I have problem with my Tenor150 - advices welcome

i am experiencing a random waving little high frequency noise in the tweeter of one of my JBL K2S9800, that i tend to believe, comes from my Tenor 150.
Intensity is variable and noise is not always present (usually not there at start and tend to be less present after 4/5 hours).
It is not a uhm (wich is also slightly present).
It does disappear when amp is in mute mode but remains kick and fitting when the amp is in stand alone mode (with no connection to the pre-amp).
Noise has increased in the last days.
When i change the plug orientation noise is migrating from one channel to the other.
Voltage is a stable 240v (with no ground due to the age of the electrical installation)

Thks beforehands for your insights.

I did not get answers from Tenor to the mails sent in the last two months and i understand they have other priorities at the moment but i would really like to have this problem fixed.
Beemer, you must be speaking with past horrors in mind; otherwise, I find it amusing that you would be making such comments about Tenor when some of the expensive gear you own come from a company (Levinson) that recently experienced similar problems. I know, because when Levinson's parent company was undergoing restructuring and the factory was moved, I was selling a Levinson gear of mine at that time. I had a hell of a time trying to confirm warranty and such. Their dealers around the world were of no help as some of them had gear that required repair service and some of them were waiting for their orders, placed months before, to arrive. Contact between the company and its dealers were essentially cut off. In this instance, here's a big company with arguably a long track record for excellent service and reliability experiencing the same problems as Tenor did.

Mqg30, this probably won't help if what Fmpnd suggested is true, but have you tried adjusting your powercords and cables so that they are as free from each other as much as possible? And how loud is this noice? This isn't a case of tube noice right?
Howie brings up a good point. If ONLY a tube is bad (as opposed to a fuse or resistor in the audio board which took out a tube), then it could explain the intermittent noise and why it gets better over time. Clearly, it is in your amp as that explains why the noise occurs even when the preamp is disengaged and stops when the amp is in mute.

If it IS in the audio board, you will hear a distortion in the treble region especially when acoustic piano music is played.

One thing you could try is to get some spare 12AX7s (the tubes at the front of the amp) and swap them out. These are easy to find cheap tubes. Or you could also buy new 6H30s and/or the other tube (I think it is a 6N6P) and replace them all. If it is NOT the tubes, at least you now have a spare set.

It may be worth a try.
Audiogon is definitely a place where you meet both the best and the worst but the best definitely worth it. Thks again for your time and advices.

This being said The Tenor team are very nice persons and i remain confident that they will be able to support me in one way or another. Long life to dreams.
Thanks Mqg30. Glad to help. I talked to Stephan (the main tech at Tenor) last night and I can assure you, they will help get you going again. Stephan is a class act, a staight shooter and all around good guy.

Although I can understand somewhat what the other posters are talking about, the simple matter is that MANY of the high-end manufacturers are smaller niche companies that, if you REALLY had access to their financial picture, you'd realize that we take big risks almost every time we buy high end audio gear. Sure, "caveat emptor" or buyer beware should apply to a certain extent and we should keep our eyes open to the risk of these smaller companies going under (which is inherent in the beast)! But hell, do we really know how stable any company is that we buy products from? Just ask the former 401(k) holders at Enron!!

My point? VERY few of the high end audio companies out there are what most of us would consider extremely stable.

That said, I am glad I am not surrounded by some of these posters as friends since their level of "compassion" is so darn high!! ;-)
Lots of good points made. I'm glad that Mqg30 will be able to have his Tenor problem attended to.

LOL Fmpnd, Levinson is now based not much more than 30 miles from my home. At this time the only Lev product I have with any warrantee left is my 390S.


Paul :-)