These are what you’d probably call “Standard” humbuckers covers, in that they have 6 holes down one side to accommodate the pole screws that are poking up through the top and I think it’s safe to say it’s the look we think of when we talk about covered humbuckers. That Honey burst Gibson® Les Paul®, immaculately polished, all the chrome** hardware sparkling under the lights, and as a final touch of class, covered humbuckers! Beautiful!
Now, in reality, Humbuckers are a little more than being just cosmetic additions, so for the sake of honesty, we’ll break this write up down into a few parts so its simpler, and you can cherry pick the information you need from this.
I’ve written a “potted history” of Humbucker pole spacings before today, so I’ll spare you the worst of it here, because it’s not really relevant to humbucker covers by themselves, and I’ll keep this to bare bones.
Rule of Thumb
“Officially” humbuckers come in 4 sizes (falling at the first hurdle, considering this product has 6 pole options on it!), and these can be divided into “Metric” and “Imperial” dimensions. That’s a complete lie, because there isn’t a great deal of logic applied to them either way that make them inherently metric or Imperial, so, frankly, your pretty safe in thinking of that distinction more as “What Gibson® did” and “What everyone else did”
Either way, it runs as follows.
The “metric” sizes are 50mm and 52mm – anything far eastern is usually these sizes.
The “Imperial” sizes run at 49.2mm and 52.5mm – slightly trickier because its not limited to USA produced pickups any more, but generally, higher end pickups will use imperial dimensions.
What size do I need?
Measuring your pole spacing, is easy. Don’t trust what a manufacturer tells you, don’t trust my guide below, please, measure your own pickups. Manufacturers do vary their production for various reasons, and no one is keeping track of this as closely as you’d hope!
So – to measure – get your pickup, and measure centre to centre on the pole SLUGS (Not the screws) High E to low E– they’ll have concentric rings printed into them, and you’ll be able to accurately line up a ruler with the centres.
Once you’ve got a measurement, double check it against the pole SCREWS, and you’ll have your spacing.
Check all pickups on the guitar, because its not uncommon to find a neck pickups with a narrower pole spacing then bridge pickups.
Who uses what size?
So as a very rough guide, here goes! A few brands we know about, and what fits what!
DiMarzio®* Standard 48.6mm, F Spacing €“ 51.05mm
Gibson®** Historic - 49.2mm, Modern 52.5mm Bridge, 49.2mm Neck
Seymour Duncan® Standard - 49.2mm, Trembucker® 52.5mm****
Artec Sounds - Neck 50mm, Bridge 52mm
G&B - Neck 50mm, Bridge 52mm
Rosewell Pickups® - Neck 50mm, Bridge 52mm
Ibanez ® - Neck 50mm, Bridge 52mm (Excluding models fitted with US made DiMarzio® Humbuckers)
Fender®*** Annoyingly, 49.2mm, 50mm, 52mm and 52.5mm…
Wilkinson® - Neck 50mm, Bridge 52mm
Axesrus® - we do things a bit weird because we don’t work to neck/bridge as a set size, but, generally speaking, we’re working in either 49.2mm, 50mm and 52.5mm.
*DiMarzio use a proprietary spacing system, no one knows why they came up with it to be honest. They probably started making replacement humbuckers before the Gibson standard (49.2mm) was widely known.
**Gibson, despite being the grand daddies of this stuff, can be a bit of a nightmare. They often state their humbuckers as being “50mm” spacing, they are not. They are simply rounding up. They also, occasionally, fit humbuckers to guitars in spacings that model shouldn’t exist in (I’ve seen a few guitars with 57+ and burst buckers that were 52.5mm before today)
***Fender will drive you to despair, because, lets be honest – they’re making guitars all over the world at this point. Some models will come with far eastern humbuckers, some will come with USA wound, some will even come with Dimarzios as standard. They can use any spacing!
****Trembuckers ®, Seymour Duncans brand name for a 52.5mm spaced humbucker, are a bit strange. They’re stated dimensions, are larger on the external (70mm length) then the internal of a humbucker cover – I’ve measured a Trembucker, and can confirm that the bobbins are only 68mm “long” and it DID fit into a 52.5mm spaced cover without issue, BUT, I’d advise caution. There is the potential that the coils would overlap the bobbin edges, and foul the cover. I can only speak of what I’ve seen, and it did work… however, by the letter of the law? Let’s take SDs spec sheet at face value – Trembuckers DO NOT FIT into humbucker covers. They require specific Trembucker® covers, available only from Seymour Duncan stockists.
If you tolerate this.
You’ve probably noticed that theres a (+/-0.5mm) in the drop down options for the pole spacing – this is “the tolerance” and frankly, it’s a wonderful thing as far as we’re concerned.
Basically, your pole spacing on your pickup, have a little wiggle room when it comes to their actual spacing in relation to the cover (and the base) – pole screws have a little wobble in their threaded holes, covers aren’t drilled micron perfect, and pole screws aren’t all exactly 3/16” heads.
So, in short – you’ve got about 0.5mm of play in there, which means you can fit a 52mm cover onto a 52.5mm set of bobbins, or a 50mm cover onto a 49.5mm bobbin (should such a thing exist!)
