Elk M1TWA audio amp wiring question

[mikefamig]

I am still planning my Elk M1 install and have a question regarding the speaker and microphone wiring.
 
I plan to mount the TWA inside the structured box with the controller and bought 18/4 speaker wire for a 250' run. I would like to use two of the speker leads for the speaker output and the other two leads for the microphone bat an worried about cross talk. Has anhyone tried this? Is a separate shielded cable necessary for the microphone?
 
TIA,Mike.

 

[RAL]

ELK recommends twisted pair for the microphones.  I would go a step further and use shielded twisted pair.   In another thread on a similar subject, pete_c said he had good results using twisted pair and audio baluns.

 

[mikefamig]

ELK recommends twisted pair for the microphones.  I would go a step further and use shielded twisted pair.   In another thread on a similar subject, pete_c said he had good results using twisted pair and audio baluns.

I planned to pull an extra cat6 cable so maybe I'll use a pair from that cable and add the balun if I have trouble.