Musical Fidelity Nu-Vista PAS Power Amplifier

Musical Fidelity Nu-Vista PAS Power Amplifier

Based on the excellent Nu-Vista 800 circuit, Nu-Vista PAS takes the Nu-Vista range fully balanced. It features the tried-and-tested Nu-Vista stage with 6S51N nuvistor tubes in a discrete Class A amplifier buffer, followed by a balanced configuration circuit and a balanced-input, high-power, low-distortion output amplifier stage. As a stereo power amp, it sits alongside the higher-power Nu-Vista PAM in Musical Fidelity's PRE/PAS/PAM separates system. As an authorized Musical Fidelity dealer in Toronto, Canada, Vinyl Sound can help you build a Nu-Vista separates system around this power amplifier.

Key Features

• 6S51N nuvistor tubes in a discrete Class A amplifier buffer
• Fully balanced configuration and balanced-input output stage
• Greater than 300W into 8 ohms, 500W into 4 ohms, 1000W peak into 2 ohms
• Based on the TITAN 1000W stage, with separate bulk supply capacitors and one capacitor per output device
• Chokes added for improved supply ripple and pulse current spike reduction
• Biased for over 5W of initial Class A operation before transitioning to Class B
• 5 pairs of high-power, thermally compensated output devices per channel
• Dedicated external power supply (Nu-Vista PAS PSU), housing transformers away from the sensitive amplifier circuits
• 4 fully independent inputs (2x RCA, 2x XLR), 2 loop-through outputs (1x RCA, 1x XLR)
• Trigger input and output
• Massive extruded-aluminium front and side panels

TITAN-Derived Power Stage

The power stage is based on the TITAN 1000W design, using separate capacitors for bulk supply plus one dedicated capacitor per output device, reducing output impedance and improving dynamics. Chokes are added for further ripple and pulse current spike reduction. Bias is set for more than 5W of initial Class A operation, after which the stage transitions into Class B at a point Musical Fidelity states is easier to manage than standard crossover distortion.

Dedicated External Power Supply

Nu-Vista PAS ships with its own dedicated Nu-Vista PAS PSU. Moving the AC mains power supply out of the main chassis and into its own matching box frees up space for built-in mains and output filtering, quietening the supply and reducing mains-borne artefacts reaching the sensitive audio circuitry — it also keeps transformers, which generate mechanical vibration and radiate electromagnetic fields, as far as possible from the critical amplifier circuits. The external supply has ON/Standby LEDs controlled from the main unit's front panel, plus a rear-mounted mechanical rocker switch for full mains isolation.

Nuvistor Tubes

Nuvistor tubes were invented in the 1950s to solve the shortcomings of conventional tubes, offering high reliability, low microphony, low noise, batch-to-batch consistency, small size, and low power consumption. They saw limited but notable use in studio equipment of the era, including the Ampex MR-70 tape recorder and the AKG/Norelco C12a and Neumann U47 studio microphones. The transistor's invention largely ended further development of nuvistors until Musical Fidelity created its first Nu-Vista series around fifteen years ago — a limited edition that sold out within months and now commands high secondhand prices.

Reviews

"These heavyweight Nu-Vista amps deliver an impression of unburstable power and resolution, the sound imbued with great clarity, detail, and confidence, even at very high basic playback levels." — Editors, Hi-Fi Choice, April 2023

"The Nu-Vistas made for a spectacular experience, the likes of which I have rarely experienced even with the tube amplifiers that often set the standard in this discipline." — Michael Lang, Stereo, April 2023

"MF's flagship amps are simply sublime. Oodles of power, imaging and separation to die for, with a delicious layer of valvey sweetness that makes their premium price a comparative bargain." — Editors, Audiograde, December 2023

"The Nu-Vista PAS amplifier is also a forthright musical delivery champ. It's direct, and ballsy and powerful. It will provide all the nuance and detail that's in the music, no matter the format." — Edgar Kramer, Soundstage! Australia, October 2023

"I have rarely heard such a combination that pleased me so much with its sense of rhythm. You feel immersed in the musical message — unrivaled in this price range." — Editors, Audio-2G, February 2023

"…the sound I have is just about as open and clear and resolving as any I've experienced in my listening room." — Simon Wilce, HiFi Music and Source, November 2023

"Nu-Vista is techie madness captured in solid form — few things look this uncompromisingly industrial and robust. The sound is so big, authentic and undistorted." — Daniel Březina, Hifi-Voice, March 2024

"The PRE/PAS is parametrically the most perfect hybrid amplifier we have tested. And one of the best in every category. Powerful and accurate, smooth and dynamic." — Editors, Audio Poland, January 2026

"There was no hint of component coloration, as if the music existed independently. The ability of a kilowatt amplifier to produce such fine sound structures is extremely rare." — Nikolay Efremov, Salon AudioVideo, May 2026

Technical Specifications

Frequently Asked Questions

Does this include the power supply?
Yes, Nu-Vista PAS ships together with its dedicated Nu-Vista PAS PSU as a two-chassis system, controlled from the main unit's front panel.

How does this compare to the Nu-Vista PAM?
Nu-Vista PAM is a bridged design delivering over 600W into 8 ohms with 2x 5 pairs of output devices per channel. Nu-Vista PAS is a standard stereo design delivering over 300W into 8 ohms with 5 pairs of output devices per channel — otherwise sharing the same TITAN-derived power stage and nuvistor buffer.

What is this designed to pair with?
Nu-Vista PAS is part of Musical Fidelity's PRE/PAS/PAM separates system, designed to pair with the corresponding Nu-Vista preamp and source components for a full separates system.