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
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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 clich 'd and predictable, coming as it does from someone who rooted for the assassin in
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.
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