Preamp Tube Caps

[diesel389]

Is there any functional purpose for these caps? I just noticed that a couple of them were loose and were screwing up my effects loop. V1 is really hard to get the tube/cap on (unless you take out the chassis) because it's behind the transformer. Would it be bad for any reason to leave the cap off the first preamp tube?

Thanks

jp

 

[mesaboogie6L6]

If you are preferring to the metal shields, they are designed to cut down on noise and interference. Some people don't use them, guess you could take them off and see what happens.

http://www.wisegeek.com/what-is-a-tube-shield.htm

 

[Addictedtokaos]

They will only work properly (reduce noise) if grounded. Grab a multimeter and set it on continuity. Clip one end to metal on the amp chassis. Now put the tube shield on and test for continuity with the other probe by touching it on the cap.

If you dont get a good ground try turning the cap until you do. Once you get a ground then the cap will work as intended. Repeat for all caps and you may want to mark on the cap with a sharpie so you know where you get a good ground connection.

 

[diesel389]

For some reason with the caps on I'm getting a slight drop in output when my effects loop is engaged. I tested without the caps on everything was spot on. Debating on keeping the caps off due to this. Any final thoughts before my next band practice (thursday)? Cheers,

jp

 

[deeman]

That sounds strange to me but whatever works for you I guess. I don't think it'll hurt the amp any to run it like that.