Its only really helpful with 52 vs. 52.5mm to be honest (and 52.5mm only really exists to account for some weird manufacturers who have come up with 52.8 and 53mm bobbins!)
So don’t sweat it too much. 52mm and 52.5mm, atleast from a covers point of view, are the same thing.
I dont think gtting covers to humbuckers is that difficult if i'm being honest, but, i suppose, i do build the things from scratch, so, maybe I'm a little blind to it, so, heres a quick "how to" on the topic.
In short, because the cover is metallic (so is conductive) is needs to be grounded (as do all metal parts on the guitar) - and the easiest way to do that, is to solder the cover to the humbuckers base (which is already connected to a wire which is destined to connect to the ground loop)
The cover also needs to be secured in place, so this process, kills two birds with one stone.
Now, "soldering" is a bit of a misnomer, because its not really soldering at all - its more a braze joint, or a weld... but your doing it wirh a soldering iron (most of the time!) so, lets just stick with calling it soldering for simplicities sake.
Prepping the humbucker
Everyone gets this wrong to start with. You want to get your humbucker, and back out ALL of the pole screws - this gives you a little more wiggle room, and gaining full benefit from the tolerences on the cover.
And, importantly, you want to remove any tape that is wrapped around BOTH bobbins. This doesn't mean the tape that is wrapped around each bobbin individually, but there should be a layer of tape that goes all the way around the pickup. Remove this to avoid it interfering with the later steps.
Expose the covers base material
This is important - you want to sand/scrape/grind/file through the covers plating layer (and the copper layer if present) to expose the base material (either German Silver or Brass) in the place where you want to solder to.
In short, whilst its not impossible to solder to an electroplated layer, its not easy, and will require excessive heat, which will, in most cases, cause the plating to fail. Its not worth the hastle frankly. a few seconds wotk with a mini grinder, or a few minutes with a file, and your all ready to go.
Personally, i like 2 solder joints to hold
the cover in situ, placed roughly between the D and G poles - but, honeslty? Theres no hard and fast rule. You could run a full seam if you like, but one either side is probably your best bet in terms of security.
Get the cover on there! Get the pole screw heads through the holes (you might have to back them out a little further, especially with 12 screw humbuckers!) and make sure everything is flat, square, and as you expect it to be.
Get your soldering iron on, as hot as you can, and your ready to do!
Dont forget protection!
Nice soft cloth, on a flat surface, flip the humbucker over, and you'll see this from the back. 2 points of exposed base metal, sat up against the metal of the humbuckers base. The solder can bridge a bit of a gap, but if your more then about 5mm, you might want to go expose a little more on the cover.
You should be able to see here too if anything is out of square, or if you've pinched any of the plastc coated hookup wires, which you obiously want to avoid. If your happy with how it looks, then we....
Just like soldering anything else, get your hot iron onto the point where you want the joint (in this case, on both the base and the cover) and feed your solder onto the iron.
Hold it all for a second until you get a nice flow, remove the iron, and it'll set into a very strong, solid joint.
Repeat the process on the other side, and your done!
A word of warning - watch for the hookup wire coming out of the base. Its easy to forget about it and catch it with the "shaft" of the iron, and melt the thing.
Something like this
And thats it - the covers grounded, its secured, its neat and tidy, and your done!
Just needs the pole screws putting back down so they look nice, and your pretty much done.
Now, in my opinion - if your fitting a cover to a "new" humbucker (one thats not been wax potted before) - you'll want to wax pot it.
And if your fitting a cover to an "old" humbucker (that HAS been potted)... you'll want to repot it, and if your replacing a cover on an old humbucker, you're still going to want to wax pot it. (the only exception, is historic builds, where wax potting is intentionally ommited in an effory to be "period correct)
Essentially, the cover has the potential to introduce microphonic feedback into the circuit (its conductive, it can vibrate out of sync with the coils of the pickup) so we really, want to lock it in there nice and tight, and remove as much air from the thing as possible.
But, i would say that wouldn't i? If i'm fitting a cover to a humbucker, its being sold, the last thing i want is a pickup coming back for being microphonic, and, importantly, i have a wax bath running 24 hours a day... its no problem for me to pot a pickup.
I do, however, understand, that this isn't really an option for everyone else in the real world, and i know, for a fact, that most people fitting our covers to existing humbuckers, aren't wax potting them, and very few people are complaining about microphonic feedback.
So, real world? I'd always wax pot a pickup after fitting a cover, but, you might get away without it. Especially if your working with realtively low output pickups. I wouldn't suggest it personally, but, consider this fair warning.
How to wax pot?!
I'm afraid i'm going to have to chicken out here - i can tell you how to wax pot a pickup "properly", no problems what so ever!
You get a wax melter, you disolve a load of parrafin wax
(We like to add a little bees wax to lower its melting point!), run it at about 50c, get it liquid, submerge the pickup, leave it alone for about 30 minutes, take it out, and then clean it off.
Nice and easy, slightly messy and, importantly, very safe!
