Big 3
What Is the Big 3 Upgrade? (And How to Do It) — Car Audio Guide 2026
What is the Big 3 upgrade in car audio? Learn what it is, what gauge wire to use, whether it's worth it, and how to do the Big 3 upgrade step by step — plus the wire you need in stock.
How to Add a Second Battery for Car Audio (Wiring Guide 2026)
Learn how to add and wire a second battery for car audio — when you need one, AGM vs lithium, isolators, and a step-by-step wiring diagram — plus the batteries you need in stock.