Preamp tube glow question

[coyoteblue]

I have a Deluxe Reverb and I'm having some problems I'm trying to diagnose. It would help to know if all the preamp tubes should show some red glow if they're working properly. Some of mine don't, and though the sound's ok, I wonder if the lack of glow in some tubes could be a problem. The problem is that a number of my tubes sound microphonic when I lightly tap them, and I have off and on light distortion when I play, especially on bass notes. Tightening the sockets is probably an issue. (Thanks for your help...I've asked this question in a variety of ways in the past week.)

[rockon1]

The heaters in some tubes will be brighter than others. Heck in some tubes such as the Sovtek LPS the heaters cant even be seen!(no glow at all!)

[Witek]

Could be because you might have loose tubes and when you play they vibrate and you get your microphonics. Try tightening up them tube sockets and see if you still have the problem.

That's the best I can do realy.

[coyoteblue]

Witek, what you say about loose sockets creating microphonic problems as they vibrate makes sense. I've found that distorition increases the longer I play.

[Witek]

Do you have covers for these tubes? By this I mean the little shields that you put over the tubes. I know that some of these have springs in them that hold down your tubes better. Those might be a good investment if you can't get your tube sockets any tighter and don't want to replace them.

[Johnny Z]

If they sound mycrophonic when you tap them, you may want replacements, mycrophonics always get worse over time. As far as the sockets, tighten them but also clean them first, and use the tube shields/holders to keep the tubes in place and you won't have as much tube vibration. If the tube heaters weren't working the amp wouldn't work, so don't give than much concern. The distortion may be normal tube tube breakup, 6V6's are great for it when pushed and it always starts with the lower notes. Replacing the power tubes with new ones may cut this down some. Also for less breakup install a 12AT7 in the driver (the 12AX7 tube next to the 6V6's).

[coyoteblue]

This amp comes with metal tube shields, but I don't know that they hold the tube in place...they don't touch the tube. Is tightening the sockets something I can do...a little direction would help. Thanks.