Great review! Thanks! I have very simmilar experiences with the JOR I used to own some time ago. Great amp for the money and lots of music!
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Hello again. I've tried a few different tubes in the JOR, so here's an updated review.
If you need a bit of extra power (as I did), swapping out the KT90s for KT88s improves things noticeably. The qualifications regarding piano and orchestral dynamics no longer apply in my system. In fact the KT88s saved me a sizeable amount, because I had returned to the dealer with every intention of purchasing a demo Defy7 - the latter still sounded as good as a year previously, but impending home renovations saw me vacillate - and as a compromise I thought I'd try new tubes for the JOR. The KT88s frankly saw the JOR produce a sound which I prefer to that of a Defy 7 (heard with a current Jadis preamp). On the advice of Audiogon members, I opted for the JJ brand KT88s - these are said to emphasize the upper bass, and I like this trait - it lends a plushness to orchestral pieces, and a nice full body to piano works; with jazz it can get a little too emphatic, but the JOR has subtle tone controls and these, together with adjustment of the REL sub, generally see things right. Two of these JJKT88s developed a hum, one immediately and the other a week after installation, and thetubestore.com offered replacements, which have been working perfectly for over a month now. Others laud EL34s, including Pierre Gabriel, but the lower power output did not augur well as a match for the Wilsons - no doubt worth a try, however, if your speakers are willing.
With the 12 AX7s I tried four current production types. The long plated JJ803S; Ei Elite gold pins; Electro-Harmonix; and Shuguang, triple mica. The JJs were very disappointing - the mids and upper bass were far too thick for my taste, and worst of all the highs verged on harsh - a week of burn in saw no improvement. The other three were all perfectly listenable, and I imagine preferences here would be solely matters of personal taste. The Eis offer a sound which I found slightly congested, but I could imagine others would find rich - they certainly were not harsh as per the JJs; the EHs were very clear and smooth, while my favourites remain the Shuguangs, which seem to add a little warmth while retaining the EHs clarity.
I spoke to Pierre Gabriel, calling at midnight Sydney time (10am Canadian time) and he was very helpful and incredibly enthusiastic - he mentioned that most people hold the misconception that the JOR has a passive pre-amplifier stage, whereas it is active and, surprisingly, it is solid-state - there is a single transistor in the signal path for each channel. He did imply that the JOR, while excellent, does sound different in tone to the other Jadis amps. He also described the SE version, which has KT88s fitted as standard, along with some internal changes - including silver wiring. He waxed lyrical regarding the Jadis range of CD players...in the end I had to bid him au revoir...he was only warming up, but I had to go to sleep!
Overall the change in tubes has, for me, only improved an already terrific amplifier. A year on I'd recommend the JOR still more unreservedly.
Nice review - Thanks for sharing your time. I am familiar with some different models od Jadis (by that I mean owned them), and currently having great results with a DA50 Signature driving my Avantgarde UNOs, which has been the best amp for these speakers from over a dozen I have tried and/or owned before.
Might be interesting in your upgrade options to consider it, since it is a gem.
I have the orchestra reference purchased from Pierre Gabriel and love it. The EL 34s that came with it burned out and I was considering replacing them with something else. I was thinking 6550s or KT88s for better bass. I am using high sensitivity speakers - cabasse farellas which I was told are a great match for this amp - so I wonder what your opinion of choice of tube is.
Great review. I own one of these amps, with brand new KT90 tubes this week now, for a while and playing it on Dali Helicon 400 speakers.
The sources I use are Jadis Symphonia CD-player and VPI Scout with Benz-Micro Ace low output with Acoustech PH-1.
My expiriences are very similar with the amp but with my speakers in a small 4 by 6 meters room I have more than enough bass and power to drive the music as loud as the live sessions.
I now listen to a live consert of Joe Satriani, witch I have heard a jear ago for real, at about 105Db on the Radio Chack SPL meter and it sounds like I remember from the real concert. Fast, deep hard bass and realy fast guitar riffs.
I realy like this amp on my speakers now and don't want another amp for now.
Recently, the KT88s have made way for JJ KT77s. There is a noticeable difference. The upper bass bloom and density have disappeared. Bass weight is still there, but detail has been improved. This 'cleaning up' of the upper bass has in turn made the midrange more accessible - I hesitate to say that it is in any way sweeter (I think the character is reasonably similar), but without the widely reported JJKT88 accentuation of the upper bass the clarity of midrange is certainly more evident. Highs, to my ears, remain much the same.
