AshdownArtist Rex Brown UK-RB-800 800W Bass Amp Head - Black

Product overview
About this model
Developed in collaboration with Rex Brown of Pantera, the Ashdown UK-RB-800 Rex Brown Signature bass amp head combines 800W of output with extensive tone shaping and direct-output flexibility in a compact, 5.5 lb. design. Built on Ashdown’s Rootmaster platform, the UK-RB-800 features a 5-band EQ, Sub Harmonic Generator, compression control and variable valve-emulated drive for shaping clean and driven bass tones. Two Neutrik speakON/jack speaker outputs support connection to compatible cabinets, while balanced and analogue Cab Sim DI outputs provide flexible routing for live and recording applications. 5-Band EQ With Sub-Harmonic Processing and Drive The UK-RB-800 provides detailed tone shaping through a 5-band EQ covering bass, low-mid, middle, high-mid and treble ranges. Ashdown’s Sub Harmonic Generator adds synthesized low-frequency content beneath the original signal, while the compression control provides straightforward management of playing dynamics. Variable valve-emulated drive adds adjustable overdrive directly from the amp for expanding the range from cleaner bass sounds to more aggressive driven tones. Configurable Analogue Cab Sim DI for Direct Rigs An analogue Cab Sim DI expands the UK-RB-800’s options for direct connection to front-of-house systems and recording equipment. Selectable enclosure types, speaker configurations and horn options provide control over the simulated cabinet response, while a separate balanced XLR DI sends a post-EQ, post-effects signal. Together, the two DI options provide flexible routing for stage, recording and direct bass setups. Developed With Pantera Bassist Rex Brown As bassist for Pantera, Rex Brown helped provide the low-end foundation for the band’s influential heavy sound, including landmark tracks such as “Walk” and “Cowboys From Hell.” Developed in collaboration with Brown, the UK-RB-800 combines the output and portability of Ashdown’s Rootmaster platform with the EQ, drive, compression, sub-harmonic processing and direct-routing tools suited to a wide range of modern bass rigs. 5 lb. format designed for stage and studio use. From its iconic Bass Magnifier amps and bass cabinets to pedals, guitar amplification and artist-driven designs, the family-run company has remained dedicated to giving players distinctive tone and dependable performance while renewing its commitment to UK-built craftsmanship.

Reference
Full specifications
The complete catalog record, organized around the decisions musicians make when comparing gear.
3 detailsSound
- Effects send impedance
- 22 kohms
- Effects return impedance
- 22 kohms
- Minimum impedance
- 4 ohms
2 detailsBody & build
- Color
- Black
- Country of Origin
- UK
10 detailsConnections & power
- DI output level
- 0dBu nominal
- High instrument input impedance
- 3.9 Mohms
- Effects return input level
- 0dBu nominal
- Low instrument input impedance
- 22 kohms
- High instrument input range
- 150mV–20V p-p
- Low instrument input level
- 0dBu nominal
- Balanced DI output
- 1 x XLR, post-EQ and post-effects
- Power output
- 800W
- DI output impedance
- 420 ohms
- Speaker outputs
- 2 x Neutrik speakON/jack
28 detailsOther
- Compression
- Smooth compression control
- Distortion
- Less than 0.5% THD
- Effects send level
- 0dBu nominal
- Tier
- new
- Drive
- Variable valve-emulated drive
- Frequency response
- -3dB at 22Hz–25kHz
- Sub-Harmonic Generator
- Yes
- Power requirements
- 115–230V
- Bass
- ±15dB at 100Hz
- Category Source
- detail
- High mid
- ±15dB at 1.6kHz
- Product type
- Bass amplifier head
- Color
- Black
- Signal-to-noise ratio
- Better than 80dB with EQ flat
- Artist signature
- Rex Brown
- Korena Special
- false
- EQ
- 5-band
- Middle
- ±15dB at 660Hz
- Dimensions (WxHxD)
- 12.24" (31.1 cm) x 3.5" (8.9 cm) x 9.25" (23.5 cm)
- Weight
- 5.51 lbs (2.5 kg)
- Country of origin
- UK
- Product Type
- Bass amplifier head
- Cab Sim DI
- Analogue cab simulation
- Model
- UK-RB-800
- Treble
- ±15dB at 7kHz shelving
- Guitar Center Exclusive
- Yes
- Source Id
- site51500000471727
- Low mid
- ±15dB at 340Hz






























