Fender Blues Junior: Loud buzzing that seems location-dependent

[Vax]

Hey all,

Just need some advice regarding amp noise. My church bought a Fender Blues Junior and we use it in our sanctuary for main services. It seems to have this huge buzz that only goes away if we touch metallic parts of our guitars (grounding problem?), but when we take it out to other parts of the building like the practice rooms, there's no buzz.

Anybody experience this kind of noise problem? Is this a problem of "bad" power in our sanctuary?

Any advice would be useful. Thanks!

 

[Khai HeadrusH]

Is the amp's plug a 2-pin or 3-pin one, bro?

 

[zesn]

Yeah had this problem with almost every other amp i've played on.

Move guitar/body off towards a certain angle away from the amp and the buzz is gone.

Usually it comes with the grounding problem as well, so I suppose it should be a grounding problem. (touching metal parts to stop buzz)

edit: the amp could be sharing "dirty" power with lighting in your sanctuary.
In professional applications, lighting and audio power are separated.

 

[Vax]

Is the amp's plug a 2-pin or 3-pin one, bro?

Bro, it's a 2-pin plug (stock from BGW). You're right, that could help rectify some noise. But even our other amp, a Vox Night Train still has some noise even though the owner changed to 3-pin.

Yeah had this problem with almost every other amp i've played on.

Move guitar/body off towards a certain angle away from the amp and the buzz is gone.

Usually it comes with the grounding problem as well, so I suppose it should be a grounding problem. (touching metal parts to stop buzz)

edit: the amp could be sharing "dirty" power with lighting in your sanctuary.
In professional applications, lighting and audio power are separated.

I see. There are pops and clicks when the light array is turned on/off, so that could be it too. I'm wondering if there's a way to filter the power on stage.

 

[stormage]

Bro changing a two pin to a 3 pin plug doesn't literally solved it, most importantly is that is there any grounding cable within the cable. Usually it is covered in yellow/green insulator. That is the one that grounds the amp circuit.

 

[CyanideJunkie]

Does your church have dimmer lights in your sanctuary hall?

 

[Khai HeadrusH]

Bro, it's a 2-pin plug (stock from BGW). You're right, that could help rectify some noise.

Bro, for ur reading pleasure..

http://www.soft.com.sg/forum/showthread.php?7982-Changing-of-2-pin-plug-to-3-pin-plug(Grounding)

 

[Vax]

Bro changing a two pin to a 3 pin plug doesn't literally solved it, most importantly is that is there any grounding cable within the cable. Usually it is covered in yellow/green insulator. That is the one that grounds the amp circuit.

I'll check out the cable when I do take it out, thanks for the info! If there isn't, I'm kinda hoping that I can replace the whole cable. From what I can see, the cable is kinda permanently fixed onto the amp (not like other amps where we can freely change the power cable).

Does your church have dimmer lights in your sanctuary hall?

If you're referring to lights that have dimming function, yes we do. How does that influence noise?

Bro, for ur reading pleasure..

Hey thanks bro!

 

[zesn]

As mentioned, audio and lighting sharing the same power will affect one another.

So when you dim the spotlights you might hear some noises from the amp, nothing much.

 

[CyanideJunkie]

If you're referring to lights that have dimming function, yes we do. How does that influence noise?

There you go. Most traditional dimmer lights use TRIAC circuits. These are well-known for causing hum problems if not properly isolated.