Valves were masters of the electronic world for a relatively short time before being superseded by transistors. The first transistor was successfully demonstrated in 1947 at Bell Laboratories, and by the 1950s it already felt like good old thermionic valves were in their twilight years. But there was one last-ditch attempt at fashioning an ultra-reliable vacuum valve, a design which would deliver the very best measured performance yet avoid glass-based microphony and delicacy. This led to RCA’s introduction of a metal-cased ceramic ‘nuvistor’ valve in 1959.
The nuvistors looked rather dull — no glowing filament within glass here — but they were stellar performers, proved almost indestructible, and were long-lasting too.
No-one makes them anymore, so it comes as a bit of a surprise that Musical Fidelity has announced a three-strong Nu-Vista separates range that uses them. It seems the British brand still has a stash that it's dipping into here!
The new models are the Nu-Vista PRE pre-amplifier, Nu-Vista PAS stereo power amplifier, and Nu-Vista PAM monoblock power amplifier. These all-analogue amps have been designed from the ground up, with their nuvistor valves complemented by fully balanced discrete circuitry and extensive connectivity.
The Nu-Vista PRE and PAS are both Class A designs with eight (four per channel) 6S51N nuvistors in the buer stage. The PRE also has a pair of mini power amps operating in Class A and outputting around 50W.
The pre-amp has 12 inputs in total — six line-level RCA and six fully balanced XLR connections — and its RCA and XLR outputs come in fixed and variable options. Additionally, the PRE has a +6dB gain boost button to help with system matching — it also cleverly remembers which input needs this feature.
The Nu-Vista PAS power amp has a high-power (300W into eight ohms) output stage, with five thermally compensated output devices per channel for more stable operation. It further takes inspiration from Musical Fidelity’s iconic Titan amplifier by having separate capacitors for the bulk supply — one each for the output devices. This, it says, claims to reduce output impedance and thus improve dynamics.
The power amp features two line-level RCA inputs, two balanced XLR inputs, and single fixed RCA and XLR outputs.
The PAM monoblock eectively separates the PAS power amp into two modules for those who want (and can aord) better channel separation. The PAM benefits from a modified internal design thanks to the extra space, with a bridged output amplifier stage using two pairs of high-power, thermally compensated output devices. The result? More power (600W into eight ohms), improved imaging and a greater ability to drive speakers, says Musical Fidelity.
All Nu-Vista amplifiers come with an outboard power unit (PRE PSU/PAS PSU/PAM PSU) in a matching chassis, keeping the AC mains power supply away from the main unit and consequently removing interference from the main units’ circuits. The PSU units are similar in dimension and weight to the main preamp and power amp units (a hefty 25kg for the PRE, and an even heftier 40kg for the PAS and PAM), so you'll want to make sure you have ample space and support for them before taking the plunge.
The Nu-Vista components sport aluminium chassis (in black or silver) and dimmable VU meters on their front panel. Musical Fidelity naturally claims that build quality befits the models’ five-figure price tags. The Nu-Vista PRE and PAM cost $41,000, while the PAS is $45,000. That’s not it for the new range either; more models will beef it up this year and next. Watch this space.
For more information, contact Audio Marketing on (02) 9882 3877 or visit www.audiomarketing.com.au