Questions about open humbucker cover.

[greekdude]

Re: Questions about open humbucker cover.

Go back and read what you said then read what I said. You will then realize why this reply is a non sequitur.

Also, cover removal wasn't done by designers. It was done by people like Eric Clapton and before there was an aftermarket and the aftermarket is catering to people that like that.

The principal of the design does not involve any particular implementation. You confuse the "principal" with an early prototype. In theory a HB with perfectly balanced coils will cancel out any external noise applied uniformly upon the coils. That's why some HBs are more quiet than others. (e.g. Blaze bridge vs Blaze neck)

 

[beaubrummels]

Re: Questions about open humbucker cover.

Eddy currents swirl perpendicular to the changing magnetic field. The string is magnetized in the same direction as the pole piece, so the eddy currents move around in circle patterns directly below the guitar strings. The currents swirl in the slugs and screws, and if you have a metal cover, then they also swirl in the cover, over the slugs, and around the tops of the fillister screws. The open top covers decrease eddy currents almost as much as having no cover at all, though some currents still manage to swirl around the whole perimeter of the open cover. If the cover were to have a very fine cut through it somewhere, there would be virtually no eddy currents to speak of.

Theoretically speaking, of course.

 

[thanaton]

Re: Questions about open humbucker cover.

Theoretically speaking, of course.

No, it's all true.

 

[beaubrummels]

Re: Questions about open humbucker cover.

No, it's all true.

Oooh, then please post the results of your experiments proving it.
Or is your science based on "alternative facts?"

 

[thanaton]

Re: Questions about open humbucker cover.

The principal of the design does not involve any particular implementation. You confuse the "principal" with an early prototype. In theory a HB with perfectly balanced coils will cancel out any external noise applied uniformly upon the coils. That's why some HBs are more quiet than others. (e.g. Blaze bridge vs Blaze neck)

Humbuckers don't cancel electrostatic fields, only electromagnetic fields. Electrostatic interference is where your guitar is one half of a capacitor, and the source of the electrostatic interference is the other side of the capacitor. There's no magnetic polarity to cancel, there's only this side over here, and that side over there. The fact that you don't hear a whole lot of additional noise by uncovering a humbucker or forgoing cavity shielding just does to show that electrostatic interference isn't as big of a problem as electromagnetic interference. Electrostatic interference is stronger the higher the frequency, but the higher frequency interference can rectify into audible, low frequency noise inside the guitar amp.

 

[thanaton]

Re: Questions about open humbucker cover.

Oooh, then please post the results of your experiments proving it.
Or is your science based on "alternative facts?"

Prove what? What exactly do you take issue with?

 

[AlexR]

Re: Questions about open humbucker cover.

Everything you're saying. Now the shoe is on the other foot we need proof of everything you are saying.

 

[thanaton]

Re: Questions about open humbucker cover.

I've cited the principles of physics that underpin what I'm stating. If there's something you disagree with, read up on the subject in question, and give a reason why you disagree.

 

[AlexR]

Re: Questions about open humbucker cover.

And yet we say these sort of things to you and you object.
We offer graphs in some cases and you ignore.

Its about time you started to be able to learn from others on this forum who have vastly superior knowledge about pickups....assuming this is a skill you can do.

 

[thanaton]

Re: Questions about open humbucker cover.

I'm still not certain what I've stated that you disagree with ... specifically.

 

[AlexR]

Re: Questions about open humbucker cover.

Give us proof.....simple really. We don't believe you know what you're talking about until you offer proof.

 

[thanaton]

Re: Questions about open humbucker cover.

That's very much not specific.

 

[Obsessive Compulsive]

Re: Questions about open humbucker cover.

If Thanaton's arguments are based on theories already scientifically proven by somebody else, and already accepted by the scientific community, universities, etc,. does he need to offer proof? It's like demanding proof for E=mc2.

 

[AlexR]

Re: Questions about open humbucker cover.

That's very much not specific.

Specifics were already taken care of right from the start. You're avoiding the issue.

 

[AlexR]

Re: Questions about open humbucker cover.

If Thanaton's arguments are based on theories already scientifically proven by somebody else, and already accepted by the scientific community, universities, etc,. does he need to offer proof? It's like demanding proof for E=mc2.

