Bulk lavalier mic cable

[Ervin Farkas]

Hello fellow techies,

I'd like to replace lavalier mic cables (let's not get into soldering and other issues on the mic end for now).

I am considering Mogami bulk wire W2697, W3031 or W2901 , see MOGAMI® - Miniature Balanced / Lavalier Microphone Cables - anyone care to translate for me the tech specs on that page? Those noise numbers look confusing - how in the world can one model have 200 times as much noise as the other when the only difference is the braiding (OK, wire size too). What's better, the big number or the small?

Any opinion on differences between served vs. braided vs double served models? Does anyone have a recommendation for another, better cable?

What's the longest I can make a lav cable before it will start picking up noise?

Thank you,

[Richard Crowley]

I see 4x difference between W2697 (spiral, 50mV) vs. W3031 (braided, 200mV).
The description says that shield construction is the only difference, otherwise identical.
Those numbers look reasonable to me.

Is their electrostatic noise test methodology published? Perhaps reading that would be enlightening.

The environmental factors are far more influential than the length of the cable. You can probably go 100 feet out in the desert, and maybe not 6 inches next to a GSM cell phone. The shielding properties of the cable are only a part of the total interference immunity picture (and not a particularly large part).

I thought the description was particularly helpful. Discussing the tradeoffs between shielding ability, flexibility, mechanical strength, terminability, etc.

[Ervin Farkas]

Thanks Richard,

Electrostatic noise is indeed 50mV for the W2697 and 200mV for W3031, but it is 1mv for W2901.

1 to 200 is 200 times higher - that's what I am referring to.

[Richard Crowley]

Yes the difference between W3031 (200mV) and W2901 (1mV) seems strange to me. That is why I suggested that maybe their testing methodology could explain the unusual difference. I do NOT believe that the W3031 is 200x (or even 4x) "more noisy". I think those are laboratory experiments that don't necessarily reflect Real-World performance. Perhaps their test methodology could be improved to be more representative of actual use.

I have retrofitted mics with long pieces of this kind of cable and I didn't see any particular difference vs. using "conventional" mic cable. Yes, the higher capacitance could cause some greater high-frequency rolloff, but I don't think that will be significant for speech program material.

OTOH, I WOULD expect that longer sections of unbalanced, medium impedance runs will, by definition, be more susceptible to things like cellphone RFI, etc. I am assuming you are talking about the wiring from a small lav mic head to the power supply or connector which is unbalanced in most brands and models.

[Giroud Francois]

whatever is the methodolgy they use, one cable is can accept 200mv when the other can only stand for 1mV. Then you can choose what you need, knowing the 1mV cable is so because they tried to improve mechanical strength versus electrical performance.