Mobile Electronics› Vehicle Audio and Components

Rockford Fosgate

USB charger

$219.99

SKU: R300X4

Out of Stock
Free Shipping over $200
$100 Minimum Order
30 Days Return

Overview

The Rockford Fosgate R300X4 is a versatile 4-channel amplifier designed to power your entire audio system. It can drive full-range or component speakers on the front channels while simultaneously powering subwoofers on the rear channels in bridged/mono mode.

This Class A/B amplifier features a MOSFET power supply and a cast aluminum heatsink for efficient operation and durability. It offers separate front and rear gain controls, a 12dB/octave Butterworth crossover, and a selectable 2 or 4 channel input switch.
Show original supplier description
The Rockford Fosgate R300X4 Prime 300 Watt 4-Channel Amplifier offers incredible versatility and Rockford Fosgate's renowned sound quality at an exceptional value. Engineered with a Class A/B topology, it combines the benefits of a Class-A preamp with a Class-B output stage for optimal performance. It features a robust MOSFET power supply and a cast aluminum heatsink for efficient heat dissipation and reliable operation. The R300X4 also includes a 12dB/octave Butterworth crossover with selectable high-pass/low-pass filters for precise tuning, along with onboard Punch EQ controls offering 0dB/+6dB/+12dB boost at 45Hz for the front and rear channels. Installation is made straightforward with high-level (4-pin MOLEX) and low-level (RCA) inputs, and screw terminals for 4 AWG power/ground and 8 AWG speaker wire connections. Visual indicators include a power/protect LED to monitor status. This amplifier is CTA-2006 compliant, ensuring its power ratings are genuine output figures. Key specifications include 50 Watts RMS x 4 at 4-Ohm, 75 Watts RMS x 4 at 2-Ohm, and 150 Watts RMS x 2 bridged at 4-Ohm. It operates within a 9-16 VDC range and has a frequency response of 20Hz to 20kHz +/-1dB. The amplifier dimensions are 1.98" x 6.77" x 13.19" (5 cm x 17.2 cm x 33.5 cm).

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

Fitment Guaranteed

Don’t gamble
on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandRockford Fosgate
Part NumberR300X4
CategoryMobile Electronics
5,000+ Trusted brands
1M+ Enthusiasts
5M+ Parts sold
(760) 282-4645 hello@motormia.co

Buy with Confidence

Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

View Full Return Policy

Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

View Full Shipping Policy