Some information on pickup theory, design
& how the pickup maker works their craft
Handwound, Scatterwound or 'Vintage' Pickups?
Are they better?
In recent history is was 'discovered' that pre-corporate takeover Fender® and Gibson® pickups were more musical and rich sounding, with clearer highs & lows and less mud & ice-pick! This, it turns out, was down to lax quality control measures in the old days, and inconsistencies produced some great (and some less-so) pickups. Analysis of some of the great pickups revealed their secrets:
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Coils were hand-wound - uneven winding patterns altered the capacitance of pickups, letting more frequencies through. Modern pickups are generally wound on automated machines, laying down the strands of wire in a very uniform pattern. Hand winding, which would more accurately be described as hand feeding of the wire using a motor driven winding machine, lays down the wire in a more scattered way. My method of using a Hand-cranked winding machine exacerbates this effect.
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Inconsistencies in magnets used - before the standard Alnico 5, now in most quality pickups, Alnico 2, 3 & 4 were also used, giving different musical properties - see below.
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Humbucker coils were mismatched - more or less winds between adjoined coils, again allowed more frequencies through.
By using the specifications of those coveted old style pickups it is possible to recreate some of those sounds from the golden era. It is also possible to create more modern sounds, but with greater musicality. Many small companies exist which specialise in these types of boutique, high quality pickups. Fletcher Pickups produces hand-wound, handmade pickups using a hand-cranked winder, Quality coil wire sourced from Europe and only Sheffield-made magnets.
Choose your magnets
There are two types of magnets commonly used in pickups; Ceramic & Alnico.
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Ceramic magnets are cheap, strong and most common in the cheap pickups we all know & hate. In those cheap pickups claiming to be PAF style or classic etc, they sound muddy & dull in the neck and shrill & piercing in the bridge. However, if your style is high gain, over-driven, distorted wall of noise - strong magnets in overwound, well made pickups shows what ceramics are for.
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Alnico are a mixture of Aluminium, Nickel & Cobalt, and are a more expensive & weaker magnet. These are used in better quality commercial pickups and these pickups can sound beautiful. They are available with differing proportions of the metal mixture, as Alnico 2, 3, 4, 5, 6 & 8, each with their own use.
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Sandcast bar magnets used in p90s and Humbuckers were used in some of the oldest pickups including PAFs. Their rough, unpolished surface produces slightly uneven magnetic distribution, resulting in a slightly smoother, less focused sound with a slight trimming of the top end.
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UnOrientated bar magnets were later used on some Humbuckers and p90s. During the solidification of the AlNiCo alloy, strong magnets align the crystals within north-to-south, orientating the magnet, giving it a 'defined sense of direction'. Unorientated magnets miss this step, resulting in a chaotic distribution of magnetic flux. Magnets are still charged North-to-South, but the focus of the magnetic field is wider. This results in considerable smoothing of the tone produced, with significant levelling of the top end produced, though retaining most of the strength associated with the alloy.
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FeCrCo
Alloy of Iron, Chromium & Cobalt with magnetic & tensile properties Very similar to CuNiFe, often called New CuNiFe (some forget to put new!)
Currently the only substitute to CuNiFe
CuNiFe
Relatively weak, but strong, machinable magnets not made for decades. Found pretty much exclusively on WideRange pickups
The lack of a steel poles give a quick, bright and brash voice.
Neodymium
Ridiculously strong magnets!
Can be used for Massive Sounds, with Ultra clear top ends in the Hottest of pickups.
Basically childish, but surprisingly playable in the right context.
Who needs Active Pickups!
Ceramic
High power & string-pull, and generally hard to make work well with clean tones, these are for pickups designed for aggression over musicality.
If your guitar is used to scream in peoples faces, use these.........or why not go mad and use rare earth magnets, it'll either work or break something!
Alnico 6 & 8
Found between Alnico 5 and ceramics, 6's & 8's have strong highs, full mids and reasonable lows with sharp attack.
Alnico 6 is darker than 8, which has a pronounced top end.
This comes at the expense of sustain due to the high magnetic pull. A reasonably uncommon magnet in commercial pickups.
Great for over-driven in your face sound, but with a bit more versatility and musicality than ceramic.
Alnico 5
Found in the majority of good pickups, this is the go to magnet.
A stronger magnet with pleasant attack, clear highs and scooped mids and manageable lows.
Perfect for modern sounding guitars where both proper grunt and true clarity are needed out of one instrument.
That sound of the 60's single coil. Clean and dirty!
Alnico 2
A weak magnet with low string pull for great sustain. Smooth attack and low output, typical of that 50's sound.
Great for single coils, classic twang and articulate humbuckers.
Great paired with Alnico 5's on a single coil bridge to mellow the tone of the unwound strings.
Alnico 4
Described as a flawed Alnico 5, with strength and pull between a 2 and a 5. This magnet tends to give an even response across the frequencies.
In my opinion it's the best magnet for that PAF humbucker sound.
Really clear and sweet sound, with a bit of grunt if you light it up.
Alnico 3
The weakest magnet with lowest amount of string pull. Used in some old P90's but hardly ever used in commercial pickups.
Delivers the greatest sustain, as it has the least string pull, a smooth attack and warm mellow tones.
