Noiseless Dimebucker, why and how?

[capibat]

Hello all,
I recently got a guitar with a Dimebucker in it and noticed that this humbucker is absolutely noise free compared to any other Seymour Duncan I've tried which are not many but still: 59, jazz, distortion, black winter set, JB, custom5, custom custom.

It's not that the other guitars are poorly wired, they are pretty quiet actually as I've redone all my wiring with good wires and fresh new electronics, but compared to the Dimebucker and the B&B XL500 I have all the other SD have a small hum (60Hz) and static which is normal under high gain applications. (Also I'm only talking about when the guitar's volume is at max and it's not being played)

I assume this has to do with the original XL500 design though I would like to know why this this real noiseless feature isn't used in other humbuckers?

I hope anyone with better/deeper understanding on humbucker designs can comment on this.

Thanks!

 

[uOpt]

Re: Noiseless Dimebucker, why and how?

In a PAF style humbucker with no cover there is a small source of noise, and that is between the pickup lead entering the baseplate and then going 4 individual access wires to the 4 coil ends. That has humbucking in place due to the reversed coil polarity, however that would only work if the wires were all oriented the same way and no partially shielded by other conductive junk around them such as the coils.

This hole is plugged by a humbucker cover, but a grounded ring of conductive metal around the coils, enclosing the access wire, will also help.

Also, you might by coincidence have gotten a pair that has a particularly even wind between the two coils.

 

[idsnowdog]

Re: Noiseless Dimebucker, why and how?

It might have a rfi shield around the coils? It also may have inherited some of the Bill Lawrence design elements. Every BL design I have used has been very low noise.

 

[capibat]

Re: Noiseless Dimebucker, why and how?

So if I understand this correctly, the ring or (housing in this case) around the coils in the Dimebucker / L500 design is what makes them absolutely noiseless?
If so, could this be implemented on other humbuckers without changing their tone?

 

[EDX]

Re: Noiseless Dimebucker, why and how?

IIRC it has more to do with the fact that the dimebucker has copper foil as internal shielding and its narrow magnetic window due to the rail polepieces design

 

[uOpt]

Re: Noiseless Dimebucker, why and how?

So if I understand this correctly, the ring or (housing in this case) around the coils in the Dimebucker / L500 design is what makes them absolutely noiseless?
If so, could this be implemented on other humbuckers without changing their tone?

I wouldn't say absolutely.

But yes if you take an uncovered humbucker and put grounded conductor foil around the bit of unshielded access wire you will reduce noise. Of course a cover would do the trick, too.

As I said before, if you have one that is really now on noise the difference to other pickups will also be that you got by coincidence particularly even coils.

 

[capibat]

Re: Noiseless Dimebucker, why and how?

Thanks for the replies.
Digging through the forum I found a thread about a magnet swap in the Dimebucker and there was a picture of one that was taken apart showing the foil under the coils.
I understand that using a metal cover changes the tone of the humbucker getting rid of some highs so I think I will get some of this copper foil and try this method on the other humbuckers

About having particularly even coils, I also understand the logic about this and I find it interesting that the XL500 I have (4) are all as low noise (or absolutely noiseless) as the Dimebucker I'm describing here, hence my question about this noise-free characteristic. If having even coils is one of the must-have components of the noise-free feature I find it fascinating that all the XL500 are absolutely within spec. This noise-free I'm talking about is as if you had turned down the guitar's volume all the way down.

I'll report back when I get the chance to try the copper foil tape technique.
Thanks again for your help!

 

[Gibson 1964]

Re: Noiseless Dimebucker, why and how?

So if I understand this correctly, the ring or (housing in this case) around the coils in the Dimebucker / L500 design is what makes them absolutely noiseless?
If so, could this be implemented on other humbuckers without changing their tone?

It needs to be a metal. Some of the Wilde L500s have it and some don't. (It is a feature you have to pay a little extra for.) It does slightly change the tone according to Becky and Bill Lawrence. To quote Becky on the difference, the "highs are a bit sweeter." I have one set that has it and a couple that don't.

I also know Bill Lawrence wanted exactly consistent coils, (Conversation in his shop on open house day) so my guess is that the dimebucker would have balanced coils.

 

[EDX]

Re: Noiseless Dimebucker, why and how?

actually a good way is made something similar to what gibson does with some of their humbuckers, putting copper foil around the coils and the insulations of the access wires, then the cloth tape, also you could shield the pickup cavities

it also could be that the guitar is very well shielded

 

[uOpt]

Re: Noiseless Dimebucker, why and how?

