#1
When i turn on my Fender Deville 4x10 i get a constant static and crackling/popping sound. and occasionally a pretty big Pop that seems to echo through the spring reverb. and its got a pretty bad feedback problem no matter what i do.
any idea what could be wrong?
solutions?
thanks
#2
i would bet money on a microphonic tube, take a pencil, tap each one of your tubes, until you identify the culprit. preamp tubes usually make a little noise, power tubes should make no noise, so if any tube does not match my discription, I would replace that tube
#4
so if i tap it and i dont hear noise from a preamp tube there is a problem with it? and the same if i hear a sound from a power tube?

It is constant. it never ends.
#6
Most tubes will be slightly microphonic, you are looking for one that is particularly worse then the others. Tapping very gently with a pencil is the trick. If tou tap too hard the vibrations can travel through the chassis to the bad one and trick you. Gently is the key. If it's microphonic to the point of causing a fault the slightest tap will come through the speakers.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#8
^ noise coming through the speaker is 'overly' microphonic


yeah, gently is the way

in my vid I kinda tapped to hard. maybe because i was trying to hard to demonstrate something but you can clearly hear the difference coming from the speakers
#9
ahhh, well i went through and checked them all. gently, harshly, and in between but i didn't hear any noise coming form them other than just the typical static and popping but none of it was from the tapping...
#11
Have you tried simply cleaning the sockets?
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#12
i have not, i should probably try that. Just a rag and gentle wipeing? or compressed air?

also since im on at the moment, could it have anything to do with unbiased poweer tubes? or possible the wrong kind?
#13
Get a can of contact cleaner (Deoxit is a good one but any will do). Spray some liberally on the tube pins and work it in and out of the socket a few times.
Do the same thing for the phono jacks as well while you're at it but use a plug as your applicator.

Unbiased power tubes can make them fail prematurely.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#15
No, it's flammable. Just go to an electronics store and buy a can of contact cleaner, it's cheap.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band