Tube covers??

[bsideexperiment]

i went to guitar center recently, and noticed on the back of all the dual rectifiers they had metal tube covers that seemed to go over the preamp tubes. i went home and looked to see if i had them also..just as i expected i didn't have any of them...
i was wandering what these things were, and what they did for the amp?

 

[ylo]

Guitar Center adds these to keep people from stealing the tubes.

No, seriously, they are called shields, and they reduce hum and interference caused by the elements in the tubes picking up induced current from stray electromagnetic fields and radio waves.

You may not notice much difference, but your amp should be a little quieter with the shields put back on the the preamp tubes.

 

[mrt]

Guitar Center adds these to keep people from stealing the tubes.

Thats funny,,,, i saw and wondered the same thing, good to know

 

[Russ]

In addition to what ylo said they protect your tubes from damage like the end of your cord from popping a tube.

 

[Guitarzan]

Noobs....they're funny!

 

[phantomlord2oo]

My Marshall JCM800 has those shield things on them. I need to retube it but I can't figure out how to get the shields off. There aren't any screws that I can see. Am I missing something?

+Mike+

 

[JamesD]

If the shields on the marshall are like the ones on Mesas. All you gotta do is open it like a pill bottle. Push down a little and unscrew it.