Description
Musical Fidelity B1xi Integrated Amplifier
The Musical Fidelity B1xi Integrated Amplifier channels Musical Fidelity’s renowned amplifier expertise into a versatile, high-performance package.
Driven by the design principles of their flagship models, the B1xi delivers 100W per channel into 4 ohms through a refined Class A/B circuit, offering a rich and dynamic tube like sound.
The team designed it for today’s diverse listening needs, it features a comprehensive input selection: MM phono stage, coaxial and optical digital inputs, ARC, Bluetooth, and three RCA line inputs—all engineered for seamless source integration.
A variable RCA pre-out supports subwoofer connection or bi-amping, while a 5V USB-C output provides convenient and clean high-quality power for an external streamer.
Encased in robust all-metal construction with solid metal controls and a solid aluminum front panel, the B1xi offers the sonic and build quality Musical Fidelity is known for, delivering a pure, uncompromised audio experience for discerning music lovers.
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Reviews
- “The best sounding amplifier I‘ve encountered to date below £1,000. Exceptional clarity, sense of timing, and drive. The B1XI produces a sound field that is wider, deeper, and more layered.” Watch The Video A British Audiophile – 09/2025
- “The Musical Fidelity feels like the more potent amplifier. The B1xi is able to exert a level of control over lower frequencies. This is a fundamentally enjoyable amplifier to listen to. There is fundamental rightness to the sound that is hard not be taken by.” Visit the Website Ed Selley – avforums 08/2025
- “There’s a potency to the sound. The B1xi gives it a texture and immediacy. This is a clever and capable new amp that demonstrates enough strength in depth to warrant being on any sub-£1,000 audition list.” Ed Selley – Hi-Fi Choice 10/2025
- “The B1 is a practical and very well-equipped amplifier that brings the characteristic virtues of the larger Musical Fidelity amplifiers in a compact, delightfully affordable form.” Simon Mendel – Stereo 08/2025
- “Every detail is just right, from the subtle to the bold. A rare combination of charm, performance and everyday practicality that elevates it far above its price range.” Andreas Günther – Audio Test 10/2025
- “It sounds – not unimportantly – great, has ample connection options, and operates perfectly as it should. This is exactly the no-frills amplifier you’d want back in the day as a first amplifier (intended to last).” Ward Maas – HVT 09/2025
- “You can even „melt“ over the sound of the B1xi. It has so much charm and emotion. Its strengths are its tone and plasticity.” editors – Audio Poland 08/2025
- “The sound of the B1xi lacked the artificial brightness or harshness that plagues other amps in its class, while at the same time illuminating the midrange very clearly. The B1xi sound could be described as photorealistic” Kari Nevalainen – HiFimaailma 10/2025
Features
Pure Class A/B Excellence with True High-End Audiophile Design
Transistor amps in Class A/B are best after tubes and Class A amps. Musical Fidelity is tube like sound and power. The B1xi delivers 60 watts per channel into 8 ohms, 100 watts into 4 ohms and 140W peaks into 2 ohms. It won’t struggle to drive a wide range of speakers, even power-hungry models.
Discrete power and toroidal transformer
The fully discrete Class A/B power amp, complemented by its dedicated power supply and generously proportioned toroidal transformer, guarantees reserves for proper peak delivery and a wide dynamic range. Power hungry and difficult speakers are driven with ease. Low impedance dips are managed gracefully and the judiciously rated output devices won‘t faulter under any load.
Low noise preamp and phono stage
The preamp section features its own dedicated linear power supply—a rarity in integrated designs. This separation ensures ultra-low noise and excellent channel separation, rivaling high-end pre/power separates.
Volume control is handled via a motor-driven analogue potentiometer, preserving signal purity—unlike many modern digital volume controls that compromise fidelity due to a loss in signal resolution.
Vinyl lovers will appreciate the B1xi’s exceptionally low-noise, high-gain phono stage. Carefully tuned for musicality and detail, it brings out the best in your MM cartridges without adding coloration or distortion.
Separate digital boards
Digital and analogue hardware needs to be carefully separated from each other. Even the smallest amount of RF interference is known to cause trouble for analogue amplifier stages. Therefore, the digital and ARC boards are physically separated on their own PCBs and have their own linear power supply.
Drawing from our decade long experience in designing DACs (recently with our ground-breaking Nu-Vista DAC and M8x DAC), the B1xi uses a carefully trimmed DAC design using the superb ESS9018 chip.
The digital coaxial and optical inputs accept high-resolution sample rates up to 24bit and 192kHz and the HDMI ARC input allows your home theatre to be brought to life and properly invigorated by the powerful B1xi analogue amp stages.