Sadly, i cant really tell you how to do it safely without a wax melter. The "pan on the hob" method, risks a fire, plain and simple, and i wouldn't suggest it what so ever - so, to tow the official line? If your serious about this? Go get a wax melter. They'll set you back £15-30, its safe, and you can do your eyebrows whilst your at it.
And thats about it - get it clean (degreased is a god send, but you might need a little heat from a hair dryer to shift any excess wax) and your done. Give it a test to make sure you've not damaged anything along the way, and all being well, its ready to go back in the guitar.
I think this is a little bit redundant to be honest, because the site has the "smart swatch" system, which shows you how everything looks once you've assembled it, and whilst its a bit "too perfect", it is pretty accurate to what your going to get. However, i will concede that sometimes, real pictures of real things, can be helpful, so, heres another photo dump, detailing as many of the colours as i can.
Now, i've detailed what covers do, what how they affect the sound of your pickup, and if you can live with that, its probably worth knowing what the things actually look like.
Nickel (importantly, WITH the copper underplate), is, essentially, a mirror finish - a slightly yellow/white tint to the "silver".
Similar to Nickel plating, but with a sligtly blue "tint" to the silver. Harder wearing then any other colour believe it or not, with better resistance to scratching and less reactive to sweat.
These are just the unfinished covers, no copper under plate, no electroplate, no polishing, as pure as they come! Just a shaped hunk of German silver, completely with tool marks from manufacture and scuffs from being handled and stored prior to us getting them. A nice little part to use as a "ready made" relic, but they can be polished up with a metal polish to a mirror shine. Without an electroplating, they age very quickly, so aftera year or two of serious playing, expect to see that zebra stripe pattern where you've hit the cover with your pick, but never under the strings.
It is what it is really. A fairly low karat gold is usually the case when it comes to plating (at least outside of jewellery) interestingly, the variation between different parts in gold comes down to the karat of gold used in the plating, the darker, more orange gold colours come from higher quality gold. Ours are fairly middle of the road "guitar part gold" to be honest. Worth nothing that whilst gold normally wont tarnish, it will get dirty, and cleaning gold plate is the very devil, because its soft and thin (we've all seem gold humbuckers where the platings rubbed off? That's why! Its not that its cheap gold, or "not gold" (granted, its low karat usually)) it's possible to just rub straight through most gold plate with a bit of force and abrasion. So go for gold (all gold, not just our humbuckers covers but anything gold plated!) with caution, itlooks great, butiIf its getting used and abused every day, it's going to show its age.
NO COPPER Nickel Cover
Whilst "No copper" covers, tonally, sound the best - you can probably see from this photo why, cosmetically, we copper underplate! All of the "grain" of the nickel is peeking through that final electroplate layer, and making it look a little bit rustic.
Black is Black, it's commonly thought to be powder coating or painted, but it is actually Electroplating (in a fashion anyway), and as such, offers all the benefits/drawbacks there within. It's actually a process that causes oxidisation of the base material (that copper layer) which is then converted into Cupric Oxide. Its not exactly common with humbuckers covers, but it looks fantastic as long as you keep it clean!
I should have, honestly, written this about 9 years ago when we first stocking cosmo parts, but, better late then never.
Probably best described as "Gun metal" Chrome, and isn't a million miles away from "blued steel" (which is what gun metal usually is!), almost a half way house between Chrome and Black really. Not as hardwearing as Chrome, but way more then black. It turns up fairly often in Ibanez guitars, and is sometimes called Ruthenium, Black Nickel, or Black Chrome... all of which are fairly confusing.
Nice colour all in all, slightly limiting to match other hardware to, but Gotoh do pretty much all their parts in Cosmo too.
Honestly, not my favourite finish for a cover... but maybe, because i dont like the name "relic" we informally use. It doesn't look like a relic from a bygone era, it doesn't look like its a cover thats 70 years old thats been loving cared for, but is showing its age. It looks fake. It looks artificial.
I suppose its not without its charms though, whilst it wouldn't be my first choice to stick on a classic guitar to mimic natural aging, its got a bit of a feel to it hasn't it? Like acid wash denim or pre-ripped jeans.
Similar to Distressed Silver i suppose - but slightly more acceptable from where i'm sitting. It still looks false (even to the point where old copper doesn't look anything like this) - but, its actually pretty cool to me. Certainly not for everyone, but, might just be the thing your looking for.
I'll go into a little more detail on some of the finer detail about some of the topics i've covered above.
Raw out of the box
When I say "it’s as it comes from the factory", I can’t stress that enough - it’s a pickup cover that’s been plucked out of a parts bin before it should have gone off to electroplating. It’s not been polished, it’s not been tumbled, it’s not been smoothed, its not been handled with kid gloves… it’s a hunk of German silver. It looks like what it is. Scratches, scuffs, marks, grease, burn marks, small dents and burrs are all to be expected.
I think this photo of a raw cover is a little more “warts and all”, and shows what I mean. Its pretty rustic. Its not my favourite “finish” in the world… but, tonally? As I’ve mentioned in the “Cover and Base” write up? It’s the purest you’re going to get.
