Description
In 1990, Musical Fidelity introduced the groundbreaking A1000, the very first Super Integrated amplifier. It was met with enthusiastic acclaim and still commands high prices in the second-hand market today. The A1000 marked the beginning of a lineage of Super Integrated Amplifiers from Musical Fidelity, including the NuVista M3, Tri Vista 300, kW500, M6/500i, NuVista 800, and NuVista 600, all of which were warmly embraced by audiophiles. The M8xi is the latest and most exceptional addition to this lineage.
General Description The M8xi is a unique preamplifier with two monobloc power amplifiers sharing a common chassis. Each amplifier has its dedicated heat sink and separate transformer, offering true dual mono operation. The preamp boasts its independent power supply and is positioned in close proximity to the input ports, resulting in extremely short PCB tracks. This design ensures that both channels maintain ultra-low impedance as soon as the signals enter the amplifier. Each channel is equipped with twelve substantial bipolar transistors, providing a peak-to-peak current of 200 amps. The construction of the M8xi radiates a sense of robustness and quality, with high-quality metalwork and a custom-made fine-line aluminum front panel.
New Circuitry Over the past five years, our power amplifier circuitry has undergone significant development. In our pursuit of enhanced performance and value for our customers, we focused on maintaining our low-feedback configuration. The challenge was to improve efficiency and performance without compromising sound quality. Our innovative solution, which we believe to be brilliant, is integrated into the new M8xi power amplifier design. It delivers increased power, reduced distortion, and improved sound quality. Remarkably, the output stage efficiency has been enhanced, providing about 10% more power for a similar power supply voltage. Most notably, the entire driver stage operates in pure Class A, significantly affecting sound quality. The soundstage becomes wider, and micro and macro dynamics gain impact, particularly evident with well-recorded piano music. The percussive nature of pianos, often indiscernible on most Hi-Fi systems, becomes strikingly clear when using the M8xi. Vocals exhibit more subtlety, detail, and presence, while large-scale music gains depth, width, and remarkable dynamic presentation. In essence, the M8xi offers all-around excellence, delivering the sound characteristics of a small Class A amplifier with substantial power.
The DAC The M8xi also incorporates a 5-input DAC, responding to the growing prevalence of DACs in integrated amplifier designs. This addition simplifies the connection of various digital sources and maintains high performance independently of the amplifier. To enhance integrity, the DAC has its dedicated power supply. Employing the Texas Instruments PCM5242 TI DAC chip, known for its low distortion and noise, the M8xi offers 2 x coaxial (S/PDIF), 2 x optical (S/PDIF), and 1 x asynchronous USB Type-B inputs. Both the coaxial and USB inputs support hi-res audio streams up to 24-bit / 192kHz, while the optical input supports up to 24-bit / 96kHz. To maximize performance, all data streams are up-sampled and re-clocked by an internal converter to reduce jitter and eliminate unwanted artifacts in the sound.
Technical Performance The M8xi delivers a robust 550 + 550 watts per channel into 8 ohms. It exhibits exceptional stability and linearity, with distortion levels lower than 0.005% within the audible frequency range of 20 Hz to 20 kHz. The M8xi’s linearity and consistency are remarkable, and it remains unconditionally stable, effortlessly driving any loudspeaker with ample power reserves.
Our Approach to Technical Measurements We firmly believe that an amplifier should be completely neutral—a “straight wire with gain.” Achieving this is complex but paramount. Our goal is to create low-feedback circuit and PCB designs that deliver complete neutrality, transparency, and exceptional technical performance. We use technical performance as a means to validate the overall amplifier system concept. We maintain that technical performance cannot be solely defined by distortion at 1 kHz. We insist that an amplifier must exhibit very low distortion across the entire 20 Hz to 20 kHz frequency range and beyond. The M8xi’s distortion levels remain remarkably consistent from 10 kHz to 50 kHz, a testament to our circuit design and PCB layout.
Noise Ratio Quiet amplifiers are essential for preserving low-level details and achieving a wide dynamic range. Dynamic range spans from the quietest to the loudest, and an amplifier must excel in both aspects. The M8xi excels in maintaining a low noise floor, contributing to its impressive dynamic range.
Sound Quality The M8xi offers an effortless, fluid, and dynamic listening experience. It doesn’t sound “loud” but rather “right.” Dynamics are handled with grace and poise, without any distortion, delivering pure, unadulterated music. It possesses the characteristics of a superb small Class A amplifier with abundant headroom, resulting in sonic perfection.
Stereophile Review A Stereophile review declared, “I can say with confidence that the extremely neutral Musical Fidelity M8xi is not only the most powerful and least expensive of the bunch but also one of the best-sounding.”
Amplifier
- Power Output (20Hz – 20kHz): 550 Watts per channel into 8 Ohms (870W into 4 Ohms); Peak 1.6kW into 2 Ohms
- Maximum output voltage: 67 Volts RMS, 20Hz to 20 kHz; onset of clipping (190 Volts peak-to-peak)
- THD+N: <0.004% typical, 20Hz to 20 kHz (XLR)
- Signal/noise ratio: > 86dB ‚A‘-weighted (XLR)
- Input impedance: 25KΩ (RCA), 50KΩ (XLR)
- Frequency response: +0, –1dB, 10Hz to 100 kHz
- Maximum peak output current: 105 Amps
- Damping factor: 150
- Output devices: 3+3 pairs (bridged arrangement) per channel
Inputs (analogue)
- 4 pairs line level RCA connectors
- 2 pairs line level XLR (balanced) connectors
Inputs (digital)
- 2x Coax S/PDIF up to 24 bit 192kHz
- 2x Optical S/PDIF up to 24 bit 96kHz
- 1x USB B Asynchronous USB up to 24 bit 192kHz
Outputs (analogue)
- 1 pair line level RCA fixed
- 1 pair pre-out RCA variable
- 1 pair line level XLR variable
Outputs (digital)
- 1x Coax S/PDIF up to 24 bit 192kHz
- 1x Optical S/PDIF up to 24 bit 96kHz
General
- Dimensions (WxHxD): 485 x 185 x 510mm
- Max. Consumption: 2000Watts