Most of what he asks for proof for is also covered by your scenario.

It is nothing more than a crude and childish exit clause he is seeking in the many times when he has used it. It is getting tiring....

 

[thanaton]

Re: Questions about open humbucker cover.

Eddy currents swirl perpendicular to the changing magnetic field.

That's just a fact.

The string is magnetized in the same direction as the pole piece, so the eddy currents move around in circle patterns directly below the guitar strings.

That's how it be.

The currents swirl in the slugs and screws, and if you have a metal cover, then they also swirl in the cover, over the slugs, and around the tops of the fillister screws.

That's how it works.

The open top covers decrease eddy currents almost as much as having no cover at all, though some currents still manage to swirl around the whole perimeter of the open cover.

Unfortunately this is true.

If the cover were to have a very fine cut through it somewhere, there would be virtually no eddy currents to speak of.

No circular continuity = no eddy current. Pretty neat huh?

 

[greekdude]

Re: Questions about open humbucker cover.

Humbuckers don't cancel electrostatic fields, only electromagnetic fields. Electrostatic interference is where your guitar is one half of a capacitor, and the source of the electrostatic interference is the other side of the capacitor. There's no magnetic polarity to cancel, there's only this side over here, and that side over there. The fact that you don't hear a whole lot of additional noise by uncovering a humbucker or forgoing cavity shielding just does to show that electrostatic interference isn't as big of a problem as electromagnetic interference. Electrostatic interference is stronger the higher the frequency, but the higher frequency interference can rectify into audible, low frequency noise inside the guitar amp.

Thanx for the info. Also with faraday cage shielding one can protect ONLY against high freq/radio frequencies. Against low freq EMI (which is the basic problem for guitar pups), the faraday cage principal does not help.

 

[RogerMexiko]

Re: Questions about open humbucker cover.

I've cited the principles of physics that underpin what I'm stating. If there's something you disagree with, read up on the subject in question, and give a reason why you disagree.

Yes, the physics you site cannot be argued if you got lucky and sited them correctly. Unfortunately the physics does not address materiality. Does what you describe enter the realm of perception? Everyone has stated that they can hear no difference. If your arguement(s) are to be relevant here you must demonstrate how the physics principle are in the domain of perception not just underlying DoDas.

 

[GuitarDoc]

Re: Questions about open humbucker cover.

Eddy currents swirl perpendicular to the changing magnetic field. The string is magnetized in the same direction as the pole piece, so the eddy currents move around in circle patterns directly below the guitar strings. The currents swirl in the slugs and screws, and if you have a metal cover, then they also swirl in the cover, over the slugs, and around the tops of the fillister screws. The open top covers decrease eddy currents almost as much as having no cover at all, though some currents still manage to swirl around the whole perimeter of the open cover. If the cover were to have a very fine cut through it somewhere, there would be virtually no eddy currents to speak of.

You realize, of course, that the OP was asking if there was a "sound" difference not a theoretical difference explained by physics?!

While we appreciate your knowledge of physics, it's nice to be tuned to practicality and to the OP's question.

 

[GuitarDoc]

Re: Questions about open humbucker cover.

Eddy currents swirl perpendicular to the changing magnetic field.

That's just a fact.

The string is magnetized in the same direction as the pole piece, so the eddy currents move around in circle patterns directly below the guitar strings.

That's how it be.

The currents swirl in the slugs and screws, and if you have a metal cover, then they also swirl in the cover, over the slugs, and around the tops of the fillister screws.

That's how it works.

The open top covers decrease eddy currents almost as much as having no cover at all, though some currents still manage to swirl around the whole perimeter of the open cover.

Unfortunately this is true.

If the cover were to have a very fine cut through it somewhere, there would be virtually no eddy currents to speak of.

No circular continuity = no eddy current. Pretty neat huh?

So then you are confirming what everyone is saying...that there is no perceptible sound difference with open covers as opposed to no covers.
Then why are you being so dogmatic and argumentative?!
Drop your pride and just say..."yes I agree, and physics proves that there is no audible difference".
Period.
End of story.

And as an added benefit, you don't rile and upset/stress all of the other good members of this forum.