Rose Electric Audio B-15 Valve Bass Preamp

B-15 Valve Bass Preamp

£699.00

Highlights

• Tube preamp and direct box recreating the Ampeg B-15 Flip Top preamp
• Warm, weighty lows, focused mids and natural valve compression for bass and guitar
• Responsive dynamics and familiar feel that reward touch, volume changes and playing nuance
• Musical EQ and gain structure offering wide tonal range with simple, intuitive control
• High-voltage all-analogue circuit with 6SL7 valve running at full 300 volts
• Designed and built by hand in the United States by electronics engineer Nick Rose
• Rugged all-metal enclosure built for touring, studio use and everyday pedalboard reliability
• Clear, understated graphics with excellent readability on dark stages and crowded pedalboards
• Bright LED power indicator provides instant status visibility during setup and performance
• True bypass switching preserves signal integrity and original instrument tone when disengaged
• Fully analogue signal path delivering consistent tone without digital conversion
• Side-mounted input, output and power jacks suit tidy, space-efficient pedalboard layouts
• Covered by manufacturer warranty for long-term confidence in performance and build quality

Description

The Rose Electric Audio B-15 is a tube preamp and direct box designed to place the sound and feel of a classic Ampeg B-15 Flip Top bass amplifier at the centre of a modern pedalboard or recording setup. It functions as the front end of a rig rather than an effect in the traditional sense, offering bass players and guitarists a complete valve preamp that can feed a power amp, a recording interface, a mixing desk or a conventional amplifier. It is intended for players who want the response and authority of a studio-proven bass amp preamp in a compact, practical format, whether for live performance, recording or silent stage use.

Sonically, the Rose Electric Audio B-15 delivers the rounded low end, articulate midrange and gentle high-frequency roll-off that made the original B-15 a benchmark for bass recording. Notes have weight and depth without sounding blurred, with a natural compression that enhances dynamics rather than flattening them. The low end remains firm and controlled, even with extended-range basses, while the midrange carries detail and warmth that helps lines sit comfortably in a mix. With guitar, the character shifts towards a thick, harmonically rich clean tone that responds well to picking nuance and volume changes. The sound interacts naturally with amplifiers and recording equipment, retaining clarity while adding the unmistakable texture of a high-voltage valve circuit.

In use, the Rose Electric Audio B-15 feels immediate and responsive. Touch dynamics translate clearly, encouraging expressive playing and making small changes in attack or instrument volume easy to hear and feel. The layout and behaviour are intuitive, allowing players to focus on their performance rather than on adjusting settings. It suits both precise, controlled playing and more relaxed, groove-focused styles, offering a sense of familiarity that invites longer sessions and creative exploration.

Sound shaping is based on the preamp section of the original amplifier, providing a musical EQ that is voiced for practical, real-world use. Adjustments have a broad, usable range, making it easy to move from deep, supportive bass tones to more forward, defined sounds without drastic changes. The controls respond smoothly and predictably, allowing quick adjustments on stage or in the studio without the need for constant fine-tuning.

At the heart of the design is a full internal 300-volt power supply running a 6SL7 valve, ensuring the valve operates exactly as intended rather than being starved for voltage. This approach is central to the pedal’s tone, headroom and dynamic behaviour, delivering the performance associated with a proper valve preamp. A transformer-isolated balanced XLR output provides a clean, noise-resistant signal for direct connection to mixing desks or interfaces, alongside a standard quarter-inch unbalanced output for use with amplifiers and other pedals. Power is supplied via a 9 to 18 volt DC input at up to 1 amp, centre-negative, compatible with robust supplies such as a 1 Spot or equivalent (not supplied).

Every Rose Electric Audio B-15 is designed and built by hand in the United States by qualified electronics engineer Nick Rose. Each unit is assembled one at a time, reflecting the boutique nature of Rose Electric Audio pedals and the attention to detail that comes with small-scale, engineer-led production. The all-metal enclosure is solid and reassuring, suited to regular transport and the demands of live use while remaining compact enough for practical pedalboard integration.

