If you're into guitar or bass guitar pickups and mods, you probably hear the words "AlNiCo" and "Ceramic" a lot. These terms refer to the magnetic bar located inside the actual guitar pickup of your guitar. Most guitar manufacturers mention the pickup types they use on each guitar model but some don't. We will see how you can spot an AlNiCo or a Ceramic pickup and let you choose the best pickup type for your guitar.
What does an AlNiCo magnetic bar look like?
The Al.Ni.Co. magnetic bar is made out of Aluminum(Al), Nickel (Ni) and Cobalt (Co) or Copper(Cu). That's why the Alnico magnetic bar is usually silver colored.
Here are a few pictures of Al.Ni.Co magnetic bars:
The cylinder magnetic rods (polepieces) are placed inside the plastic bobbins of a pickup. Here is an exploded view of a single-coil pickup with AlNiCo rods:
Bottom view of an Al.Ni.Co. single-coil pickup
The magnetic rods are mostly used on single coil pickups. There are some dual-coil pickups that use magnetic rods though.
The magnetic bars can be used for single and dual coil pickups. In this case, the magnetic bar is placed under the pickup bobbins, not inside them. This is a bit tricky as the magnetic field produced by the bar cannot usually reach the upper side of the pickup by itself. Therefore, the magnetic field of the bar reaches the top of the pickup through the bobbin poles or rods. The poles/rods of these pickups are made of metal. Some pickups use metallic rods, others use metallic screws, hex bolts, metallic rails and any combination of these. The metallic poles-bolts can be usually adjusted in height to get closer to or farther away from the electric guitar strings. This adjustment can improve the dynamic response, tone and output of your guitar.
Here's an exploded view of a pickup that uses magnetic bars instead of magnetic rods:
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An exploded view of a "humbucker" dual coil pickup:
Alnico pickup types:
There are a few grades of Alnico magnet bars. Alnico II, IV and V type material are used on most guitar pickups. The Alnico II magnets are a bit weaker in terms of magnetic field strength than Alnico IV and V bars. Therefore, an Alnico V pickup sounds hotter and more powerful than the same pickup equipped with an Alnico IV or II bar. Alnico II pickups sound cleaner than Alnico V pickups of the same kind. Nevertheless, there are many more parameters that determine the output power and overall tone of a guitar pickup. That's why I compared the same pickup using an Alnico V and Alnico II bar.
Here a few parameters that are taken into consideration when building a guitar pickup:
The pickup coil material, the number of turns of the pickup coil, the size of the bobbins, the number of coils, the position of coils, the coil wire diameter, the magnet type, the position of the magnet, the size of the magnet, the strength of the magnetic field, the top and back covers of the pickup, the rods inside the bobbins, the wax used to seal the pickup and many more parameters can affect the tone of a guitar pickup.
For instance, these two pickups are way too different in terms of bobbin size, coil turns, polepieces/rods and magnet bars. Therefore, these pickups will also sound different:
Ceramic pickups:
The ceramic pickups are made just like the Alnico pickups we've seen before. The only difference here is the material used to build the magnetic bars of the pickup.
What does a ceramic pickup bar look like?
Well, the ceramic bars are usually black. The look like graphite. Here are some ceramic magnet bars:
There are only a few ceramic pickups that use magnetic rods instead of bars. Most ceramic pickups use ceramic bars. Unlike AlNiCo single-coil pickups, the ceramic single-coils usually have a ceramic magnet bar glued at the bottom of their plastic bobbin. Here are two examples:
The dual coil ceramic pickups are built exactly like their Alnico counterparts. The magnetic bar is made of a "Ceramic 8" material in this case. Here's an example of a pickup using ceramic bars:
So, what are the differences between Alnico and Ceramic pickups?
We already mentioned that there are quite a few parameters one has to take under consideration to define the tone of a pickup. So, let's say that the same pickup is available on the market with a ceramic bar and an Alnico bar. Which pickup will sound hotter and more powerful? The answer is: the one with the stronger magnetic field! If the Alnico V and ceramic bars have the same size and volume, the ceramic magnet is usually a bit stronger. That's why the exact same pickup will sound a bit hotter if it uses a ceramic magnet instead of an Alnico one.
The increased strength of the magnetic field will result in more output voltage, more bass, more sustain and more picking sensitivity. That's the reason why "ceramic 8" bars are widely used on pickups made for rock, hard rock and heavy metal music. There are lower output pickups though that use ceramic magnets for other reasons (e.g. a different frequency response or dynamics). Alnico pickups usually sound cleaner, with more dynamics, more treble and mids and more picking attack instead of note sustain. So, now you can choose between the alnico and ceramic version of the same pickup.
But, what if the pickups are different in other ways? What should I look for?
Pickup companies have specs and charts for most of their production pickups. Here are a few specs that will help you choose the right pickup for you:
1) Pickup output: The output voltage is usually measured in mV (milli-Volts) or rated "hot", "medium", "soft". A pickup with 100mV of output voltage is hotter and more powerful than a pickup with a 50mV output.
2) Pickup resonance frequency. This is the frequency were this particular pickup resonates. This it the freq. point were the pickup sounds hotter and is prone to feedback. A higher resonance frequency pickup will have more treble and mid power than bass.
3) Bass/Mid/Treble or pickup EQ. These numbers will tell you more about the frequency range and response of your pickup. A pickup with B/M/T = 9/5/3 will sound darker and bassy compared to a pickup with B/M/T = 4/6/9 that will sound brighter, clearer, treblier with more mids and more "focus".
4) DC resistance. This is the resistance of the pickup coils. More coil turns result to larger dc resistance. Larger number of coil turns means more output power and voltage. The number of coil turns also affects the tone of the pickup and its freq. range. With a lower number of coil turns you get treble and attack instead of output power, bass and sustain.
Here are a few pages with more info on pickup specs:
http://www.seymourduncan.com/comparetones
http://www.dimarzio.com/pickups
Gibson relative pickup output chart:
Extra:
Father time and catch up with old Alnico pickups!
Alnico pickups tend to get weaker and weaker over time. The strength of their magnetic field gets lower. Ceramic magnets usually last longer than Alnico ones. Some guitar techs can actually restore the magnetic field strength of an Alnico pickup. A useful tip here is NOT to store ceramic and Alnico pickups together. Alnico pickups could get weak due to their interaction with other pickups.
Guitar pickups are usually connected to potentiometers, switches and electronics. We'll see more about these controls and how they affect the tone of a guitar in the next article!
-Thanos
guitardreamer.gr@gmail.com
thankyou...I have never read anything as clear and easier to understand as this.
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