I do not know how to bias my JOR if at all possible.
Never cared for flat toned sound, so I place the trebel and bass controls 95% gain. If I put the controls all the way up, I get a slight hum.
My Jadis are driving prefectly the Thor's. A pretty hefty MTM design, rated very low at like 87db. I hae no issues with loudness.
I recall when I first got the Jadis, I took it to a friends house, his ARC 200 and Mirage 1's, a big hefty 3 way. He agree the Jadis outperformed his ARC is clarity/details. But of course the big ARC 200 took the little Jadis is terms of power.
I suggest looking for another speaker, amybe a Tyler or a bigger amp, maybe the Cayin A88.
I do not think it was possible to use the Jadis as amp, over ride the pre.
Paul |
I have a JOR and have driven everything from Quad ESL 63's, Spendor SP100's, Rogers LS 3/5a (15 ohm) and various Sololiquy floor standers with it, and to some pretty good volume levels, with no trouble at all. Actually amazingly strong tight base and overall delicate articulate sound. I use the KT 90 tubes normally in it. |
Bbro's experience with the Jadis certainly attests to the power offered in the smallest of Jadis amps. My friend with the big hefty ARC VTL200 was quite impressed that the Jadis delivered a much better sound vs his big amp/pre. Though we both agreed its not ideal for the Jadis to drive big speakers.
I'm surprised the Jadis holds up under Bbro's relentless punishment.
Any other amp would have broken down. Especially any other medium size tube amp. One buys the JOR not only for sound quality but also for its superior build quality.
The only reason I'm going with the Cayin A88 is for that extra 5% I'm hoping the Cayin will offer.
5% is alot in audio.
However the Jadis will stay in the family. |
I would probably ask Pierre Gabriel or Jadis the question. If you don't have pre-out/amp in jacks on the back, you probably couldn't do this without major surgery. What output tubes do you use in the JOR? You might try KT88s, if you're using EL-34s, you lose a little midrange magic but get a bit more power. I'd choose them over KT90s or 6550s. |
Yes that is what Richard Grey told me, that it would be major tweaking to supply a preout.
Richard did say the KT90's add abit more bass over the 88's.
I'm not going to switch tubes, just seems a better option is to upgrade to the Cayin. I mean whats a good pre going to cost you? 1K? Throw in another 500 and you get the beefer Cayin.
Makes more sense to me. |
I have a JOR and gave it to my wife. The JOR has a PASSIVE pre-amp section with no gain. I used a Rotel tuner/pre-amp so that she can have the convenience of remote control. I have the JOR's gain control at about 10 or 11 O'Clock, if that helps you. Everything seems to work just fine and has been for several years in this set up, driving Triangle Titus's. The CD player plugs into the Rotel, so that the Rotels remote controls everything except power on and off. |
I assumed that since the pre-amp section is passive, all the volume control is doing is decreasing output by adding resistance - put the volume control on full gain and the JOR is basically operating as a power amp: if this is incorrect, please let me know.
An active pre-amp presumably amplifies the source signal to some degree, but I am unsure whether this translates to an easier time for the JOR - also whether the amplified signal is actually going to put a strain on the JOR input circuitry.
The distortion is really only limited to passages of classical music, generally solo piano, where virtual silence is followed by fff chords. The Wilson speakers dip to below 3 Ohms, and this, apparently, is the cause of the difficulty. The previous 110Wpc ARC D125 had no problems with the above.
At the moment I am not in a position to change speakers. I just happen to have kept my ARC pre-amp so adding it in would be simple and pragmatic, if indeed this is possible.
Any further comments would be welcome. Cheers,Rob. |
Bezimienny, I believe Russ (Rcprince) asks the relevant question - what output tubes are you using? If you are using the EL34, you will gain a bit more extension using KT88.
Next question, when was the last time you biased the JOR? As the tubes age, I found the bias settings must be inched up accordingly.
Also, are your output tubes fresh? After 6 years with the Ei KT90, I had one short (causing no damage to amp or speakers), and I had to account for it by really pushing that channel harder. It wasn't until after I got a tube tester did I realize what the true problem was.
