The Ashdown UK-CTM-300 Classic Tube Magnifier bass amp head delivers 300W through an all-valve architecture built around six KT88 output tubes and a five-valve preamp section. Built in the UK and available as a Guitar Center Exclusive, the CTM-300 provides LOW and HIGH instrument inputs for passive and active basses, a 2-ohm minimum speaker load and a passive Bass, Middle and Treble EQ complemented by Mellow, Deep, Mid Shift and Bright voicing switches. A tube-driven, transformer-derived DI, effects loop, dual-function VU/bias meter and individually fused output tubes provide extensive routing, monitoring and maintenance features for stage and studio bass rigs.

Six KT88 Tubes With a Five-Valve Preamp

The UK-CTM-300 uses six KT88 output tubes to produce 300W, paired with a preamp section built around ECC83, ECC832, ECC99 and ECC82 valves. This all-valve signal path extends from the preamp through the power section, while support for a 2-ohm minimum speaker load provides flexibility when configuring compatible bass cabinets. LOW and HIGH instrument inputs accommodate different input levels from passive and active basses.

Passive EQ, Voicing Switches and Tube-Driven Routing

A passive tone section with Bass, Middle and Treble controls provides the foundation for shaping the CTM-300, while Mellow, Deep, Mid Shift and Bright switches offer additional voicing options for different instruments, cabinets and playing styles. The tube-driven, transformer-derived DI output includes Pre/Post switching for live and studio routing, while an effects send and return support integration of external pedals and processors.

UK Custom Shop Construction and Bias Monitoring

Hand-built in the Ashdown UK Custom Shop, the CTM-300 is housed in an 18 mm marine-grade birch-ply enclosure with heavy-duty flip-style handles and an internal fan. Its front-panel VU meter provides output-level indication during normal operation and also functions as a bias meter for monitoring the output tubes. Individually fused output tubes and user-accessible bias adjustment provide additional tools for tube maintenance. Built in the UK and available as a Guitar Center Exclusive, the UK-CTM-300 combines high-output all-valve amplification with extensive tone shaping and practical monitoring features.

Ashdown Amplification Arrives at Guitar Center

Since 1997, Ashdown has built its reputation on powerful, road-ready amplification trusted by bassists on stages around the world. From its iconic Bass Magnifier amps and bass cabinets to pedals, guitar amplification an