PrimaLuna Prologue Eight CD player review

PrimaLuna is one of several manufacturers to have wholeheartedly adopted the principle of designing in Europe and manufacturing in China.

The company is based in Holland and specialises in valve equipment, which it divides into two ranges, Prologue, and the rather more upmarket Dialogue.

The Prologue models share a case design, which must help keep costs down and partly explains the rather untypical dimensions of this unit.

Unusual design

The other part of the explanation is the use of valves. Small-signal valves in the output of a CD player are nothing new, but most are physically small and will fit in a much lower-profile case than this.

PrimaLuna has gone one further, though, and included valve rectifiers, which are considerably larger bottles. Until recently, valve rectification was strictly the stuff of deep, retro, kit-built electronics, but renewed production of the relevant valves has brought it back in to the real world.

It is claimed to be worth the extra trouble (and it's a lot of trouble, necessitating extra transformer windings for a start, never mind the extra space, valve sockets, etc.) because valve rectifiers typically produce less switching noise than solid-state types, reducing internal interference.

Even more surprising than that, though, is a valve in the digital section of this CD player. PrimaLuna claims this is a first and we've certainly no memory of it being done before in any production CD player. Although one might ask, just what can a single valve contribute in a digital circuit with its hundreds and thousands of switching elements?

Master oscillator

The answer is that the valve in question, a tiny single triode concealed deep inside the player, forms the heart of the master oscillator, which controls the digital-to-analogue conversion process.

PrimaLuna has an interesting justification for this, which is that transistor oscillators can contribute phase noise (jitter, in everyday audio parlance) because the transistors used have more bandwidth than is required to make the oscillator work.

We're not absolutely convinced by this, since any well-behaved reference oscillator owes almost its entire performance to the passive component(s) at its heart – a crystal, in this and almost every CD player – but by the same token there's no reason to assume the valve won't work very well in its novel application.

Apart from the listening, of course, the proof of this should be in the jitter, which PrimaLuna claims is particularly good by current CD player standards: again, we can't entirely concur, but only because many CD players in current production have such good jitter as to be practically unmeasurable.

Sound limits

The transport chosen by PrimaLuna is an audio-only one, which gives the player quick loading and mechanically quiet operation.

The valves sit above it, while the rest of the audio circuit is beneath the rear enclosure, which houses the mains transformer. It's not all valve electronics, either – the critical digital-to-analogue converter chip is a modern part and it is connected to an asynchronous sample rate converter, while the analogue filter stage uses op-amps.

These are the once-derided 5534, an audio veteran dating from the 1970s, which ten years ago was completely out of fashion in upmarket audio, but is now back on the shopping list for many designers.

That said, PrimaLuna doesn't claim that the 5534 is the ultimate in anything and has taken another unique step in making available an op-amp upgrade board. This is particularly clever: the (four) op-amps in the Prologue Eight, mounted in a line, in sockets.

Strong build quality

To fit the upgrade board, simply pull each op-amp from its socket and plug the upgrade in their place – it fits neatly into all four sockets and substitutes higher performance op-amps, offering lower noise and higher speed.

The Prologue Eight's build quality is good, but the company has fallen into a trap of its own making with the rear enclosure, which is given a very high-gloss finish.

Unfortunately, this shows up the minutest ripple in the underlying material. All the same, it's a smart piece of kit and the very luxurious all-metal remote control in no way lowers the tone.

More appeal than accuracy

Distinctive-sounding CD players are rare and one might choose to be absolutist and claim that as a blessing: either they're accurate or they're distorted and we're confident that most these days are accurate in very large measure.

In that case, we have to admit that the Prologue Eight is not the most accurate player we've heard. But on the other hand, it is one of the most appealing.

Obviously, the degree of inaccuracy must be small and its type harmless, for the sound to be in any way acceptable to more than a handful of listeners. And that's certainly what is going on here.

We don't want to suggest that the Prologue Eight is wildly off-beam, but there is just enough character about it to set it apart from the crowd and make it more than just another nice neutral player.

In terms of the basics, it does a straight enough job. The bass is strong and clear with good extension.

Much the same could be said of the treble, while the midrange has just a hint of lift in the lower presence region, which very slightly favours female voice over male and violins over cellos. There's nothing particularly distracting, though, in anything but a direct comparison with other CD players.

Nice image

There's pretty good detail on offer and some very nice stereo imaging, too. The distinctive bit starts when one gets into a rather more prolonged listening session. For one thing, this is a subtly more rhythmic CD player than most.

It's not quite as overt a rhythm king as classic Naim components, for instance, so one wouldn't necessarily notice at once, but after a little while one becomes aware that foot-tapping and air guitar have entered the picture and one may feel the need to tweak the volume upwards by half a notch or so, not to make up for anything missing from the sound, but because it's an unusually large amount of fun.

A change of perspective

Not all music has a strong rhythm for a component such as this to maximise, but the Prologue Eight has other tricks up its sleeve. In classical music, it slightly adjusts the usual perspective on the music, bringing the performers into rather sharper focus than usual.

This isn't unequivocally a good thing, though, as it can slightly reduce the homogeneity of an orchestra, making each player more of an island rather than a contributing part of a whole.

On the other hand, it suits chamber works very well, especially large ones such as Mendelssohn's Octet, for instance, where homogeneity is not so much the name of the game.

Here, the importance of each player's contribution becomes clear and the overall result has a great feeling of presence.

Use the musical force

Things are nearest to the 'conventional' version when simple musical forces are involved and you won't quickly spot any great differences with simply accompanied voice, for instance.

Solo piano is solid and believable, but not subject to remarkable new insights, while brighter instruments like violin seem a shade more present, perhaps a little further forward of the loudspeakers, but otherwise unsurprising.

To the extent that there is a downside, it's in the finest analytical detail of the music. If listening deep into the mix, digging out the subtlest difference between alternative takes, for instance, floats your boat, you may find this not the best player in the world.

There's sometimes a little haze around the sound which reduces detail just a touch, but on balance we suspect most listeners will overlook that in the general enjoyment that this fine piece of audio electronics brings to any party.