Uncompromisingly heavy mechanical design
The inclusion of high-end elements such as the robust metal controls, extruded aluminium front panel, and a chassis crafted entirely from metal, the B1xi occupies an enviable position for discerning audiophiles seeking an unadulterated high-end amplifier.
No WiFi on Purpose
The B1xi remains committed to sound quality instead of WiFi, a display and an App. There is NO WiFi streaming on purpose. They’ve seen a surge in offerings from HiFi companies with all-in-one solutions and unfortunately, such developments are HUGLY EXPENSIVE and on top very maintenance heavy.
Consequently, manufactures started to save the money somewhere: Cheap plastic cabinets, low-cost digital amplifiers, low-cost power supplies. Musical Fidelity stands for sound quality and robust design that lasts for decades. MF INVEST their money and resources in top-tier hardware and the pursuit of optimal music reproduction.
This means: Robust mechanics – Discrete circuits – Huge transformers – Class A/B amps. Fast moving streaming technology is best kept separate and therefore will not negatively impact the lifecycle of the B1xi. For that reason, the B1xi features a high-quality isolated USB C 5V power output for your favorite modern streamer – effectively also doubling as a power supply upgrade for it.
The Audiophile Truth
Any RF frequencies are influencing the performance of the analogue amplifier. Consequently, our design team, headed by their chief technical director Simon Quarry:
- took one year to improve the layout of the circuitry and match the boards in relation to the transformer
- carefully selected components for long-term availability and reliability, to avoid any change which would cause a redesign of the product
- RF shielding and board placement to avoid interference with analog stages
The B1xi achieves price/performance like never before for Musical Fidelity. With carefully selected components, precisely tuned circuitry layout and years and years of research and development the B1xi stays true to the Musical Fidelity philosophy and makes high-end affordable like never before.
FAQ’s
- What is the power output of the Musical Fidelity B1xi? The B1xi delivers 60 watts per channel into 8 ohms, providing ample power for a wide range of hi-fi speakers in small to medium-sized rooms.
- What inputs does the B1xi Integrated Amplifier have? It includes multiple line-level RCA inputs for connecting CD players, streamers, DACs, and other sources, plus a dedicated input for integrating with home audio setups.
- Does the Musical Fidelity B1xi have a built-in phono stage for turntables? No, the B1xi does not include a built-in phono preamp, so you’ll need an external phono stage to connect a turntable.
- Can I use the B1xi with both bookshelf and floorstanding speakers? Yes, its robust power supply and 60W per channel output make it suitable for most bookshelf and many floorstanding speakers, provided they are of reasonable sensitivity and impedance.
- What makes the B1xi different from other integrated amplifiers in its class? The B1xi blends Musical Fidelity’s classic British sound—smooth, detailed, and musical—with minimalist design, high-quality components, and a focus on pure, low-distortion amplification rather than extra features you may not need.
Specifications
Amplifier
- Power, both channels driven @ 1% THD: 60 Watts per channel into 8 Ohms; 100W into 4 ohms; 140W peaks into 2 ohms
- Power, both channels driven @ 0.09% THD, 20Hz to 20 kHz: 50 Watts per channel into 8 Ohms; 80W into 4 ohms
- Voltage 21 Volts RMS, 20Hz to 20 kHz; onset of clipping
- 30 Volts peak to peak
- Current 8 Amps peak to peak
- Damping factor 30
- Output devices 1 pair per channel
Line input
- THD+N < 0.02 % typical, 20Hz to 20 kHz
- Signal / noise ratio > 100dB ‘A’-weighted
- Input impedance 47k Ohms
- Frequency response +0, –3dB, 10Hz to 30 kHz
Phono input
- Sensitivity (nominal): 5mV (suitable for cartridges giving 1.5mV or more including high output MC types)
- Signal / noise ratio: >70dB ‘A’-weighted
- Input impedance: 47k Ohms
- Input capacitance: <100pF
- Gain: 42dB
- Frequency response: RIAA/IEC ±1dB, 20Hz to 20 kHz
Connections
- Line level inputs 3 pairs line level RCA connectors
- MM phono input
- Optical, coaxial, ARC digital inputs (up to 24bit/192kHz stereo PCM)
- Bluetooth 5.1 input
- 1 pair line level RCA connectors, preamp outputs for e.g. bi-amping
- Speaker outputs 1 pair 4mm banana plug/binding posts
Power requirement
- Mains voltages 115/230VAC 50/60Hz (factory pre-set)
- 100VAC 50/60Hz (alternative)
- Consumption 280 Watts maximum
Weight
- Unit only, unboxed 7.2 kg
- In shipping carton 8.9 kg
Dimensions
- Wide 430 mm
- High, including feet 90 mm
- Deep (front to back) including terminals 324 mm










































