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Conrad Johnson Premier 17LS preamp shuts off

Hello,

I am a happy owner of a C/J amp system (also includes a Premier 140 amplifier). However, since the very beginning of the life of my system I have experienced issues with the power shutting off after a while. I had the system repaired at a shop here in Paris, but after a couple of years the power started getting off again. Usually the led lights are also affected and start to blink and lose strength. Now it won't turn on again for even a short time.

I tried several things including earthing the chassis of the preamp with no satisying results.

The system is seven years old (but that might not matter much, given that the problem occurred pretty early). We use it moderately (very other day we might listen to a couple of CDs). It also has a very low hum (we can barely hear it).

Any help would be greatly appreciated. At least I could steer the repair shop towards a more durable solution...

Regards,
Antonio
acazorzi
marakanetz's avatar
marakanetz
5,473 posts
 
hum is ok. the shut down is probably due to the unstable power. do you have any power conditioner with voltmeter so you can trace fluctuations?
onemug
784 posts
 
Couple thoughts:

Either you or your repair shop email CJ and ask them.

When is the last time you replaced the tubes?

How stable is your a/c delivery? It only takes a fraction of a second to cause problems with the microchip circuitry.

Nice preamp. Hope you get it fixed properly.
acazorzi OP
3 posts
 
Hi, thanks for the quick reply. Sorry for repeating the thread: I thought the first post hadn't gone through.

So far I haven't replaced the tubes. I am sure it is about time, but the issue has appeared very soon.

I am not sure about the a/c delivery here in Paris, but I guess it should not be that bad. I don't have a power conditioner. I am not sure it is linked to the power though: the troubke has gotten worst while the power is probably stable... After a temporary fix by a local shop which did not last more than two years, the issue started to appear again and became more an more frequent. I tried to earth the box with no results.

I thought it might be some electrostatic effect... Can it be?

I will send a mail to CJ. I guess they will ask to contact the local shop here...

Regards,
Antonio
invenio78
33 posts
 
I agree with the other commentators that you need to make sure the power is good. I would definitely try with a good power conditioner (and voltage regulator).

Also, has the unit ever been exposed to too much electricity such as a lightning storm. On conradjohnsonowners.com there was a story of a person who had electrical damage done to his CJ unit due to a storm and it was unrepairable. Perhaps something like this may have happened that damaged the electronics, perhaps in the on/off circuit if that is the problem your having?

I would probably give Ed a call at Conrad Johnson, he is very helpful.
acazorzi OP
3 posts
 
Thanks invenio78. I will definitely have a chat with Ed. I also remember him as being very helpful.
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