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

Pulsing tube

91.159.5.131
Posted on July 26, 2016 at 02:36:15
Kajtsu
Audiophile

Posts: 84
Joined: December 4, 2005
 Hi all,

I bought new EL84 tubes to my Leak stereo 20 amplifier and now one of the new JJ tubes has pulsing glow. I think the tubes are OK, because I changed places and the result was same. I can hear hum hum noise (volume off) from the left speaker (same channel were the pulsing tube is). Is this dangerous to amplifier and what causes this? With old sovtek tubes this does not happen.

thanks in advance
Kajtsu

 

Hide full thread outline!
    ...
RE: Pulsing tube, posted on July 26, 2016 at 07:00:19
airtime
Audiophile

Posts: 11287
Location: Arizona
Joined: February 4, 2003
 So the tube in one socket pulses regardless of which tube is in it?

Or one tube in particular pulses?

charles

 

RE: Pulsing tube, posted on July 26, 2016 at 08:11:29
FenderLover
 Can you check the idle bias?

 

RE: Pulsing tube, posted on July 26, 2016 at 09:35:39
Kajtsu
Audiophile

Posts: 84
Joined: December 4, 2005
 Hi Charles and Fender Lover

I noticed it stopped pulsing when I changed old Sovtek tubes back.
New JJ tubes are looser than Sovtek´s in the socket. Can this cause problem?
Speaker cone is pumping little but not so much what it pumps when JJ´s are on.

Kajtsu

 

Yes, the pins on those JJ are prolly smaller diameter, posted on July 26, 2016 at 11:34:28
FenderLover
 You'd need to tighten the sockets a bit, if you continue to use the JJs.

 

Page processed in 0.017 seconds.

[ Top Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]
[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]