AND, whilst I’ll concede that it’s a bit rough and ready straight out of the envelope, because its just a hunk of metal? Theres nothing stopping you going wild with it.
Raw with a bit of age
And here’s where raw gets interesting for me – because its not electroplated, its essentially, open to the elements. Its going to be hit by a pick, rubbed at, bled one, soaked in sweat, scratted at with the hem of your T-shirt, and over a year or two (assuming you actually play the guitar!), very organically, its going to get polished into quite an interesting pattern.
What I’ve called “zebra striping” earlier on in the write up (maybe Tiger stripe would be more fitting?) – the area between the strings has been polished by every day life, and the area under the strings has been left relatively untouched. The pickup looks 30 years old, but, really, it was a Hot Iron our tame guitarist used to teach for about a year.
Its essentially, the reverse of what happened with the original humbuckers(the ones without the copper underplate) – the electroplated layer was thin and soft, it was polished away by daily life, and left those stripes, with the shiny section under the strings, and the raw section between them. So, not quite the same, but starting with raw, generally, ages up a lot faster then electroplating ages down.
Brass-o doesn't ruin tone-o!
Before I come across as the master craftsman here, I have to point out, I am NOT a polisher! The length and breadth of my experience pretty much starts and finishes with attacking my mother’s fireplace with a tin of Brasso as a kid, so, please, excuse my amateur attempt.
And saying that, starting with what I know? Raw covers tickled with a bit of liquid metal polish, start to look a lot more presentable. We’re not up to the immaculate mirror finish of an electroplated cover by any means, but by this point, I’m liking it a little more. It looks a little less “factory floor” at least, and certainly wouldn’t look out of place on a guitar with a bit of age, and, as you'd expect, theres a bit of shine there.
Raw after a "real" polish
Again, I CANT POLISH – but I’ve attacked this cover with the buffing wheel, and a bit of gentle compound, and its come up to a pretty good mirror if you ask me. I’ve not removed all of the surface marks, or worked through the grits or put any real effort in, but I did want to show that unplated covers can be brought up to mirror finish if that’s what your going for.
It’s a little pointless from my point of view, because its still raw German silver. Its going to oxidise pretty quickly, and it’s so soft that even if you did polish it to perfection, its going to scratch fairly easily (that said, theres nothing stopping you polishing out the scratches again, and, it is “tonally pure”) – not something I’d do personally, purely because nickel plating is available, but each to their own, and its not a million miles away from a “nickel plated” cover.
Dont mess about with Gold!
Gold gets a bit of a hard time with guitar parts, and I’ve mentioned above, that its not exactly 24 karat stuff, but, on the whole, its OK, its definitely gold (rather then some substitute yellow metal - the bode plots prove that because its so conductive), and gold being expensive, it’s probably expected that its not plated on incredibly thick!
The problem is, with the greatest respect here, your not looking at a £200 gold plated cover here… its, within the grand scheme of things, pretty cheap, so you/we are entirely at the mercy of the electroplaters. If gold (the raw material) starts to get more expensive, you’ve going to see the “depth of colour” of gold decrease, and visa versa (because the factories don’t want to be shipping out “barely yellow gold” any more then we want to be selling it!) – so, be aware, Gold changes as a colour. We try to keep on top of it, but I have VERY limited control over the gold markets… very limited indeed!
And all that aside – If it was 1 Karat gold or 24 Karat gold plate… its still gold. Its still an incredibly soft metal, plated very thinly… it will, in day to day life, rub through. The photo above is the side of a copperless Gold cover I’ve rubbed a few times with the brasso rag! Its that thin.
Gold over copper is a little hard wearing, and generally, gold over copper over brass (or zinc) has a slightly deeper shade to it, and gold over German silver is slightly lighter… but its always pretty soft, and will not take a polishing what so ever. So please, don’t even try.
Covers and Base Material
I think I’ve covered pole spacing pretty well under the “pole spacing” header, so, whilst bases and covers are impacted by that aspect of humbucker “design”, I’ll gloss over it in this section and concentrate a little more on the impact covers and bases actually have on the signal being produced by the coils.
Its one of those weird things with humbuckers, I wont say its overlooked as such, but its certainly not widely embraced as you’d think.
So, with humbuckers – you’ve usually got 2 options of material when it comes to covers and base plates, either Brass or German Silver (sometimes called Nickel Silver, or just Nickel) and its commonly believed that “brass is ‘bad’ because it sucks out top end” and “German Silver is ‘good’ because it doesn’t effect the tone” – and, broadly speaking, that’s actually correct! But, as with most things, its not as clear cut as we’d like as engineers, so, I’m going to try to drag this topic well and truly into the light!
Ace of Base
So lets start at the bottom, and deal with “base plate material” – Brass vs. Nickel!
Base #1 (Purple)
Base #2 (Blue)
We can see from the above, that, really? There isn’t a great deal of difference between the two options (I’ve included “no base” too, for completeness’ sake). If anything, a brass base plate, compared to German Silver, isn’t actually sucking out any top end, its sucking out a little of everything up to the resonant peak, but past that, its comparable to German silver – so we’d perceive that, not as “sucking out top end”, in fact, the complete opposite, we’d hear that as the pickup gaining a little definition, and likely, being a shade brighter! However, it’s a fairly small change in that regard, its certainly not as drastic as we’d be lead to believe in the old “Brass bad/Nickel good” argument.
