Here beginneth a lesson in prejudice. No, not just about my utter, abject, all-consuming, obsessive and nearly psychotic hatred of the French, but about audio prejudices - mine yours. Jadis has created a truly 'high end' pre/power combination of so narrow a focus that we as audiophiles have to search deep into our hearts before even considering reading about them, let alone owning them. In other words, go no further if you refuse to accept that a manufacturer can (and maybe even should) impose restrictive behavioural practices upon the end user. Forget universality, market savvy, commercial appeal, user-friendliness, post-remote control era ergonomics: the JPS8 is aimed at out-of-the-closet masochists.

But is Jadis being unreasonable, for example, for insisting that the system be fully, symmetrically balanced from start to finish, with no single-ended inputs whatsoever, thus eliminating the possibility of using older sources such as non-XLR/balanced phono stages, tuners and CD players? If you say 'Yes, they are unreasonable', then you have to level the same accusation at Naim, Linn, 47 Lab, Croft, Loth X, B&O and a clutch of others, all of which march to their own beat, with their own quirks - the rest of the world be damned. You buy into the programme, or you look elsewhere.

Make no mistake: reviewing the Jadis JPS8 preamplifier and JA50 monoblocks in their fully-balanced forms has not been a piece of cake. True, I had to hand three CD players - the Marantz CD12/DA12, Unison Research Unico CD and Copland CDA822 - with balanced outputs, but I was not able to sample vinyl through the Jadis package, nor to try the Jadis amps with any of my pet single-ended pre-amps nor the Jadis pre-amp with any unbalanced power amps.

Then, there was the little matter of having to swallow my hatred of dual volume controls, a la Croft. Yet again, I cried to the heavens, Why couldn't they fit a simple mechanism to gang the two volume pots together for easy level setting? It wouldn't affect their purist tendencies or the sound or the channel separation. They would remain in unsullied, dual mono form. Oh, no, not Jadis. They want you to have to count each click if you're worried about correct channel balance.

Then, I had to come to grips with the nastiest feel of ANY rotary control I have experienced in 35 years as an audio addict. It was explained to me - and not without a frisson of Gallic sarcasm - that the input selector on the JPS8 is probably the finest, quietest source selector on earth, entirely hand-assembled and, as a glimpse under the lid proved, utterly massive. It could have passed for one of those over-the-top resistor-ladder volume controls the size of a hockey puck. But would it have killed Jadis, with a DNA pool of sybarites, to have damped it in some way? You part with big bucks and you're treated to a rotary control with all the 'feel' of a pre-war, pre-synchromesh gearbox.

If this negativism seems a bit clichÈ'd and predictable, coming as it does from someone who rooted for the assassin in , it is genuinely unavoidable. Why? Because the Jadis system like nothing on earth, and that's meant in the positive. Despite my wanting to hate it - I find, for example, the finger-print magnet of a polished stainless steel finish about as practical as a pair of stiletto heels in a muddy field - the Jadis simply seduces you. If anthropomorphism were applied, the Jadis package would be a Ä5000-a- night French whore.

With its outboard power supply of 5.5x14x9 in (HWD) and a main chassis measuring 5.5x17.75x14in (HWD), the JPS8 pre-amp takes up a fair bit of space. It's all valve, too, so you don't want to crowd it. I used it in 'open space', sitting on a Relaxa 3 platform, with the power supply on the floor behind it. The main chassis weighs 26.4lb, within the Relaxa's capability, with another 19.8lb for the power supply. The latter bears only an on/off toggle and a power LED, which glows green when operating.

It connects to the back of the JPS8 through a professional-grade multi-pin umbilical chord, the power supply's back panel containing only the IEC 3-pin mains input socket, the connector for the umbilical and a holder for a 4A fuse. Inside, purists will be pleased to note that valve regulation means the inclusion of an EF86 valve and - mounted horizontally - a KT90. Also under the lid are three more user-replaceable fuses.

Across the front of the main chassis, in a traditional Jadis gold panel, are an LED which glows red, then green after a full six-minute warm-up, separate left and right volume controls, and the accursed source selector which chooses CD, Tape, Tuner, Aux 1 and Aux 2. (Note that the CD input is padded down to 11.3dB gain while all others have 14.3dB; when reviewing and 'A/B'ing', I used the three players in the Tuner, Aux 1 and Aux 2 inputs to ensure matched gain.) Lastly, there's a toggle switch for muting on/off.

