The Ashdown UK-RBM-500 (Rootmaster Bass Magnifier) brings the heart of the Rootmaster design ethos into a UK-built, Ice Blue package that balances power, portability, and tonal flexibility. Inspired by the RM-500-EVO III but refined for a new generation of bassists, this lightweight 500 watt head is engineered to deliver articulate, confident tone with unnecessary weight making it an ideal companion for busy musicians moving between rehearsals, gigs, sessions, and home practice.
At the core of the UK-RBM-500 lies a suite of tools designed to help bassists shape their sound with precision and creativity. The Sub-Harmonic Generator circuit adds a rich, octave-below layer that enhances both modern and traditional styles, while the onboard Compressor offers smooth control over dynamics for a balanced, professional result. Ashdown's Valve-Emulated Overdrive circuit provides expressive character, letting players introduce warmth, growl, or full-bodied grit depending on their musical needs.
The FX Loop slots easily into and pedal-based setup, ensuring that external effects integrate seamlessly with the amp's natural voice. When it comes to direct applications, the UK-RBM-500 is equipped with both a conventional DI output and Ashdown's Analogue Cab Sim DI, which recreates the feel of a mic'd Ashdown cabinet. This makes it ideal for live environments with in-ear monitoring, DAW-based recording setups, or any situation where consistent tone is essential.
A dedicated Headphone Out turns the UK-RBM-500 into a silent practice hub without compromising on sound quality. Combined with its rugged UK construction, compact footprint, and dependable Ashdown engineering, the UK-RBM-500 offers a complete and highly flexible solution for bassists seeking a reliable, great-sounding, and road-ready amplifier that magnified their tone and unmistakable Ashdown character.
SpecificationsIntrument Level: Impedance - 3.9M Ohms. Input Range 150mW to 20v p-p, Impedance - 10k Ohms. Input range 300mW to 40v p-p
Effects Return: Impedance - 22k Ohms. Input level 0dBu nominal
Line Input: Impedance - 22k Ohms. Input range 300mV
Effects Send: Impedance - 22k Ohms. Level 0dBu nominal
D.I Output: 420 Ohms balanced. Pre ground lift level -20dBu nominal
Speaker Outputs: Minimum Impedance - 4 Ohms
Frequency Response: -3dB at 22Hz and 22kHz
Headphone Output: 3.5mm Jack output @ 32 Ohms
EQ: Bass, Lo Mid, Middle, Hi Mid, Treble
Signal to Noise: Better than 80dB (E.Q. Flat)
Distortion: Less than 0.5% Thd
Output Power: 508 watts into 4 Ohms (dependant on local Mains Supply)
Dimensions: 89 x 311 x 235 mm
Weight: 3 kg