And, we can see that both German Silver and Brass, and both having an effect on the signal compared to the “no base” version of the pickup (and this is telling, because the same happens on a Telecaster® bridge pickup, or a P90) – without a base, we’re actually retaining a little more of the signal above the resonant peak. Its an unrealistic dream to say “humbuckers without bases sound better”, simply because the mounting system for the pickups is pretty reliant on a metal base, but we can certainly see that the base material, whilst only a minimal change, is always losing “something”. They’re always going to cause a loss of something.
Real world, we’re probably going to “hear” a German silver base as being a little warmer, a little smoother, a little more forgiving (evident in the wider peak) and we’re going to “hear” a brass base as being a little brighter, a little more cutting, a little crisper.
So, with that in mind, it does beg the question – is brass as bad as we’ve all been led to believe?
Well? Probably not, at least from a tonal point of view – we’re not seeing any enormous impact on the signal, we’ve not seeing a huge change to the shape of the plot, frankly (with uncovered pickups!) Brass vs. German silver bases is little more then an extra option for “seasoning”, and I suppose, that’s to be expected, the base is on the bottom, it’s a long way away from the strings, and with all of this stuff, the bigger impacts are things that sit between the coils and strings, not beneath!
However, there are one huge point of note here.
Soldering to Brass!
Brass is an absolute pig to solder to! Its far more conductive than German Silver, so it wicks the heat away from the point you want to solder to, making it difficult to make a good, solid joint. This isn’t a massive issue when the only solder joint you need to make to the base is the ground wire for the hookup, but it can be a real pain if you’re fitting a cover, where you’re making a couple of small spot weld to hold the thing in place. German Silver, by comparison, is a poor(er) conductor, it doesn’t wick the heat as effectively, so soldering to it is much easier.
Frankly, when the humbucker was invented, chances are, German silver wasn’t chosen as the preferred material because it had some wonderful, musically adjacent alloy that left the humbucker sounding closer to the “ideal” – it was probably chosen because it was easier to solder to. It costs more to produce then brass, but, frankly, its quicker to work with, introduces less risk during pickup assembly (better to make your spot welds with a solder iron then with a small gas torch!) meaning less tools required, meaning less training, and less fire risk! (a weirdly big deal in guitar manufacturing!)
Bases – a conclusion
If you’re building an uncovered humbucker, and your happy soldering the ground connection onto the base, brass is as good as German silver! Its slightly cheaper, and it’s brightening the pickup ever so slightly. It’s probably so small a change that its below our comprehension, but at least you know now, what’s happening. You can lean into it if you want to, or don’t. Just be aware, brass isn’t bad! (And that’s likely going to be the last time I type that, because things are about to get interesting!)
I know this is purely a personal taste thing, but I don’t think they’ve ever invented anything that looks as good as a covered humbucker in a Gibson® (and I’m a Fender® man!) so I certainly won’t be using this section of the write up as a stick to beat anyone who feels the same way! Covered humbuckers are beautiful! However, they’re one of those things where, the “truth” about their impact on pickups has become lost along the way, so, just like bases, let’s see if I can bring a bit of perspective to the whole thing.
So, just like base plates, you’re dealing with 2 different materials when it comes to covers – either Brass or German silver again (the “no cover” option is at least viable here though, where with the base plate, its more of a hypothetical, and, technically speaking, Stainless steel covers did exist, but it was short lived, and I don’t believe it ever went past the prototype stage of the initial humbuckers!)
And, we’re back to the old trope! “Brass sucks out top end, German silver doesn’t affect the sound” – so lets get straight into the graphs.
Base #1 (Purple)
Cover #1 (Purple)
Base #2 (Blue)
Cover #1 (Blue)
Now, that graphs actually REALLY unfair, but, real world? Its true I’m afraid. If I go grab you a Classic 50s, slap a Chrome plated German Silver cover on it, that’s what’s going to happen to your signal. I think we’d all agree, that that is definitely “an affected sound” right?
Now, before we get into what’s going on with German Silver, lets agree too, that brass is doing EXACTLY what we thought it would do too. Its sucking out a huge amount of voltage from the resonant peak, and its making the pickup sound very woolly. We’d definitely perceive that as “top end has been sucked out”.
So, the weird thing here, is that German silver is actually sucking out a lot of top end too! Not as much as brass, but its still having a big impact! Now, the reason as to why, is quite interesting.
To explain this well, is going to get pretty boring, but, considering your entertaining the idea of winding a humbucker, presumably for fun, this might be right up your street, and its worth knowing, so bare with.
The ”problem” with humbucker covers, isn’t actually to do with their material per se. Its more to do with the conductivity of the things, and, as I said earlier – when something is placed between the coils and the string? That’s when we see a big impact.
So the above graph, is a Chrome plates cover in both instances right? The thing with electroplating, is that, primarily, it’s a cosmetic thing, its got to look great hasn’t it? And the way you get an absolutely immaculate finish on your electroplating, is to first, plate the part in copper.
