Sound Storm Laboratories S4EQ 4-Band Car Audio Equalizer

The Sound Storm Laboratories S4EQ is a four-band car audio pre-amplifier that gives precise tone shaping, subwoofer control, and high-quality gold-plated outputs for cleaner signal transfer.

Designed for installers and enthusiasts who want fine control over their in-car sound, the S4EQ combines four adjustable frequency bands with flexible routing and high-level pre-amp outputs. Its compact footprint and dual-color illumination make it easy to mount and read in dim cabins, while the 7 V pre-amp outputs and gold-plated connectors help minimize noise and preserve audio fidelity.

How does the S4EQ let me tailor bass and subwoofer performance?

The S4EQ includes a dedicated variable subwoofer filter and a subwoofer level control so you can dial in low-end balance without affecting mid and high frequencies. A switchable phase selector helps align the sub with your main speakers for tighter bass response.

• Variable subwoofer filter for adjustable low-pass crossover
• Independent subwoofer level control for gain matching
• Phase selector to reduce cancellations and improve punch

What equalization options does the unit provide for tone shaping?

This pre-amp offers four EQ bands centered at 40 Hz, 150 Hz, 1 kHz, and 20 kHz with +/-18 dB of boost or cut at each center frequency. Those bands cover sub-bass, lower-mid, presence, and extreme treble so you can address common room and vehicle acoustic issues.

• 40 Hz band for managing deep bass
• 150 Hz band to tame muddiness in low-mids
• 1 kHz for vocal and instrument clarity
• 20 kHz for crisp high-frequency detail

Can the S4EQ integrate with multiple sources and installations?

The unit features two source inputs, an input selector, fader control, and master volume so it adapts to multi-source systems and different installation layouts. Gold-plated front, rear, and subwoofer outputs with a 7 V pre-amp level provide strong, low-noise signals to amplifiers or processors.

• Two source inputs for swapping head units or devices
• Input selector and fader control for system routing convenience
• Gold-plated outputs and 7 V pre-amp output for clean signal delivery

How does the size and usability fit typical car installations?

Measuring approximately 4-1/4" L x 6-13/16" W x 1-1/8" H, the S4EQ occupies a small footprint that fits behind dash panels or in consoles. Dual color illumination improves visibility for night driving, and physical knobs and switches make real-time adjustments simple without menu diving.

• Compact chassis for flexible mounting locations
• Dual color illumination for easy nighttime reading
• Hands-on knobs and switches for quick tuning on the fly

Who is this for? Installers, car audio hobbyists, and anyone upgrading a factory system who needs precise equalization and robust pre-amp outputs will find the S4EQ useful. It’s especially suitable when you want a dedicated subwoofer control and professional-grade connectors without adding a large processor. Sound Storm Laboratories backs the unit with a one-year online dealer warranty when purchased through authorized Amazon channels, making it a practical choice for system upgrades and tuned installs.