what is the most likely cause of crackling, popping noise in a tube amp for the first minute or two after start-up. This noise is audible but by no means loud and stops after a couple of minutes.
Thanks
Thanks
4 posters
noise in power amp
Bob Latino- Admin
- Posts : 3276
Join date : 2008-11-26
Location : Massachusetts
Hi Bizi,
It sounds like a tube issue to me. Try swapping out some newer tubes or some tube known NOT to cause this issue. Is it in both channels ? OR just ONE channel ?
If you said that this happens after a half hour or so I might have said a problem on the driver board - a bad solder trace that goes thermal and opens up.
Try swapping out some tubes and let us know what you find ? If you don't have any other tubes try swapping tubes between channels. While your at it clean off the tube pins. Contrary to what some say you CAN use WD40 to clean off tube pins - just wipe it all off before you reinsert the tube. This tube pin issue is more likely to come up on small 9 pin signal tubes like a 7199, 12AX7, EL84 etc. than a larger octal tube which has more pin area to make contact with the socket pins.
Bob
It sounds like a tube issue to me. Try swapping out some newer tubes or some tube known NOT to cause this issue. Is it in both channels ? OR just ONE channel ?
If you said that this happens after a half hour or so I might have said a problem on the driver board - a bad solder trace that goes thermal and opens up.
Try swapping out some tubes and let us know what you find ? If you don't have any other tubes try swapping tubes between channels. While your at it clean off the tube pins. Contrary to what some say you CAN use WD40 to clean off tube pins - just wipe it all off before you reinsert the tube. This tube pin issue is more likely to come up on small 9 pin signal tubes like a 7199, 12AX7, EL84 etc. than a larger octal tube which has more pin area to make contact with the socket pins.
Bob
danf- Posts : 58
Join date : 2009-01-19
bizi- Posts : 7
Join date : 2009-01-23
Thanks for the feedback. In fact it was a noisy output tube and nothing more.
Bill
Bill
Tube Nube- Posts : 707
Join date : 2008-12-06
Age : 61
Location : Calgary, AB
I have a slight static sound, a few seconds after I turn the power on, and it lasts for about 5 seconds. Maybe 10.
Both with the Dynaco, and again with the Transcendent pre amp, if I turn it on second. Because it happens with both, I'm just assuming that it's normal for tube gear to make a bit of noise as the tubes come to life.
Alternately, because it's both amps that I assembled myself... ahhh, maybe my technique leaves something to be desired. :-/
I wonder if I should be concerned, and start swapping tubes around, or can someone comment if this is normal.
Thanks,
Brenton
Both with the Dynaco, and again with the Transcendent pre amp, if I turn it on second. Because it happens with both, I'm just assuming that it's normal for tube gear to make a bit of noise as the tubes come to life.
Alternately, because it's both amps that I assembled myself... ahhh, maybe my technique leaves something to be desired. :-/
I wonder if I should be concerned, and start swapping tubes around, or can someone comment if this is normal.
Thanks,
Brenton
Bob Latino- Admin
- Posts : 3276
Join date : 2008-11-26
Location : Massachusetts
Brenton,
Sometimes tubes do make a few sounds upon startup. If both units play OK after warmup I wouldn't worry about it ...
Bob
Sometimes tubes do make a few sounds upon startup. If both units play OK after warmup I wouldn't worry about it ...
Bob
Tube Nube- Posts : 707
Join date : 2008-12-06
Age : 61
Location : Calgary, AB
Thanks Bob.
They sure do play well!
They sure do play well!