Installs Snake Issues

I'm having problems with my copper snake. Channel 1 (send) only functions well with a condenser mic and phantom power. A dynamic mic comes in very degraded and at low volume. My cable tester shows good continuity on all 3 conductors, but of course that doesn't guarantee signal quality. It's a 250' 32 pair with a box at one end and a Whirlwind Mass to XLR/TRS breakout at the other. Channel setup is 24 sends, 7 returns, and a DMX line.

This snake sits in an underground outdoor conduit year round. The pipe diameter and number of turns make pulling it out in the off-season impractical/damn near impossible. It just received the breakout end upgrade due to water damage at the FOH end that affected several channels. Now the Mass connector lives in a custom PVC capsule with dessicant packets between performances.

My theory is that this particular channel simply absorbed water farther into the jacket. However I cut back as much as I could given its fixed path in the ground.

Can anyone think of another cause that I might be overlooking? Or am I just SOL?
 
I'm having problems with my copper snake. Channel 1 (send) only functions well with a condenser mic and phantom power. A dynamic mic comes in very degraded and at low volume. My cable tester shows good continuity on all 3 conductors, but of course that doesn't guarantee signal quality. It's a 250' 32 pair with a box at one end and a Whirlwind Mass to XLR/TRS breakout at the other. Channel setup is 24 sends, 7 returns, and a DMX line.

This snake sits in an underground outdoor conduit year round. The pipe diameter and number of turns make pulling it out in the off-season impractical/damn near impossible. It just received the breakout end upgrade due to water damage at the FOH end that affected several channels. Now the Mass connector lives in a custom PVC capsule with dessicant packets between performances.

My theory is that this particular channel simply absorbed water farther into the jacket. However I cut back as much as I could given its fixed path in the ground.

Can anyone think of another cause that I might be overlooking? Or am I just SOL?
@nussbaumjm87
Short answer: You're SOL.
Longer snswer: You've piqued my interest.
Very interesting / intriguing that the phantom powered mic works but NOT the plain Jane dynamic.
Do you have the ability to meter capacitance?
What if you measure all three conductors of pair one individually against a known good ground?
Then, for reference, make the same measurements with pair #2 to a known good ground.
Very interesting. Please let us know when you eventually get to the bottom of it.
Toodleoo!
Ron Hebbard.
 
I'm having problems with my copper snake. Channel 1 (send) only functions well with a condenser mic and phantom power. A dynamic mic comes in very degraded and at low volume. My cable tester shows good continuity on all 3 conductors, but of course that doesn't guarantee signal quality. It's a 250' 32 pair with a box at one end and a Whirlwind Mass to XLR/TRS breakout at the other. Channel setup is 24 sends, 7 returns, and a DMX line.

This snake sits in an underground outdoor conduit year round. The pipe diameter and number of turns make pulling it out in the off-season impractical/damn near impossible. It just received the breakout end upgrade due to water damage at the FOH end that affected several channels. Now the Mass connector lives in a custom PVC capsule with dessicant packets between performances.

My theory is that this particular channel simply absorbed water farther into the jacket. However I cut back as much as I could given its fixed path in the ground.

Can anyone think of another cause that I might be overlooking? Or am I just SOL?
@nussbaumjm87 Please tell us the specific makes and models of the two mics you're testing with.
It's an extreme long-shot but I want to be sure both mics output at mic level, that the mic that's working for you isn't an Electro Voice RE34, or whatever their model number was, that output a +4 line level directly from its 3 contact XLR connector.
Toodleoo!
Ron Hebbard.
 
If you can't get it figured out with the current wiring, maybe try switching the wiring to different pins on the connectors on that channel (i.e. switch wires between pins 2&3) and see if it makes a difference. I've found at times taking shots in the dark like can get lucky and lead to better understanding of what's going on.
 
I'm having problems with my copper snake. Channel 1 (send) only functions well with a condenser mic and phantom power. A dynamic mic comes in very degraded and at low volume. My cable tester shows good continuity on all 3 conductors

Time to put the cable tester aside and break out the multi-meter. (Cable signal loss is why Western Electric invented the Db concept!) Look at your loop resistance by jumping pins 1 and 2 at one end and measuring the resistance between 1 and two at the other end. Even with a 500 foot loop it should be darn close to 0 (consider any reading below 20 as good.) Next read from the 1/2 loop to pin one. It should be open circuit. Any reading below 10 meg would be an indicator of water intrusion. Generally, phantom powered microphones have a hotter output as the first stage of amplification is occurring inside the microphone. Mind you, they are still considered "microphone level", but are generally hotter than a passive microphone. That being said, usually ground leakage of the phantom voltage to the shield creates background noise, so a clean signal would hint against water. The last stage would be to inject a signal at -20 Db into the one end of the cable and measure the Db level at the other end (Old Ma Bell trick.) I would expect very little loss, but something is going on!
 
Time to put the cable tester aside and break out the multi-meter. (Cable signal loss is why Western Electric invented the Db concept!) Look at your loop resistance by jumping pins 1 and 2 at one end and measuring the resistance between 1 and two at the other end. Even with a 500 foot loop it should be darn close to 0 (consider any reading below 20 as good.) Next read from the 1/2 loop to pin one. It should be open circuit. Any reading below 10 meg would be an indicator of water intrusion. Generally, phantom powered microphones have a hotter output as the first stage of amplification is occurring inside the microphone. Mind you, they are still considered "microphone level", but are generally hotter than a passive microphone. That being said, usually ground leakage of the phantom voltage to the shield creates background noise, so a clean signal would hint against water. The last stage would be to inject a signal at -20 Db into the one end of the cable and measure the Db level at the other end (Old Ma Bell trick.) I would expect very little loss, but something is going on!

Great advice! I would add that measuring the values of a good pair (or a couple) using the method above and then comparing to the bad pair will show the deficiency without much question of what is a good/bad value.
 
The problem could be as simple as oxidation on contacts. The DC current drawn by the condenser mic might be enough wetting current to break the film resistance, which could explain why one mic works and not the other. The telephone company used to call it "sealing current" when they put DC current on line pairs to keep them working.

Caig DeoxIT D5 is an excellent contact cleaner that belongs in every audio tool box. I would especially flush the crap out of the mass connector because the mating surfaces are so small. After cleaning, follow up with DeoxIT Gold protectant.
 
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