Quick Find

Look Out For Free Delivery

Free Delivery now available on selected items.

Free Delivery Items

Support 24/7

Contact Support...

Contact our support team for any issues regarding your order & Technical issues.

AA Newsletter

Instant Savings! You'll receive unique discounts when you sign up for our club.

There is never any obligation to buy and you may cancel at any time. Joining is 100% free!

You will also receive News, Reviews, Competitions & Much More!



Diamond Audio D300.4 4 Channel Amp

4 x 75w RMS @ 2 ohm 4 Channel Amp

Diamond Audio D300.4 4 Channel Amp Free Shipping on This Item

Item No: D300.4

Delivery: 1-3 working days Warranty: 1 Year Availability: In Stock
14 Day Money Back Guarantee
Technical Help for Life

£329.99 £255.29


The new Diamond Audio flying “D” series takes the former D1, D3 and D6 amplifiers to the next level.  These amplifiers feature large cast aluminum endplates and our unique “Versa “ logo badge. This makes the installers job easier in custom installations.  The D600.1 and D1000.1 are strapable, allowing combining two amplifiers for one really high power channel.


While it is true you can’t be everything to everybody our new Diamond Audio flying “D” series amplifiers come close. We took the most popular features and models from the previous generation D1, D3 and D6 series amplifiers and combined them into one streamlined product range. The result is an easy to follow mix of performance and features that fit any budget. Common features include fully adjustable crossovers, up to 12dB of bass boost and RCA pass through outputs for easily adding additional amplifiers. Our new “Versa” badge makes for more flexible installation options. Some models include Hi-Level inputs for easy integration with factory audio systems. The new flying “D” series is only available at your local authorized Diamond Audio retailer.


  • Class AB amplifier topology
  • Bridgeable output capability (4 Ohms)
  • Stable into 2 Ohm stereo loads
  • 12dB/Octave high pass or low pass filter (50-250Hz)
  • Pass-Thru line output for daisy chaining amplifiers
  • Versatile for either full range or subwoofers
  • Pulse Width Modulated MOSFET switching power supply
  • Extruded aluminum heatsink
  • Nickel plated RCA low level audio inputs
  • Nickel plated power and speaker connector blocks
  • Power on and protection LED lighting for easy diagnostics
  • Thermal, short circuit, and low impedance protection
  • 0 - 12dB bass boost
  • Chassis mounted ATC/ATO type automotive fuses
  • Proudly designed and engineered in the USA


  • RMS @ 4 Ohm - 50 x 4
  • RMS @ 2 Ohm - 75 x 4
  • RMS @ 4 Ohm Bridged - 150 x 2

No Risk Concept

UK Leading Brand Car Audio Products Saving You Up to 47% off High Street Prices Backed by a RISK FREE 14 Day Money Back Guarantee & Delivered to your Door in 1-3 Days.

Need Help Deciding?

Try our interactive online buyers guide.

Answer a few questions about your specific needs, we’ll help you narrow your choices and focus in on the right products to make a smart buying decision.

View Buyer Guide...

100% Secure!

Shopping at Audio Assault is safe.

Audio Assault use Protx to securely process online payments. Our secure checkout is encrypted using 128-bit GeoTrust SSL certificates.

View Security Policy...

Express UK Delivery

Delivered to your door in 1-3 days.

All orders are dispatched using an Express 1 to 3 Business Day delivery service to UK mainland addresses if ordered before 2pm Mon to Fri.


14 Day Money Back Guarantee

Try your products for 14 days without risk.

If after trying them fully you find the product does not deliver everything that you want or expect, simply return your purchase for a replacement or full refund.