Used in some of the very earliest pickups, including the first p90s.
So, how does a Pickup work?
A guitar Pickup is a Transducer; it changes energy from one form to another - Kinetic string vibrations into electricity.
A guitar pickup always comprises of a Magnet and a Coil of thin wire.
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The magnets acts to magnetise the guitar strings with an opposite polarity of the magnets. These vibrating magnetic strings flux the magnetic field and excite the electrons within the coil, pushing them forwards and backwards as the string oscillates forwards and backwards.
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This produces an Alternating Current (Current is the flow of electrons). The more coil there is, the more electrons are induced to move - makes sense then that a coil like this is called an inductor.
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The relative thinness of the coil wire causes drag on the electrons; in simple terms this is called resistance in a DC circuit and Impedance in this AC circuit of a pickup. The flowing electrons through the coil are resisted and a Voltage is produced (voltage is the difference of electrical energy between two points, in this case, the start and end of the coil(s)).
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In parallel to this inductor/resistor, there is capacitance: The coil of wire has the ability to affect electrical energy through interactions of the electrons, between adjacent wires within the coil. Although the value is very small compared to the capacitors you use to affect your Tone pot, it is part of the whole, and though not controllable to the same extent as magnets and wire, does play a significant part in the nature of the pickup and play a large part in why hand wound pickups sound different.
So knowing this, we can change parameters of the system to affect the energy coming out the pickup: Change the Tone!
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Magnets: Alnico 3 sounds different to Alnico 5 right? Kind of! Magnets will affect the way the vibrating strings interact with the coil and should be considered holistically. The general rule is (for AlNiCo at least), the stronger a magnet is, the more efficient the system is, the brighter the tone produced will be - more emphasis on the brightness/treble. Ceramic tends to lose a bit of treble in favour of mids.
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Inductance: Generally speaking, the more inductance, the darker the tone (and obviously louder too). This is done by adding more wire to the coil - to make the pickup hotter. This will increase the Resistance in Ohms. Using stronger magnets will counter the darkness of adding more inductance, resulting in more balance and louder pickups.
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Steel: Where the magnets are placed/how the strings are magnetised also affects the tone. Single coils, with a magnetic pole directly below the strings are very efficient at magnetising the strings and produce a quick bright tone. p90s or Humbuckers pass the magnetic pull through a steel intermediary - poles/slugs - which increases the inductance within the coil, producing a warmer tone and smoother attack.
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Resistance: More Resistance Means Hotter Pickup, Right!! No! No it doesn't. Most pickups commercially available are measured or compared using the resistance of the coil wire - that it, the degree to which the wire resists the flow of electrons through it. This is measured in Kilo Ohms. This is the case, largely because this measurement is very easy to obtain. Although broadly speaking this is fine, the value of this measurement is not very helpful to determine how a particular pickup will behave as it only really tells you information on how much wire is on the pickup.
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Increasing the resistance, without increasing the inductance will increase the voltage and produce a slightly darker tone. I use three gauges of coil wire - 0.05, 0.056 & 0.063 mm in diameter. Hotter pickups will require thinner wire just to fit the coil onto the bobbin, exacerbating the inherent darkness of higher inductance. However, using a thinner wire in a very bright pickup (without increasing the number of coils/inductance) can be used to tame a bright top end - Useful on a Telecaster bridge or Trons.
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Capacitance: Interaction of electrons between the coil wires, also known as the skinning effect, can increase capacitance and effect the tone, making the pickup seem dull as electrons/signal is drawn away from the signal path. Effectively it sounds like part of the signal is not getting through as much as other parts - the shrill, ear piercing treble of a bridge pickup which seems to be lacking in mids/bass, or the mud of a bridge pickup without any treble. Reducing the tension in the coil and winding in a pattern where the wires are not uniformally side-by-side, reduces the opportunities for electrons to interact with their neighbours. This is the greatest secret of Handwound pickups and what gives them their characteristic Bright & Musical Tone!
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Pickup Height: The balance of treble to bass will change disproportionately with changes in height of the pickup to the strings. The further away from the strings, the more bass is lost (pickups sound brighter). This is especially noticeable in mismatched pair of pickups; a hot pickup in the bridge will sound harsh and tinny when balanced (for volume) with a vintage style pickup in the neck.
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Anything else?: Yes, lots of subtle parts of the whole, such as compression, component materials, potting, coil shape...... That's just on the pickup! Things like guitar strings, cables & the complex world of Amplifiers need all be considered too!
So how can this information be used to Get Your Tone? Well, that is the skill of the Pickup Maker and why we like a lot of adjectives! I take words like; Vintage, Smooth, Clear etc......... and apply them to the principles outlined above and with a tweak here and there, we can get you to your happy place!
Measurements
I try to show measurements for all of my standard spec pickups, including Resistance & Inductance, to guide you and will add individual pickup data to each order.
Resistance is measured in kOhms at 100Hz AC - AC is more representative than commonly used DC measurements, as pickups work in AC.
Inductance is measured in Henries (H) also at 100Hz
I also measure capacitance within the coil and will add this data to individual orders. Measure in pico-Farads (pF) at 100KHz.
Production tolerance of standard spec pickups should be within +/- 10% of the values stated.