Amp buzz when I hit a particular note

[faizal_rocks]

Hi all

Just got a Fender Frontman 25R amp..my 2nd time owning it n when playing an F# note on different frets, the amp buzzes..like there`s some rattling in the amp..why so, eh? Is this normal?

 

[gjkung]

that is called resonance I believe.

There's a certain part of the amp that's loose, like the metal grill for example, and it has a natural frequency that's similar to an F#, or is harmonically similar. So when your amp cone vibrates, it resonates and vibrates too, causing rattling.

http://en.wikipedia.org/wiki/Resonance#String_resonance_in_music_instruments

that should help.