That gives the plating material (be it Chrome or Nickel or Ruthenium or Gold) a better “bed” to adhere, so its less likely to show the “grain” of the Brass/German silver, and its less likely to fail in the short to medium term. Copper “underplating” is most definitely “the norm” when it comes to humbucker covers (and most electroplating) because it gives the best possible finish.
However – copper, is also, VERY conductive! (Way more than brass or German Silver!) so what we’re actually seeing with the above graph, whilst real world (you buy a chrome cover? Its got a copper underplating!) – its not really a true reflection of Brass vs. German Silver – its Brass + Copper + Chrome vs. German Silver + Copper + Chrome!
THIS, is a true representation of Brass vs. German Silver (vs. Brass + Copper+ Plating vs. German Silver+ Copper + Plating vs. Nothing)! A pickup fitted with a completely unplated covers! Just the bare alloy! (its actually a Telecaster® neck pickup, simply because we don’t carry humbucker covers in raw brass – no ones ever asked for them to date!)
White - Uncovered - 27.6dBV@7.13kHz
Red - German Silver w/No Copper Unplate - 23dBV@7.13kHz
Pink - German Silver w/ Copper Underplate - 16.4dBv @ 7.37kHz
Blue - Brass w/No Copper Underplate - 13.7dBv@7.54kHz
Green - Brass w/Copper Underplate - 9.8dBv @ 7.81kHz
And we see something very interesting! Raw German Silver actually isn’t as bad as we think, is it? We’re still losing a fair bit of voltage at the peak, but no where near as much as we are with a copper underplate.
And we can see that in a slightly more “real” test with a humbucker, comparing a copper Chrome plated/coppered German Silver cover to a Chrome plated cover WITHOUT a copper under plate!
Blue - Uncovered - 24.5dBV@7.63kHz
Green - German Silver w/No Copper Unplate - 21.3dBV@7.21kHz
Purple - German Silver w/ Copper Underplate - 18.7dBv @ 7.21kHz
So that does give some credibility to the “brass bad/German Silver good” argument. I still can’t sit here and say “German Silver doesn’t affect the pickup”, but we can say that, if German silver covers aren’t plated/aren’t copper underplated, they have the least effect, the copper underplate has an impact, and brass is having a huge impact. Covers affect pickups. Its as simple as that. If you’ve got a humbucker you adore that’s currently uncovered? Chances are fitting a cover, regardless of material, is going to change it considerably.
Now, to round this out before we get into the next part, it may seem that I’ve not covered all the angles here. I promise you; I have! I’ve just had to trim this down so it doesn’t turn into a dissertation – so, quick and dirty? “What I’ve missed”
Cover material behaves the same regardless of base material.
The characteristic changes from having either brass or German Silver as the base remains after the cover has been fitted, but the affect of the cover is unchanged (so a brass base plate will still suck out a little of the signals voltage before the resonant peak AND a Nickel cover will still do its thing – so, moving forward from here, we’ll just be focusing on German silver bases and covers, just to keep it stream lined)
If this is all an expression of conductivity between coil and string, does the “colour” matter?
It does! But only one with gold! And, the higher the grade of gold, the more it matters! To keep it brief (as brief as it can be and still contain a graph) – gold is more conductive, so gold plated covers have a greater impact on the pickup then Chrome/Nickel/black/etc (which, seemingly, don’t cause any more or less effect – even to the point of a Chrome plated/no copper cover behaving the same as an unplated cover!)
Gold, however, does, arguably, sound worse!
So covers are bad?!
Blue - Uncovered - 24.5dBV@7.63kHz
Purple - German Silver w/ Copper Underplate & Chrome Colour- 18.7dBv @ 7.21kHz
Green - German Silver w/ Copper Unplate & Gold Colour- 17.2dBV@7.37kHz
Now this ones a very loaded question, and I don’t really have an answer for you to be honest. Electrically? If I was sitting here trying to sell you a Hifi, I’d definitely say that any, essentially, cosmetic component that altered the signal to as big an extent as a humbucker cover does, is a very bad thing indeed, however, guitars/pickups aren’t hifi!
As holistic an approach as this might be, as much as this might sound like “feel good mumbo jumbo” – pickups, really, are more a case of “we like what we know” – and considering most of us will have heard humbuckers with covers (and I’d go further then that, most of us have liked humbuckers with covers, we’ve liked humbuckers with copper under plate, we’ve liked humbuckers without copper, we’ve liked humbuckers without covers and we’ve liked humbuckers with brass covers! We’ve liked humbuckers with gold covers!... you get the idea) – its just a case of horses for courses.
As a very rough rule of thumb – covers are going to make the pickup feel more rounded, softer, and less defined. (and the more conductive, the greater that effect) – its not good or bad. Its just what it is. You might absolutely love the tone of a brass cover, you might hate it. It all depends on your frame of reference I’m afraid.
Is this true for all specs of pickup?
