HB pickup polepieces

seany65

The polepieces on the pickups (HV58's) I've got are not threaded and are unadjustable because they are 'just for aesthetics', according to customer services of Entwilstle.

This has got me thinking, Is this a cost-cutting measure done on all cheap pickups such as 'axesRus' (used to be?), or are they taking advantage of the 'fact' that most HB pickups are supplied with a 'flat' setting on the polepieces and this is hardly ever changed by the player?

I know single coils often/usually have slugs at different heights, but I've never noticed this on HB's. Would there be much difference if HB's did have poles of different heights?

Edit: changed all references fron "PUP's" to "pickups",  just 'cos I've read some members are a bit too sensitive to such things.

Bah! You lot just can't let me be a lazy turd, can you?

Dave_Mc

Not sure. Hopefully ash will see this and answer. I guess on some pickups it might be costcutting (the very cheapest entwistle, IIRC, only has slugs), but I think i've also seen slugs used for tonal reasons too on dearer pickups. Could be wrong.

How do you like the HV58s?

Adam_MD

I've noticed a difference when I've mucked about with polepieces not a lot though. All of my humbuckers have flat polepieces except for one which just sounds better after I mucked about with the heights.

OilCityPickups

Took a look at the Entwhistle web site ... and it says this about the HV58

'The classic late '50s humbucker, made to original vintage specs; Alnico V magnetic, enamel coated winding wire, scatterwound coils, plus the advantage of hard nickel pole pieces that deliver 10% more output without affecting the tone.' 

This is rather odd ... as original vintage specs certainly didn't include fixed pole screws! The other odd thing is that 'hard nickel' can't be used for pole screws ... as it's not magnetic!!! You'd not get any sound from your screw coil! Nickel plated yes ... we all use those ... but that doesent give you 10% more output!!

Part of the way you can get the best out of a PAF style design is by exaggerating coil imbalance ... by raising your screw coil screws (I always set them close to the fingerboard radius (take a look if you have Oil City or ASL fitted). It makes less difference with higher output pickups, and I often set those nearly flat.

GuitarMonkey

Nickel is ferromagnetic
http://en.m.wikipedia.org/wiki/Nickel

OilCityPickups

Not ferro magetic enough to make a pole piece with. Alloyed with other metals yes ... particularly aluminium and cobalt ... AlNiCo

It would make sense having nickel alloy poles with no threads if the poles were a nickel alloy like alnico, it's too hard to have threads cut in it ... . Doesent make for a pickup 'made to original specs' mind.

seany65

Thanks for the replies.

@Dave_Mc, I like them. I've really only played them 'clean', and they sound quite musical.

@TheGuitarWeasel, I got a little confused for a moment, then I remembered they have different versions of the HV58. I've got the covered alnico 2's. Doesn't mention polepieces, but they do say "...Alnico 2 magnetics..." and "...Alnico 2 bar...". I suppose they could mean polepieces by the former.

So some HB's do have polepieces at different heights? I've never noticed. How does this change the sound? I'd always thought single-coils had slugs of different heights to compensate for the uneven volume of the strings.

Would there be any real benefit having the holes tapped so they can take threaded polepieces, are there different types of polepieces available or would the time, effort and expense make it pointless?

OilCityPickups

seany65 said:

Thanks for the replies.

@Dave_Mc, I like them. I've really only played them 'clean', and they sound quite musical.

@TheGuitarWeasel, I got a little confused for a moment, then I remembered they have different versions of the HV58. I've got the covered alnico 2's. Doesn't mention polepieces, but they do say "...Alnico 2 magnetics..." and "...Alnico 2 bar...". I suppose they could mean polepieces by the former.

So some HB's do have polepieces at different heights? I've never noticed. How does this change the sound? I'd always thought single-coils had slugs of different heights to compensate for the uneven volume of the strings.

Would there be any real benefit having the holes tapped so they can take threaded polepieces, are there different types of polepieces available or would the time, effort and expense make it pointless?

