【ARC Audio KS 300.4 V3｜A Compact 4ch Power Amplifier for High-Quality Sound】

You’d like to refine your car audio sound even further, but it’s difficult to add a large amplifier inside the vehicle. If that sounds like you, consider ARC Audio’s KS 300.4 V3, a 4ch power amplifier.

As its KS series philosophy—"Solid" (reliable), "Proven" (proven), and "Quality" (quality)—suggests, this model is designed with an emphasis on balancing ease of handling and sound quality. With a G/H-class amplifier design, it delivers ample power and adjustment features in a compact chassis.

It’s designed to be flexible for building your system. Of course, you can drive the front and rear speakers with 4 channels, but it also makes it easy to configure your setup depending on your goals—such as driving the front speakers more powerfully or combining a subwoofer via bridged connection. It’s also well-suited for people who feel that a factory navigation system or existing car audio system sounds lacking, those who feel the sound gets strained when you turn up the volume, and those who want to hear vocals and instrument sounds more clearly.

Adding an amplifier doesn’t simply make the sound louder. By delivering a stable signal to the speakers, the sound’s attack and overall headroom can change—sometimes making it easier to pick out fine details in the music you listen to every day. However, the final result isn’t determined by the amplifier alone; it varies depending on the speakers, DSP, subwoofer, power supply, wiring, installation method, and in-vehicle tuning.

At LOGON, we confirm your vehicle model, what comes with your factory system, the music you typically listen to, your volume preferences, and your budget—then work with you to decide how best to integrate the KS 300.4 V3. Even with the same amplifier, the impression can differ depending on where and how it’s installed, how it’s connected with other equipment, and how it’s adjusted at the end. In our view, that’s the meaning of consulting a specialty shop: instead of unnecessarily adding more equipment, you can move forward by organizing which parts of your current system deserve investment.

If you’re considering an amplifier replacement or a system upgrade, please tell us your vehicle model, your current setup, and what you’re unhappy with in your sound. While checking your actual vehicle, we’ll also propose whether the KS 300.4 V3 is a good match—using an approach that minimizes changes later on.

Key Specifications / Specs

【Basic Information】
Product name: KS 300.4 V3
Brand: ARC Audio
Type: 4ch power amplifier
Amplifier class: G/H class

【Output】
4Ω: 120W × 4
2Ω: 190W × 4
Bridge 4Ω: 380W × 2

【Acoustic Performance】
S/N ratio: 115dB at full output
S/N ratio: 95dB at 1W
Frequency response: 5Hz–50kHz

【Crossover / Adjustment Functions】
Crossover: 55Hz–5.5kHz
Slope: −12dB/oct
Bass boost: +18dB @45Hz