Which copper AWG keeps this exact speaker run inside the chosen loss target?
Measure the one-way route, add slack, double it for the electrical loop, and use the purchased cable's ohms per kilometre. Then compare loss at the lowest relevant speaker impedance, not only the nominal label.
Method
Cable and speaker form a resistive divider. The page reports delivered-power ratio, dB change and a resistive effective-damping estimate, while keeping installation rating and terminal fit as separate evidence.
Important limitation
Speaker impedance varies with frequency and exact cable resistance varies by construction and temperature. This cannot approve in-wall wiring, connector fit or audible performance.