Amp/Preamp Asylum

Looking for a new Amp or Preamp? If you're after tubes, post over here.

Return to Amp/Preamp Asylum


Message Sort: Post Order or Asylum Reverse Threaded

So this happened . . . any thoughts on the cause?

76.19.107.199

Posted on July 16, 2022 at 16:31:02
JoshT
Audiophile

Posts: 6517
Location: Eastern Massachusetts
Joined: July 4, 2000
Contributor
  Since:
July 22, 2000
This morning, when I turned on my system, I got no sound at all. After checking all the settings, I realized that the signal tubes in my CJ Premier 11A power amp didn't light up at all. There'd been no "event" that I'm aware of - the amp was fine yesterday but not today. The power tubes continue to light up normally - just not the little ones.

I will reach out to CJ naturally, but any sense of what could cause this? I'm fairly sure it's not fuses or bad tubes (anecdotally), but what do I know?

Thanks in advance for any advice!
___
"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."

 

Hide full thread outline!
    ...
Possibly a fuse. See these photos...., posted on July 16, 2022 at 18:06:03
AbeCollins
Audiophile

Posts: 41448
Location: USA
Joined: June 22, 2001
Contributor
  Since:
February 2, 2002
I found a couple CJ Premier 11a photos on the internet.

There appears to be two fuse sockets on top of the chassis and four fuses in fuse clips under the chassis. The ones up top should be easy to check as I believe the RED LED should light indicating a blown fuse.

You'll have to open the CJ to see the fuses under the chassis.

Check the values and replace with identical fuses or CJ might send a complete set free of charge - ask them.

There wasn't a big difference between the Premier 11 and Premier 11a. According to the schematic it appears that the power tube filaments go directly to the transformer output but the signal tubes are AFTER the fuse and bridge rectifier [for DC on the signal tube filaments]. I suspect the fuse but w/o being there to actually measure with a DMM this is just my best educated guess.

Good luck !!




 

Wow, thanks Abe!, posted on July 16, 2022 at 18:33:14
JoshT
Audiophile

Posts: 6517
Location: Eastern Massachusetts
Joined: July 4, 2000
Contributor
  Since:
July 22, 2000
This is really helpful.

Edit: I'm quite sure it's not the fuses accessible from the top, which I understand are the plate fuses, because I've had them fail before due to a bad tube and they don't cut off the tubes (or even sound, though the sound becomes muted and quiet). Probably the fuse you mention underneath. I'll call CJ to ask.
___
"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."

 

RE: So this happened . . . any thoughts on the cause?, posted on July 17, 2022 at 05:56:12
Blackdog
Manufacturer

Posts: 1505
Location: Ontario
Joined: March 20, 2006
Schematic shows a 4A slow blow fuse in the filament circuit for the preamp tubes.
That's internal, and probably blown.
I've also come across the rectifiers failing, and due to the heat generated bad solder joints on the rectifiers. If it isn't the fuse, then it should go to get serviced.



Dan Santoni

 

Thanks Dan., posted on July 17, 2022 at 19:57:13
JoshT
Audiophile

Posts: 6517
Location: Eastern Massachusetts
Joined: July 4, 2000
Contributor
  Since:
July 22, 2000
Very helpful!
___
"If you are the owner of a new stereophonic system, this record will play with even more brilliant true-to-life fidelity. In short, you can purchase this record with no fear of its becoming obsolete in the future."

 

Page processed in 0.333 seconds.