Best In-Wall Rated Cable for Subwoofer Run?

There is no getting around it, I need an In wall run to my sub. I’m confused whether this would be speaker cable (analog) or coax (digital); but I’m thinking it’s an analog signal coming from the processor to the amp built into the subwoofer.
Specifics would be helpful.
What amp/processor and what sub are you trying to connect.
Length of run?
Thanks! Sorry.

Ok Marantz pre/processor 7704 and Marantz amp 8077.

About a 25ft run.

The sub is a Monitor Audio RXW-12.
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HI Craig,

Analysis Plus makes a good in-wall rated subwoofer cable that is very reasonably priced for RCA/RCA cable.  Good Luck