JADIS ORCHESTRA

I own a JOR and love it, with the caveat that retubing power tubes requires setting bias voltages usings pots that are inside the unit and I definately rate that job as being not user friendly. The smaller signal tubes can be rolled to your preference and do not require bias adjustments. The unit sounds stellar on my Harmon Kardon Sixty's, but only average trying to push my Martin Logan SL3's. Give the Jadis an easy load and you should be quite happy with the sound. A qualified tech should be able to fix the cap without difficulty (and bias the output tubes) and there should be several in your area who might service tubed guitar amps for local proffesionals. Happy listening,

As there are two connections, my guess is that the cap didn't just fall out because of a bad solder joint (do you see the tabs on it?). You'll most likely need to purchase a replacement 470 uF cap, and have it soldered in, while removing the remnants of the one you described. There are two sets of them, each with two 470 uF caps, bypassed with 150 kOhm resistors that make up the filtering for the B+ voltage.

The Orchestra and Orchestra Reference are the same circuit. The JOR has more upscale cosmetics (faceplate/knobs) and binding posts, the potted transformers, and can run larger (6550, KT88, and KT90) tubes, though I feel they sound best with EL34 variants.

As McFarland mentioned, it's a darned good amp. Though the lowest on the Jadis totem pole, with a friendly loudspeaker, it'll meet the measure of the better products from most companies. I sold my first to a good friend here with a truly upscale main system for use in his office system. I was real gunshy about the sale, as he was obviously blessed (or cursed) with a great ear/taste, and had gone through many products in his search. He was immediately wowed by the JOR. So much so that within a short time, he sold it and moved up to a DA88S. That's as strong a statement about a product as one can make. I ended up missing mine so much that even after buying a DA30 and DA60, I wound up getting another JOR.

Thanks to you all,
Just the solder joint I think.The two tabs are still there. I took the amp to a retired person,he was recommended to me by a hi fi exchange shop. He thinks it was a cost cutting measure and poor design that led to the the cap being dislodged. Which tubes would you recommend I run on this amp? I was planning on running KT88 to get a little more bass and drive my old ProAc super towers.I have 6CA7 and 2A7EH?? I think.Should I upgrade the binding post or anything else? I am not worried about the cosmetics just the sonics. Thanks to you all.

I am the good friend of Trelja, alluded to. He is correct that I was wowed by the sound, although he is too modest to say that he was technically proficient enough to manually bias it, somethinhg I was uncomfortable doing. So, unless you are comfortable in the innards of a French design, get your consultant to bias the amp. On Joe's recommendation, I tried and liked best JJ Tesla Blue L34 (EL 34) tubes, easily and inexpensively obtained in matched pairs from Eurotubes.com(great service and hardy, perfectly matched tubes. A great little amp with a very magical midrange with EL 34s. Just the tough biasing process a single negative, best done by a Pro. But I thank Trelja for selling mne the JOR or I would have missed out on a truly unique house sound that is rarely captured by other marques.........

Thank you, Denis, you're too kind. I'll mention that at the time I had the bias procedure only half right. Credit my own stupidity, though I'll warn anyone who sees the documentation that the translation is extremely rough (having gotten to know them over the past year, they apologize incessantly about their poor English), so you might want to contact me if you ever are interested in doing it. I considered posting a youtube video, but out of safety concerns for the end customer, the company requested I do not. I do have to warn folks who are not comfortable with this stuff that the voltages inside the unit are pretty high, so it's better to be safe than sorry.

The bias procedure is not all that difficult, it's the reassembly of the amp that's the headache, as you need to remove both side panels and the bottom plate. Getting them back together right requires time and patience. I used to think that given all the holes on the bottom plate, it would be wise to tap a few more that line up with the bias resistors and potentiometers, which would make bias a quick operation. Instead on mine, I figured out a better way, where I installed the bottom plate on the outside of the side panels. The only issue with that is the bottom feet screwing in, but I installed threaded clips that solved that issue.

Aussiedrummer, you lucked out when it comes to the cap, thank heavens!

You will get more bass with the KT88, and a bit more loudness. I should install a quad in mine to gauge the differences again, as it's been a while. But, I will say that after hearing both tubes, to me, there is no comparison, the JJ E34L is the way to go. As Denis mentioned, with that tube the amp possesses a simply magical midrange, one difficult to find in any product, regardless of price. I also have JJ KT77 and will try them at some point, but I generally do tube comparisons in my DA30, as the cathode bias (Orchestra/JOR is fixed bias) circuit makes everything plug and play - VERY fast. The KT77 are pretty good, and make more low end, but in comparison, I really do miss that midrange. My good friend, Jeff Carder, who builds the incredible sounding CarderSound speakers goes crazy over my DA30 with the E34L, he claims it's the second best amplifier he's ever heard, behind a far more expensive Audio Note. I do agree with him in that there's simply a naturalness present that eludes just about every high-end audio product. Also, little known thus far, but JJ recently introduced a big bottle 6CA7, I'm curious enough to give them a try.

For 12AX7, the best kept secret in high-end audio today is the Shuguang triple mica 12AX7B. Just about a week ago, another gentleman in Oz tried them out in his JOR based on our correspondence, replacing his EH 12AX7, and could not believe the improvement. I found it impossible to accept at face value, but those Shuguangs really do beat out most of the vaunted old 12AX7 tubes.