Foil inside the coils has no shielding function. It is just a sink for eddy currents changing the sound slightly.

 

[EDX]

Re: Noiseless Dimebucker, why and how?

not inside, but surrounding the coils and the access wires like on this one

 

[uOpt]

Re: Noiseless Dimebucker, why and how?

If you shield the access wires noise goes down

 

[DrNewcenstein]

Re: Noiseless Dimebucker, why and how?

Then again, the Dime could be bad :lol:

 

[idsnowdog]

Re: Noiseless Dimebucker, why and how?

not inside, but surrounding the coils and the access wires like on this one

That's called a RFI shield and it is grounded so the noise doesn't enter the coil and end up getting amplified. The scientific term used for it would be a Faraday Cage. In this case the pickup isn't completely shielded since the top of the pickup is still exposed without a cover.

 

[capibat]

Re: Noiseless Dimebucker, why and how?

it also could be that the guitar is very well shielded

I don't think it's any guitar in particular as the XL500 will perform the same way regardless of what guitar they are in. And actually, when I swapped the L500 set for a SD Distortion/59 the usual noise floor comes back.

That's called a RFI shield and it is grounded so the noise doesn't enter the coil and end up getting amplified. The scientific term used for it would be a Faraday Cage. In this case the pickup isn't completely shielded since the top of the pickup is still exposed without a cover.

Thanks for this, I didn't remember the name of it but I was thinking the housing of this design works as a Faraday Cage. There is a version of the L500 that is not shielded and I can see that the interior of the housing is not covered with copper foil (that is the only XL500 I have that isn't shielded and sort of has a similar noise floor than other pickups).
About the cover, since this design in particular has no cover but is completely noise-free, what would a metal cover add in terms of performance then?

 

[uOpt]

Re: Noiseless Dimebucker, why and how?

It gets a little confusing here. The two coils are bucking each other's hum. They don't need a shield. And even if you wanted to, the shield only helps against the noise from oscillating electrostatic fields, not the magnetic ones. The humbucking works against both.

The small bit of access wire, however, benefits from a shield. Under high gain it can get noticeable EF interference (magnetic isn't a big factor given the wire length exposed).

 

[capibat]

Re: Noiseless Dimebucker, why and how?

uOpt:
What would be the bit of access wire that benefits from a shield in this case?

 

[uOpt]

Re: Noiseless Dimebucker, why and how?

Not in that picture, the exposed wires are on the other side of the baseplate where the wire shield ends and before it goes into the coils (under the tape).

Of course that assumes the end of the wire is in a shielded cavity.

 

[capibat]

Re: Noiseless Dimebucker, why and how?

Oh I see. I would have to unwrap the tape to gain access to that part of the wide.
So, getting rid off the noise completely like the Dimebucker design does would require both a sealed cavity and the shielding of the (little) exposed wire.
I guess that is the purpose of the housing in this design and I would have to shield the pickup cavity in order to get a similar result.

If this is so, why isn't this method used in all humbucking (the housing I mean)? Or am I missing something in the equation?
I doubt SD knows this already and just doesn't want to use this method, perhaps this housing changes the sound of a humbucker too much and it's not desirable?

 

[uOpt]

Re: Noiseless Dimebucker, why and how?

Oh I see. I would have to unwrap the tape to gain access to that part of the wide.
So, getting rid off the noise completely like the Dimebucker design does would require both a sealed cavity and the shielding of the (little) exposed wire.
I guess that is the purpose of the housing in this design and I would have to shield the pickup cavity in order to get a similar result.

If this is so, why isn't this method used in all humbucking (the housing I mean)? Or am I missing something in the equation?
I doubt SD knows this already and just doesn't want to use this method, perhaps this housing changes the sound of a humbucker too much and it's not desirable?

The way the humbucker was designed it was shielded in that area, with the cover. Removing the cover exposes the wire, but if you don't use a lot of gain it isn't bad. Also, almost everybody lacks shielding and uses their belly as a shield for the electronics cavity so the little bit of exposed wire is the least of the problems.

I can only repeat what I told you several times, and what you ignored several times. Your particular dimebucker or the particular guitar it is in is unusually quiet. Just for starters you need to randomly get particularly even coils, and the dimebucker isn't any better at that.

It's not the "Dimebucker design" that is completely hum-free. A dimebucker with an unshielded cavity will hum and buzz like everybody else. Yes, it has a "partial cover" and doesn't expose that little bit of wire. But a covered PAF with both coils very even is every bit as good.