Overall the effect of the JJ KT77s is to add definition and detail. However, there is a cost in that the 'colour' of the presentation is lighter and brighter. Whereas the JJ KT88s ask for words such as "full" and "rich", the KT77s peel away the darkness and leave things a little more exposed.
To illustrate with examples from music. John Coltrane's sax on Kind of Blue feels less weighty, a little less like it's about to burst into the room, but then again the nuances of his playing are thrown into higher relief. Glenn Gould's piano from his 1981 Goldberg Variations is rendered with all the more idiosyncracy, its harpsichord like astringency to the fore - there's more precision to the recorded acoustic too and his own grunts, gurgles and groans are, for better or worse, more lifelike; yet the piano also sounds a fraction more distant. Talking Heads remastered Speaking in Tongues is unravelled more effectively into its consituents parts, the various layers of the mix open to inspection.
I feel the altered sound from the 77s invites a looking "into" the music, rather than the JJKT88 effect of wrapping the listener in a cushion of sound.
As you might tell, I'm not sure whether I truly prefer one effect over the other. If pressed, I might say the 77s are more "accurate", but the JJ88s more tube-like. So the head likes the 77s, but the heart has a soft spot for the JJ88s.
Otherwise the JOR remains completely reliable and enjoyable. It's now in a new listening room with a much improved acoustic. Three years on, it has never sounded better, and for any reader contemplating a purchase my recommendation remains unreserved.
FWIW, faced with a similar tone issue as you had with the JJ KT88's (upper bass bloom, etc) in a different amp, I simply changed some of the driver tubes from a brand known for warmth in upper bass and slightly soft highs, to a brand known for clarity and detail. Worked for me. :-) Using the KT77's you might play with the driver tubes a bit and try using some known for warmth to get a bit of that bass bloom back and still keep the clear mid range.
Just a thought.
The JJKT77s have proven to be something of a disaster. I'd read here, and elsewhere, that their reliability was suspect. Several dealers refuse to sell them. My experience confirms these fears. The JOR takes four, but I purchased eight, to have a spare set as back up. Within two months two of the KT77s had "run wild", drawing excess current and burning out - on the second occasion blowing fuses in the amp. During this time three other tubes had begun to crackle or hum. So I was left with three functional tubes out of eight. In two months.
Yes, they sound fine. But who cares when they are this unreliable.
What's more I've since installed Gold Lion KT88s, and Ei gold pins as the 12AX7 drivers, and this combination sounds streets better. The Gold Lions have all the pluses of the JJKT88s I had previously, with the additional benefit of much more extended and detailed bass. The midrange, probably the JOR's greatest strength, is utterly sublime with this complement of tubes. The highs are liquid and alive. But the bass is the real surprise - there's growl and bite in electric bass runs where previously there was only a steady solid sound; acoustic bass has that extra definition that creates the illusion of the instrument being in the room.
I'm currently using the JOR with Wilson CUBs, but no sub, and an OPPO 980 universal player - the punch and depth of sound is just great fun. In another room there's an ARC CD1, SP9MkIII, and a Wyred4sound ST 1000 putting out 600+ watts per channel into a pair of Usher Be718s, and a REL Storm III, and while this system has outstanding transparency in the mid and higher frequencies, and is completely non-fatiguing, it loses out to the Jadis/Wilson combo for that upper bass drive that makes some music come alive. (The second system has been set up for use with a video projector, the two channel sound being fine as we mostly watch old (mono) films.)
I purchased my JOR around 2005, with reduced power in the right channel. Note to readers, watch out for reduced power in one channel -- could be a tube, could be an output transformer. More on this to follow below.
The JOR sets up the output tubes at 525v on the plates, which has good and bad things to it. It's at the top end of the rating for EL34s or KT88s, and in the comfortable range for KT90s. When a tube is run at high voltage, it might last a little less long, and if it fails, it tends to make more smoke and take more things along with it, in my experience. Vibration is an anathema to lightly suspended grids, carrying very high voltages not far from ground potential (the cathode).
Speaking of tubes, the KT90s I have tried so