I am tasked with running a loudspeaker to a remote building. The total run length is around 275 feet, with the outdoor portion being around 165 feet. The cable is Cat5e 24awg unshielded, silicone filled cable installed in a 2-inch PVC conduit buried 6-12 inches underground.
The loudspeaker amp documentation (Viking PA-2A, page 6) shows that the run length is suitable for the wire gauge, and also states that multiple pairs can be ganged to increase current capacity if necessary. I can use up to all 4 pairs if needed. They also state that step-up/step-down transformers can be used for very long runs (see this), which I will do if the volume is not acceptable.
I said all this to hopefully avoid unrelated replies such as "it won't work/cable size is wrong/etc".
My question is regarding lightning protection. Since the cable is outside/underground for 165 feet, do I need any type of lightning arrester to protect my amp and other electronics?
If so, I'm not sure what type of arrester to use. Most such protection devices are for coax cable, and I've only seen a few screw terminal devices, such as this one, which is only rated for 12VDC. It's my understanding that the amp outputs ~70V to the loudspeaker speaker horns, so I assume this type of arrester would not work.
I would appreciate your advice on how to proceed.
EDIT: I should have known L-Com would have something like this. Is this overkill? I'm only running one pair, not stereo.