No point in getting the holes tapped if it sounds okay, just enjoy it.

seany65

@TheGuitarWeasel, Don't worry, not even I'd do that.*







* Probably. ">

FelineGuitars

The original PAF that Seth Lover designed didn't have adjustable polepieces back in 1955. 

It was the fact that the marketing and sales guys wanted something to sell and that Gretsch had a double row of adjustable poles on theirs that made the design change so they had a feature to tell the shop owners about.

However as Ash says - raising the poles on one side unbalances the humbucker and gives more character - adds a wee bit of single coil-ish-ness

seany65

Thanks for the info, FelineGuitars.

Dave_Mc

seany65 said:

@Dave_Mc, I like them. I've really only played them 'clean', and they sound quite musical.

Thanks

seany65

How would otherwise identical 'buckers with 2 rows of adjustable polepieces differ in sound to ones like mine, basically without polepieces?

If the poles are at their 'normal' height would they sound different to mine?

Am I right in thinking that if 1 row is raised and the other row is lowered, they'd sound a little more like single coils than just raising 1 row?

OilCityPickups

seany65 said: How would otherwise identical 'buckers with 2 rows of adjustable polepieces differ in sound to ones like mine, basically without polepieces?

If the poles are at their 'normal' height would they sound different to mine?

Am I right in thinking that if 1 row is raised and the other row is lowered, they'd sound a little more like single coils than just raising 1 row?

Any change to pole piece length and mass changes tone ... not sometimes by a whole pile ... but enough that if you A/B them you might hear the difference. Two screw pole coils will have a fraction less output ... as there is less ferrous mass to transfer the field up to thee strings. Shortening the pole screws emphasises treble frequencies as well. One set of poles raised and one lowered makes the pickup fractionally less efficient at hum cancelling ... but the disparity of output would indeed make the pickup sound more single coil like.

seany65

Thanks TheGuitarWeasel.

Hmmm,

"Two screw pole coils will have a fraction less output ... as there is less ferrous mass to transfer the field up to thee strings."

I take it you mean that the magnet has less mass, as 6 extra holes have been drilled into it?

OilCityPickups

No, the ends of the screws never physically touch the magnet ... they seat in the steel 'keeper bars' that in turn contact the magnet. the field is then transferred up the poles to the strings. 

A twin screw coil pickups has two keeper bars ... what they call a metal spacer in this diagram

imalrightjack

seany65 said:

Edit: changed all references fron "PUP's" to "pickups",  just 'cos I've read some members are a bit too sensitive to such things.

Bah! You lot just can't let me be a lazy turd, can you?

@ICBM

OilCityPickups

seany65

@TheGuitarWeasel, those little doggies are actually Pups, not PUPs.

I have thought about going to one of the many "NGD guitar" threads and posting "Phwoar, look at the PUPpies on that" just to see if I can annoy certain members. )

(Edit : I've just been and gone and done it. "> )

Thanks for the diagram. Interesting. Seems odd to me that a 6-pole pickup that has 1 plastic shim and 1 metal shim would have a slightly higher output than a 12-pole pickup with 2 metal/steel shims.

@imalrightjack, ICBM isn't alone in being a bit miffed with PUPs, though. I suppose it's easy to get like that with a particular thing. I get annoyed with the adverts for new TV dramas that they show incessantly, including in the last ad break just before the new drama is shown. They did it with 'Vera' on Sunday.

OilCityPickups

The slugs are directly in contact with the magnet at their bases ... and have more mass. The plastic shim ... sits on the outside of the slugs (and is wood in many pickups) and is simply to rest the other side of the bobbin on ... so when you screw everything together the bobbins sit level.

seany65

@ TheGuitarWeasel, So the bobbin with the poles sits on the steel shim, and the bobbin with the slugs sits on the magnet, but neither does this completely and have to partly rest on the shims.

Thanks.

I take it there's good reasons why the magnet isn't wide enough to rest the bobbins on completely, such as cost or it would alter the sound etc.?