If there are only 2 thicker wires, then these are amplified lines for the sub.
You can use your own amp. But it has to accept input that is already amplified.
Or use hi-low amplifier.
Don't connect more powerful SUB directly to that line. it will not handle that.
Short range EVs <30kWh -- Medium range: 30-60kWh -- Long range: >60kWh
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