I’ve got partial graphs for this which prove the point, but I’ll spare you those. In short, yes – it doesn’t matter if it’s a humbucker wound with 42 AWG plain enamel or 44 AWG Polysol, it doesn’t matter if its 12 screw Alnico 5 or 12 slug ceramic, it doesn’t matter if the pickup cost £300 or it cost £3, it doesn’t matter if it’s a Telecaster® Neck or a P90 or a Strat® single coil you’ve buried under a humbucker cover -the cover is always having the same general affect. Sometimes it works in the pickups favour (Historically accurate humbuckers do sound better with covers!) sometimes it works against the pickup (Epiphone® Casino P90s, even with unplated covers, don’t sound quite right!)
And I think that about covers cover and base material, in very broad strokes, but there is, I’m afraid, one more aspect to this. So, lets get it over with!
With cover material and plating options seen to, I think its probably worth while taking a look at cover “style” too. However, from our point of view, and within the scope of this kit, its not really “true”.
We offer this kit with a cover specific to the pole choices (so traditional is 6 screw poles, 6 slug, it takes a traditional cover with 6 holes, a 12 screw kit comes with a 12 hole cover, a 12 slug kit comes with a cover with no holes, you get the idea) and whilst I’m going to prove that cover style DOES effect the tone of a pickup, and its worth considering, you’ve got to remember that the pole choice on your pickup has its own effect separate to a cover.
This is because we are increasing/decreasing the amount of ferrous material within the coils. A screw pole is 3mm diameter (roughly) a slug pole is 4.75mm – a slug contains more iron then a screw – and this will increase the inductance of a pickup, which will cause the resonant peak frequency to be lower. As a quick rule of thumb, a 12 slug humbucker will be darker then a traditional and a 12 screw humbucker will be brighter – quite considerably too.
It’s a little beyond the scope of “covers and bases”, so I’ll go into greater detail in a separate section, but for the time being, know that your pole choice is having an impact AND your cover choice is having an impact.
So, for clarities sake, I’ve done these tests using a traditional humbucker, with a German Silver base – 6 screw poles, 6 slug poles, regardless of cover style, and all covers are chrome plated over copper over German Silver (again, its not the “tonal ideal” but it’s the most common composition you’ll find in the real world)
The common believe is this. “the more/bigger the holes in the cover, the ‘better’ the pickup is going to sound” – so, in theory, a 12 hole cover is going to sound better then a 6 hole cover is going to sound better then a no hole cover. And that makes sense considering what we’ve seen above, and, really, this is just an exercise in “sticking conductive material between coil and string” right?
<Insert Graph for Cover Style>
As we can see from the bode plots, on the whole, there isn’t really a great deal of difference between the 6 hole, 12 hole and “half open” covers. There are minor differences between them, but, they’re so small that you’re never going to taste those in the real world. If anything, I’m actually quite surprised that the half open cover has as much impact on the signal as the more traditional covers, simply because one coil is, essentially, open, but you can’t argue with the results, so, there we have it*.
Where we do see a difference, is with the “open” cover and the “closed” cover. The closed cover is having the greatest impact on the signal, and the open cover is having the least, but, equally, the open cover barely looks like a cover at all, so maybe that’s to be expected.
And that about covers it! (pun intended) – covers are best thought about in broad strokes, anything “with holes”, regardless of how big they may be, is going to behave the same as any other cover “with holes” (assuming all other variables stay the same), as soon as you take away the holes, you get more of an impact, and as soon as you make one massive hole, you get less of an impact (but less of a cover!) – the “myth” isn’t quite right, but equally, its not exactly wrong either.
*the “Half cover” is interesting – when testing, we’re exciting the coils through inductance coupling, with the drive coil directly over the middle of both coils. We, obviously, keep this positioning the same from one cover/base/pickup to the next. There is the potential that the half open cover will behave differently then a traditional cover, but our test isn’t accounting for that. I wouldn’t want to throw the baby out with the bathwater and say outright “half open cover makes no difference” – but, equally, if it is, and its not translating into our test? Maybe its not a big enough difference to really worry about.
**For completeness’ sake too – there are options I’ve not shown on the graph, but we have tested. The 11 Gate, H gate, Black top, the “other” H gate, the “tall” and the “3x3” covers – they all behave exactly the same as the traditional/12 hole/half open plots, so, rather then confusing the graph more then we have to, we’ve omitted them from the final results.
***All “rules” for all other variables still ring true, regardless of the cover style – so a gold open cover has a greater impact then an unplated one, a brass closed cover has more of an impact then a German silver one. Again, I’ve omitted these results for simplicities sake.
Now, all this brings me to the elephant in the room.
Covered humbuckers aren’t the same as uncovered humbuckers
Sadly so I’m afraid – the cover on a pickup is having such a big impact on the signal produced by the pickup that, really? If I was more of a purist, I’d argue that the pickup has become “a different pickup” – in the same way if I produced an uncovered humbucker with a resonant peak of 20dBv@5kHz, and then made another with a peak of 15dBv@5kHz... I’d be giving them different names, and pitching them at different roles within music.
We don’t do that with humbuckers though – we really over simplify the whole cover thing. As players, have a vague idea that something different is happening, but, really? Fitting a cover, or comparing 2 identical pickups, one covered, one not, is as drastic a change as using a completely different design of coil. The numbers may look the same, but the sound will be totally different.
