the cheap ($20) RCA to Phono 49 ft. wire I bought from a random computer componerts type website is responsible for a hughe amount of noice? I am using it as my Tape Return from the RCAs on my HVX to my MixPre... I quickly unplugged the headphones and plugged them into the HVX to hear a MUCH cleaner sound...
If it matters I have the 50ft. XLR that I am planning on taping together with the RCA - Phono 49ft. cheapo cable going into the HVX. Also, a 30ft. XLR to a 1.5ft. XLT comming from the microphone to the MixPre. And all of these wires were tangled up on top of eachother...

Should I tape them together or get a better wire/s?
 
I wouldn't use an unbanlanced cable for lenths over 10' if I could help it, so if you need the length I'd get a better (meaning balanced) cable. A coiled, unbalanced cord is about as bad as you can get for EM interference.
 
ouch! double ouch...
First ouch for my back from taping the whole thing, just finished...
Secound ouch is from what you just said... so what exactly is a "balanced" cable?

I guess I'll use this one just so the boom op can tell if the camera is recording and he can monitor the ourput of the MixPre for sound quality...

Should I use my better headpnones on the camera then? I'd rather delegate that duty to the boom op. so I can focus on the image... my second pair is a cheap one...
 
A balanced cable has:

+

-

shield (grounding)

Positive voltage signal, negative voltage signal, and shield. It's called "balanced" because the signal voltage is balanced "out of phase" by this configuration. This means that any noise or interferrence is seen equally on both + and - parts of the circuit and therefor it's ignored... the end circuit only reacts to voltage changes caused by the connected gear.

You should see an XLR plug or a TRS connector (1/4" or 1/8") for a cable to be balanced... but seeing those connectors is no guarantee... the circuit must be balanced entirely... meaning that you could take an XLR or TRS and solder it so that it's NOT balanced... but let's say you have a DVX... and you run an XLR mic via an XLR cable into the DVX mic input... that is a balanced circuit.

Simple no?
 
that went 40% over my head, but thank you...
I will have the boom op use the output of the MixPre as the monitoring signal and use the Tape return just to check that the camera is recording and that both left and right are being recorded... then I'll have the better headphones on the camera monitoring the audio...
I'll sit down and re-tape a new snake when I can afford to get a second 50ft. XLR and a 50ft. balanced RCA to phono with the extra plug thingy for the second pair of headphones to be plugged in by the camera... any ideas of where to get such a cable?
 
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check different cable that goes directly from the hvx headphones to mix pre return - if it better , the output of the hvx is noisy
the return amp on mix pre adds aditional noise as well , you may be in the adge of it so it adds self noise .
 
A balanced cable won't really help unless you connect it to balanced gear at both ends... and RCA's aren't balanced.

You're sending a line level signal, and, frankly, in most situations I wouldn't expect a "huge" amount of noise from your described configuration. Can you describe the noise a little more? And, is it constant, or does it change as you move the cables around? If it's really outside interference, you'll almost certainly hear the soiund change as you move things (much like moving an antenna around). You may have some kind of grounding issue instead, which would be my first guess for "huge" amounts of noise here....

Actually, I thought you were going RCA to RCA - but an 1/8" mini plug- ugh! Those are prone tro problems, especially cheap ones that don't fit precisely. So, add to the above - if wiggling the 1/8" plug (not the cable) makes a big difference in the noise, then it probably isn't making proper contact and that may be the whole problem.
 
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Oleg 2 said:
check different cable that goes directly from the hvx headphones to mix pre return - if it better , the output of the hvx is noisy
the return amp on mix pre adds aditional noise as well , you may be in the adge of it so it adds self noise .
Click to expand...

can someone point me to a site where I could learn how to re-wire the RCA end of the cable to fit it with a phono tip? I would greatly appreciate it
 
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