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.
How to Tune a Car Amplifier: Set Your Gain the Right Way (2026)
Learn how to tune a car amplifier step by step — setting gain, crossover, bass boost and subsonic filter by ear or with a multimeter — to get clean, loud sound without clipping.
How to Install a Subwoofer in Your Car: Step-by-Step Guide (2026)
Learn how to install a subwoofer in your car step by step — wiring, amplifier setup, enclosure choice and gain tuning — plus exactly what gear you need, in stock at JS Ultimate Sounds.