However, whilst its tempting to say “they’re different pickups”, eventually (and this will happen a lot if your winding pickups!) you’ve just got to bow down to common sense. Covers are, primarily a cosmetic consideration, if someone wants your pickup, with a cover, by all means, explain the effect of a cover, but, you’ll never talk someone out of a shiny silver humbucker for their Les Paul®… trust me! I’ve tried.
Expectation vs. Reality
I’ve been going through the site in recent months, and “myth busting” a lot of stuff to do with pickups and parts, and even on this page, I’ve laid bare a lot of what’s going on with humbucker covers and how they’re going to affect your sound, both positively and negatively, and, personally, I like being honest about this stuff. If you know what to expect, then we all come away from this a whole lot more fulfilled, and no one has to sit there and gripe after falling for a marketing hype and flowery descriptions.
And in that vein (and this is a good rule for the whole of the internet!) – remember, every photo I’ve put up on this website, is “the perfect example” of what the thing should be. It’s been edited, tidied up and made to look immaculate.
Now, honestly, I wish that every single part I unpacked and stored on these shelves, was finished to the level of the ones in the photos (It’d make my life easier, and I wouldn’t have to write this!), but let’s be honest, that’s not the case.
These are, in the grand scheme of things, pretty affordable parts – they’re well made, well plated and generally, higher end examples of what they are…. But they’re still “affordable” – it’s a £5-10 humbucker cover, right? Go into buying this stuff, knowing that, if you look closely enough, you will find something wrong with them. There are ALWAYS minor imperfections in guitar parts.
That’s not to say that the majority of covers won’t be “very close” to perfect, nor is it to say that we wash our hands of “real” faults, but I do have to ask, that we all have some realism with this stuff. It’s a £5 cover – its not a £50 cover (although I doubt, they’d be any better) – expecting superior grade, faultless electroplating, 24 carat gold, tolerances down to 0.001mm, or whatever, is wholly unrealistic. I appreciate that you may be fitting these to a pickup that you’re selling for £500… I appreciate you might have a really picky customers yourself, but Axesrus® does have to draw the line somewhere.
We will not replace covers with what we consider normal levels of imperfection.
We WILL accept them as returns, and refund as per our Ts & Cs in regards to “unwanted goods”
I’m not saying these covers are cheap, second rate, and riddled with flaws you understand? They are, really, some of the best covers I’ve worked with, and we do have a very high level of quality control both at manufacturing, and in house when picking and packing. But, really, no one is spotting an isolated a 0.25mm “dimple” or “divot” in a finish, or a 0.5mm scuff. (and that’s how small these flaws are!).
And remember too (and this is scant consolation to anyone making pickups for a living, because you will suffer this just as badly as we do) – minor imperfections that look minor on the part, vanish once the part is fitted to a guitar. We’re damned by looking at this stuff under the microscope of isolation, and, in reality, that £10,000 guitar you’ve got hang on the wall? I guarantee, has exactly the same manufacturing imperfections in its parts.
So, with that said, and in an effort to be WHOLLY honest, here’s a what I’m talking about.
Heres a photo i've taken, of a Chrome humbucker cover, under harsh light, taking absolutely no consideration to the reflections, and i think we can all agree, that its faultless. If this was on my desk to be checked for an order, its going out, no problems what so ever.
What do we have here?! its a 0.5mm "line" in the base metal, which has shown through into the finish. Its only visible when the light catches up. This is what i consider to be a realistic imperfection, and whilst i'm not saying it should be expected, i cant in good conciousness, say its a fault. Its pretty much what i'd expect from a lage, flat piece of electroplated metal frankly.
Close up #2
I was "lucky" here, and this acts as proof that you'll always find something if you get close enough, this cover has a 0.25mm "scuff" above the E pole hole - again, its miniscule, and again, not to be expected, but your probably better off accepting that these things will happen.
Why is Black rare?
Good old Matt Black - I've alluded to this in the "colours" secion, but black is an absolute nightmare of a finish when it comes to electroplating. Its soft, its prone to marking, and its diffuclt to clean out. We recieve all of our black parts in a "grease" to "protect" them. I have absolutely no idea what that grease is, or what function it serves. Under that grease, lives what you can see in the photo. It is dog rough - however, it is not faulty!
Just needs a clean
Bit of a rub with a soft cloth and a degreaser, and its back to perfect (or as perfect as any of this stuff actually gets) - handy hint if your working with black hardware/electroplating - sun cream! For some reason i dont understand, sun cream rubbed on then rubbed off, gets them looking absolutely amazing.
Unplated means "From Factory"
Again, i've gone into greater detail with this under the "colours" section, but, raw is raw! Get up close, and it is scratched, scuffed, marked, stained and, frankly, a bit rough! This is, again, normal. These parts, up until recently, weren't intended to leave the factory unplated, and the recent trend for "pre-aged" and reliced guitars/parts has brought them into the spotlight, but be under no illusion. A raw cover is not a "finsihed" part - it hasn't been handled gently, it hasn't been polished, it is rough!