Around the back, all you see beside an earthing tag and the multi-pin socket for the umbilical are three pairs of XLR balanced outputs and five pairs of inputs, corresponding with the source selector. Two of the three pairs of outputs enable the JPS8 to drive two sets of power amps, while the third bypasses the volume controls, so it can be employed for tape out or throughput in a multi-room or home theatre system. Which, given the uber-purist nature of this unit, is highly unlikely ever to happen...

Remove the lid, and it's like a tube crazy's porno mag: 10 of the glowing, phallic babies ensuring dual-mono status and absolutely true balanced operation throughout. (Hey, I was even warned off using adaptors which convert single-ended cables to XLR balanced, hence my inability to play vinyl through the system until I acquire a phono stage with balanced output. By which time the Jadis system will, alas, have been returned.) The unit contains four EL84s, four ECC82s and two ECC83s, with separate gain for each channel's plus and minus, separate output transformers for each channel, that massive source selector wired directly to the inputs, countless high-grade bypass capacitors and high-grade volume pots which, unlike the source selector, have nicely-damped detents. The construction is nothing less than mouth-watering.

A more powerful version of the JA30, the JA50 monoblock is a classic push-pull amp with an overkill, hand-wound output transformer. S.E.T. worshippers will run screaming. Unlike the preamp, which arrived with valves in situ, the JA50 needs its tubes installed by the user. The appropriate spanners are supplied, and it involves only the removal of a cage to access the bases for two EL84s, two ECC83s and two KT90s (or you can specify KT88s or 6550s).

Controls on the front panel include a power on toggle switch, an LED which glows red while in stand-by, and a second toggle to take the unit out of stand-by after 5-10 minutes; the LED will turn green. As this system really does need an hour's warm-up, you soon get used to the long warm-up times required before taking either the power amp out of stand-by, or waiting for the preamp's LED to turn green.

Behind the front panel is the power transformer, a pair of massive capacitors, then the output transformer. Next comes the bank of valves and two more capacitors, and lastly the rear panel with an XLR-only input and two pairs of WBT multi-way binding posts, to facilitate bi-wiring. All of this is housed in a surprising compact chassis, occupying only 7.5x8.25x18.5in (HWD) - but don't crowd it as it pumps out a fair bit of heat. And, despite my reservations about polished stainless steel, it looks sensational.

Operating in pure Class A mode, the JA50 is rated at 50W and can drive speakers from 1-16 ohms. The review pair was set up with the WATT Puppies in mind, but it also saw time with LS3/5As without problem. Input impedance is 100k ohms, bandwidth is stated as 5-29kHz (the pre-amp's is 5-23kHz), and sensitivity is 850mV RMS for rated output.

In addition to the Copland, Marantz and Unison Research CD players and the WATT Puppy System 7 speakers, the only other components used were Siltech Signature and HiDiamond balanced interconnects, and Siltech Signature speaker wire. Comparisons were made with the McIntosh C2200/MC2102 pre/power combination Musical Fidelity Tri-Vista integrated amp and vintage Radfords.

Confession time, something you MUST know if you're to appreciate wholly my response to this equipment: Leading up to listening to the Jadis system was a tortured period during which I actually sent the products back to the distributor, because of my loathing of the French. I write this not for gratuitous effect but just so you'll understand the import of my final verdict. You have to understand that I am an Anglo-American Jew - three cultures so ruefully disrespected by the French that I cannot even bear living as close as I do to Calais. But the Editor appealed to me by pointing out the necessity of being even-handed and professional. Thus, I have betrayed my two nationalities and religion for the cause of hi-fi. But I drew the line at auditioning the products with Edith Piaf.

Once a few teething troubles were solved by Absolute Sounds' inestimable Pedro George-Luis, and I allowed them a long run-in period, I was thrown back to a time when Jadis was a name on everyone's lips. As the brand currently languishes in semi-obscurity, it's easy to forget that less than a decade ago, it was rated as one of the most desirable of high-end brands, especially in the USA. But, like the country in which it is made, Jadis has suffered a fall from greatness. Unlike the country in which it is made, Jadis deserves a comeback. Why? Because the product never stopped being 'great', and it retains its status in markets which seem to have less global influence than the UK and the US, such as Hong Kong and Taiwan.