Biasing is of critical importance with the JOR, and a guy I met here in the threads was having a lot of problems with his. Lots of distortion and a crackling sound. Turns out the problem was the amp needed to be biased, and my original instructions he was using were not correct for all of the tubes. After he sent it to Avi Brand (US Service rep), everything was fine. I called Avi to confirm the correct bias procedures.
If you are using the Ei KT90 or a KT88, and the JOR is properly biased, then the amp needs an easier load to drive than your Wilson Cubs.
Paul, you are using the JOR with the tone controls at 95%??? I found if you go past 25% either way from flat, it SERIOUSLY alters the sound for the worse, completely changing the character of the JOR. Not that my flavor is the right one, but I found flat treble, and 10 - 20% more on the bass was often where my comfort zone was. Though I could still hear the deleterious effects of the tone control as compared to flat, the bass boost was welcome. |
I suppose, if the preamp section of the JOR is truly passive (I seem to recall reading somewhere that it might be an active solid-state unit, though, so that's why I'd ask Jadis), you could try your ARC preamp running into the Tape In input (or for that matter, I guess any input) and seeing how it sounds. The losses in transparency might be offset partially by the additional gain. But I'd keep the volume on the ARC very low at first, and gradually build it up, to make sure there's no overload problems. |
Hi Bezimienny. While I haven't tried the JOR I have an integrated with a passive pre section and I have tried exactly what you mention above. Open the volume control full, connect a pre in into whatever input of your choice on the integrated, (obviously make sure you've selected that "source" on the JOR), and voila. I started with the volume off on the pre because I wasn't exactly sure what was going to happen. Anyway, it worked for me. Don't know if it will work for you, caveat emptor, don't try this at home, blah, blah, blah :-)
I was just goofing around and didn't really evaluate the sonic benefits however.
Finally, I have been told that you run the integrated full open and the pre controls volume, not the other way around. If you can borrow a pre to try, just be careful and why not give it a whirl. That's my 2 cents. |
Thanks for the comments. I think the general gist is that while the above is possible, it probably is not a great idea.
Hi Trelja - the JOR has KT90s - the distortion occurred from the get go, that is directly after purchase. In fact one of the factory KT90s developed a (completely different and continuous) crackle a month later and the store owner took it upon himself to change the whole lot and have it rebiased - the distortion on loud piano passages remained, although the unit has been completely trouble free, in terms of any continuous crackles etc, since. I love the sound - it really is just this isolated issue, although it is important in that I listen to solo piano frequently.
To be fair, the sales staff warned me about the JOR struggling with the Wilsons - I auditioned a Defy7MkIV first, along with an ARC VS110 and a Gryphon SS power amp - the Defy was fine, but very expensive; the JOR sounded better than the others. They mentioned the larger Jadis integrated, which I think you own, but they did not have one on hand to audition - it too is very dear here in Australia (and probably elsewhere) - the JOR was one third the price and we have impending home renovations, so I accepted the compromise - and, in the main, a very nice compromise it is.
Cheers, Rob |
Bez, the weak link in your system in not the JOR, it is with these Wilson Cubs. Not sure what apeaker you are refering to, did not see it on wilson's web page.
I heard 3 Wilson models 3 yrs ago in a showroom and was not impressed in any way. One of the worst speakers I've heard.
And "didps below 3 ohms", I can believe it and would never hook anything unfriendly to my JOR.
Let me ask you did you buy your speakers first , THEN the JOR?
You did it backwards. Buy the amp first, then look around for speakers.
Look at Bbro's line of speakers he uded on the JOR. Thats punishment for a little tube amp, yet the JOR worked the load.
The JOR will deliver high dynamics on the right speaker.
In any system, there are 3 sources for coloration/fatigue.
Amp/speakers/cdp. The object is to find the least coloration/distortion in each category.
If one of the 3 is of poor sound, it will drag down the other 2.
Paul |
