Vh4 strange rumor/vibration

[bronz79]

Today i've noticed a little but strange rumor/vibration coming from the chassis
of my vh4 2008.
Serial number:080955.

This sound is noticeable in the clean clannel and of course amplified in the 3/4
channels more in the bass spectrum.
I hear this in the attack of the picking more on palm mutes on low strings
and this sound seems to come from near the power transformer.
As i said it is present in the attack of the picking and follow the sound.
What can cause this?

 

[Joeytpg]

I'm 99.9% sure it's one of the screws holding the back pannel hehehe

I had the same problem, well still have, but I took the back pannel off (it's easier to change tubes anyways). I bought my VH4 used and it seems someone changed the factory screws and added some that are smaller so they don't have the same tight grip the originals have (My Einstein had big as screws that fitted perfectly).

so don't worry and check which screw is loose. Could be from the front pannel too.

 

[bronz79]

I'm 99.9% sure it's one of the screws holding the back pannel hehehe

I had the same problem, well still have, but I took the back pannel off (it's easier to change tubes anyways). I bought my VH4 used and it seems someone changed the factory screws and added some that are smaller so they don't have the same tight grip the originals have (My Einstein had big as screws that fitted perfectly).

so don't worry and check which screw is loose. Could be from the front pannel too.

I've checked all the screws of both pannel..sadly vibrations still exist
and is pretty near the power trasformer.

 

[guitarxtc]

i think is normal to hear vibration on vh4.

 

[boba fett]

i think is normal to hear vibration on vh4.

i dont think so

maybe you can check the screws that hold the output transformer to the chassis?
just my 2 cents...

 

[bronz79]

Thanks to all,problem solved.
Today i've extracted vh4 from the chassis and checked it and the chassis for loose screws,
now sound fine.

The problem happend cause i've placed (in my firend's home) vh4 over a 2x12 all upon a
pooerly made wood support.

Now if i put vh4 on my 4x12 I can hear only the tubes vibrating placing my hear near the ampli-head
palm muting or playing,so it's mechanical tubes noise but nothing to worry about.
If i place v4h not over the speakers is dead quiet.

 

[bronz79]

Sadly vibrations still exist.
The only way to get rid off them is:
1- place the vh4 not over a cabinet.
2- mute with an hand the chassis while playing..of course impossible.

 

[Joeytpg]

place the amp on top of the cab but cut out 4 small (5 " x 5") foam blocks, or some rubber mat. That should solve the prob. easily


by the way, get some bigger screws (not that much bigger though)

 

[bronz79]

Sadly ,no way, the vibration still perxist.
It comes out only on certains notes like C and C diesis.
The preamp and power tubes has no microphonicity.

Make an example..i play on low E string 9 fret clean i hear a little vibration,
more the gain stage added the vibration is no more little..

It doesen't concer the front or rear pannel,their are fixed like stone.

The vibration itself doesen't comes from rear of the amp,i've tested it making
a friend play..hearing from the rear pannel on ch3 i hear only normal mechanical
power tubes noise.

It seems to comes from a zone near the 4 big condensers .

A doubt:maybe a defective hardshell?