It's baffling only in that it will sadden those who still believe that a sublime product can transcend fashion, inept distribution, cretinous reviewers, retailers or other non-sonic challenges. It is to the brand's credit that it continues not only to survive despite undeserved tribulations, but to excel in the crowded and competitive field of high-end valve amp production. Even a brief lesson will reveal that the JPS8/JA50 combination is so special as to be breathtaking.

Once the system was warmed up, I sat down with some subtle and delicate recordings, mainly vocal, certainly intimate and - above all - supremely well-recorded so as not to cause distraction. They were as pure as I could find, given my lack of either a phono stage or an open reel tape deck with balanced outputs. The results were not merely staggering. They were revelatory.

I'm as guilty as any of ignoring Jadis; my last hands-on experience was exactly five years ago, when I reviewed their 'budget' range, the Orchestra series. In the interim, I've heard some truly luscious sounds from some of the world's most respected manufacturers. Meanwhile, there was Jadis, producing some of the most luscious of all, a sound as golden as the company's preferred trim colour. Now the lesson has been learned, and I'm deeply embarrassed. This stuff, Gallic origins aside, should not be overlooked.

Take the midband, for starters. You know damned well that no valve amp, however good it may be, will ever match the sphincter-tight bass available from big solid state amps, that Incredible Hulk-grade 'slam' is the province of the transistor. So you think 'horses for courses', and address the prejudices I mentioned in the beginning. If you don't like tubes, look elsewhere. If you bang head, ditto. But if you wallow in vocals - sweet and feminine or textured and masculine - and think that strings are the instruments of the gods and find that nothing tops a good ol' piano for satisfaction from a solo instrument, the Jadis could be your vehicle.

For me, Jadis has redefined the concept of 'intimacy', a session with it being truly <‡ deux>. You hear the 'air', you almost feel a presence. To create this sensation, first the Jadis has to showcase that midband in a convincing space. I've always known Jadis as a brand with a penchant for and skill in recreating three-dimensional soundstages. Whether through the WATT Puppies or the LS3/5As, the Jadis produced an fabulously deep and enveloping stage which extended in front of and behind the speakers in a way reminiscent of Dave Wilson's overhead drawings (in his audio journalist days!), a big fat oval with the speakers in its middle. Feed it a choral group, sans instruments, like Alison Krauss' 'Down To The River To Pray', some King's Singers, the Persuasions, and you have the basis for experiencing one of those 'I can't believe it's not butter', in-the-room events. I dug out vintage doo-wop, Simon & Garfunkel, loads of Temptations. This package doesn't merely handle voices: it caresses them. It is a champion of the midband.

But, you're possibly musing, that's Kessler saying that the frequency extremes suck. Uh, no. The bass, while hardly a match for the Tri-Vista or even the McIntosh, was actually more to my taste; regular readers know that I am not obsessed with weapons-grade lower registers. Clearly, Wilson's Puppies were neither taxed no threatened. Then again, neither was I dissatisfied. Logic suggest that, should you be so enamoured of bass that you need something 'more', you look either to transistors, or to the JA80's bigger brothers (of which there are plenty).

Then there's the treble, that zone where aggravation can be an issue, where softness (as in many other disciplines) can lead to disappointment. It's here that we start talking tubeware, an area where solid state doesn't get a look-in and why valves continue to exist in the 21st Century. The extreme treble is silky or diaphanous as required, yet pin-sharp and precise, too. I'm currently undergoing a Clapton jag and listen to this genius every day. The Jadis handled both his liquid electric guitar playing and his gutbucket acoustic blues with finesse and grace, such that I sat through three discs in a row without even getting up for tea or a pee.

It gets down to this: under duress, I will acknowledge with gun-to-temple that there is probably no better chocolate than Henriet's Rochers de Biarritz and that the most gorgeous cars of all time were made in France in the 1920s and 1930s (but by an ex-pat Italian). It shames me to say this, like Arafat raving about Barenboim, but the JPS8 and JA50 combination is one of the most musical and satisfying pairings I've ever heard, vying with my permanent short-list entries: the all-Nagra package, mint Radfords, Marantz's Project T-1, original Futtermans. Heady company, which almost makes the respective prices - £5900 for the JPS8 and £5890 for a pair of JA50s - seem sensible.

But I'd feel a whole helluva lot better if they were made in the UK or USA.