The graphics are clear and understated, with legible markings that remain visible under stage lighting and in studio environments. A clear LED indicator provides immediate confirmation of power status, reducing guesswork when setting up or troubleshooting. The bypass circuitry is designed to maintain signal integrity, ensuring the instrument’s tone remains intact when the pedal is disengaged. Input, output and power connections are arranged with pedalboard use in mind, making cable routing straightforward and keeping setups tidy.

The Rose Electric Audio B-15 is supplied with the confidence of a proper manufacturer’s warranty, reflecting the care taken in its design and construction and offering reassurance for long-term ownership.

As a whole, the Rose Electric Audio B-15 stands out by offering the authentic preamp sound of a revered bass amplifier in a carefully engineered, boutique pedal format. It combines faithful tone, reliable performance and thoughtful practicality, making it a valuable and distinctive addition to any bass or guitar rig where classic valve character is a priority.

Controls

• MASTER: Sets overall output level, balancing stage volume and direct signal without altering core tone
• VOLUME 2: Fine-tunes second gain stage level, shaping output drive and headroom interaction
• GAIN 1: Controls initial valve drive, moving from clean warmth to rich, dynamic saturation
• BASS 1: Adjusts low-frequency depth, from tight and controlled to full, supportive bass weight
• TREBLE 1: Shapes high-frequency clarity, adding presence and definition without harshness
• GROUND LIFT/BALANCED OUT TOGGLE: Eliminates ground noise on XLR output for clean, reliable direct connections
• POWER TOGGLE: Provides clear on off control with immediate visual confirmation
• BALANCED OUT: Transformer-isolated XLR output for noise-free recording and front of house feeds
• INPUT: High-impedance input preserves instrument character and touch sensitivity
• OUTPUT: Unbalanced quarter-inch output feeds amplifiers or pedals with consistent level and tone

Components and Technical Specifications

• High-voltage all-analogue valve preamp circuit based on original Ampeg B-15 design
• One 6SL7 valve operated at full 300V for authentic headroom and dynamic response
• Internal 300V power supply ensures correct valve operation and consistent tone
• Transformer-isolated balanced XLR output reduces noise and ground loop issues
• Parallel unbalanced quarter-inch output for amplifiers, pedals and monitoring chains
• High-impedance input maintains pickup clarity and playing dynamics
• Low-noise signal path optimised for studio recording and live performance
• Premium resistors and capacitors selected for stability, tone accuracy and long-term reliability
• Compatible with professional pedalboard power supplies, including 1 Spot units
• No battery operation to ensure consistent voltage and optimal valve performance
• Powered by standard 9V to 18V centre negative supply (not included)
• Battery operation not supported
• Current draw: 1A

Current draw may vary slightly depending on control settings, circuit behaviour, and active features such as gain stages, modulation, filtering, or reverb tails. For best performance, use a high quality isolated power supply that matches the pedal’s current requirements. Always refer to the manufacturer’s recommendations, as incorrect powering may cause damage.

Enclosure Dimensions

• Depth: 119 mm / 4.7 in
• Width: 243 mm / 7.3 in
• Height: 56 mm / 2.2 in

Weight

• 814 g
• 1.79 lbs

Official UK Dealers

FX Pedal Planet Limited and FX Pedal Planet Online Store proudly serve as official UK dealers for Rose Electric Audio effects pedals. If we do not have the specific Rose Electric Audio pedal you are looking for, please reach out to us via the contacts page, and will order it on our next stock order for you at the best price and customer service.

Buy Today and Pay Over Time

To give our customers flexibility and a pleasurable shopping experience, FX Pedal Planet Online Store accepts Klarna, Afterpay, Clearpay and Google Pay.

Klarna is a smooth and safe way to get what you want today, and pay over time. Afterpay allows customers to pay in four interest free instalments, budget your spending and earn rewards when you shop.

UK Deliveries

For our UK customers, we provide FREE 24 hour DHL tracked and signed delivery, ensuring your order arrives swiftly and securely.

International Deliveries

International deliveries are dispatched with DHL, ensuring fast shipping and efficient processing through customs.

For more information on deliveries and charges, please refer to our Deliveries and Charges.

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