If ya read...
Ya see a lot of discussion about magnets...
Some items leave a person with Beeeg question marks in a thought balloon...
A few minutes ago my wife hands me a box with the three pickups from my Peavey Raptor.
Says to I "Do these need to be in the bathroom?"
Hadn't seen them in maybe 5 years...
Whilst looking at them I noticed their construction I noticed that rather than having magnetic poles, they have rods through the bobbin with a common magnet on the back... Can I hear some pros n cons about this and some discussion from people that have put a lot of time into experimenting with the array of magnetic materials available today, yesteryear and beyond?
How about it alla you experienced musicians...
Please educate me, right now I resemble this guy...
Please help me remove the screwball from my head...
Yeah, Thom, that is how my Peavey pickups were made. So were the Fender pickups I put in the Raptor. (69-75, I think)
I think that is how most single pickups are made.
One of them will stick to the two others, or the magnet will be a different color. that is the reverse wound reverse polarity center pickup. It helps combat hum, so when in position 2 or 4, you have a humbucking effect.
They all also use individual Alnico magnets of varying strength, in place of the "slab" type magnets.
Over the years, the slab, or ceramic magnets get weaker, resulting in the vintage sound that we like. less pull on the strings, and can be set closer to the string.
Note; Fender used NSN and SNS polarity in different years. You can use a compass to determine the north pickups from the south ones.
__________________
"I would challenge anybody to come up with a better design for a guitar. The Stratocaster is as good as it gets."
Eric Patrick Clapton
"I'm a tidy sort of bloke. I don't like chaos. I kept records in the record rack, tea in the tea caddy, and pot in the pot box."
George Harrison.
Last edited by Stangmaster; Nov 20th 2009 at 12:50 PM.
rule of thimb has it that the bar magnet below the inert slugs is that those are ceramic magnet pickups. some would have it that the sound a tad harsh, tho i've not seen any viable proof of this. then you get into the differing thoughts on alnico magnets, III being smoother and brighter than IV, V being smoother than the above, etc. bottom line is, if you like the sound coming from your guitar, then the pickups work just fine. where it really matters is in a true vintage reproduction, alnico is vintage, ceramic is more modern.
Just to add a bit more on the subject. there are several types of magnets used in pickups, early on alnico magnets were used mostly and these came in different "grades", alnico II, III, IV and V, as ghostwolf has mentioned, all claimed to add slightly different properties to the pickups sound. (Most vintage Fender and Gibson pickups had alnico magnets).
Ceramic magnets have generaly been used in high output pickups and in many cheaper pickups. Early custom pickups such as Di Marzios, original "Super Distortion" pickups back in the 70's used ceramic magnets. (they still do) Pickups like the Super Distortion were considered very "hot" pickups back in the day, but many of todays ceramic magnet pickups, particularly those favored by "metal" guitarists are maybe 50% hotter again. Many Fender made In Mexico pickups have ceramic magnets, those are the Fender ones with the bar magnet running the length of the bottom of the pickup. Most Fender pickups use the magnets as the pole pieces set in the pickup bobbins.
Samarium Cobalt is a more recent magnet material used by some pickup makers, Fender uses them in some of their "Noiseless" pickups.
So magnets apparently influence the sound or tone of a pickup, but there are other factors involved, such as the guage and type of wire used to wind the pickup and how many turns of wire are wound onto the pickup bobbin. You'll often see the term, "wound hotter" in pickup descriptions, meaning more winds of wire to increase resistance. It can all get very complicated!
Do doubt some pickup makers and "tone hounds" could argue about pickup construction, wire and magnets for hours, but the fact is that the sound that comes out of them is all that matters to most of us.
__________________ I started making guitars because no one made the guitars I wanted, but every time I finish one I think I want something else! Rob
Last edited by eon; Nov 21st 2009 at 04:49 PM. Reason: correction
The ceramic bar magnets tend to get weaker, resulting in the "vintage" sound- smoother. If you over wind, that is to add windings, they become more sensitive, but still retain their smoother tone. Sort of like using a base plate.
Older pickups still sell for good prices on ebay.
Noiseless pickups sound like older ceramics, that smooth tone. Different Noiseless have more or less windings.
Read Seymore Duncan's Webpage. He also worked for Fender, Repaired the pickups and electrics of Clapton and other Yardbirds like Page and Beck, while he worked for Fender in Britain.
(Run on sentence)
__________________
"I would challenge anybody to come up with a better design for a guitar. The Stratocaster is as good as it gets."
Eric Patrick Clapton
"I'm a tidy sort of bloke. I don't like chaos. I kept records in the record rack, tea in the tea caddy, and pot in the pot box."
George Harrison.
Last edited by Stangmaster; Nov 22nd 2009 at 06:34 AM.
When speaking of Ceramic P/Us you're talking about Humbuckers. Fender never used Ceramic P/Us on Strats. Only the Japanese el cheapo P/Us were the Ceramic bar across the the bottom and those are garbage! Fender uses Alnico V mags and used some Alnico III in the early 50's. Note the the two pickups below (bridge and middle) the slab bar magnet, this is a less expensive method of making single coil pickups only used by imported guitars to keep costs down.
It is best to replace these with alnico type pickup designs.
There are some benifits, mostly personal preferamce:
"
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Guitar Wiring and Pickup Modifications
Using a little ingenuity and a few inexpensive parts, there is a great deal of scope for customising or "hot-rodding" your guitar to dramatically increase the range of tones it can produce.
Before I get into the nitty-gritty of how to chop up your wiring of your guitar, I shall take a brief look at some of the principles involved in the function of typical guitar electronics, including pickups and the various components inside your guitar, and how each of them will affect the instrument's tone.
How guitar pickups work
A guitar pickup is a very simple electro-magnetic device, which would be instantly recognisable to Michael Faraday, the great pioneer of electromagnetism.
Construction of a typical single coil pickup
Construction of a typical single coil guitar pickup
In its simplest form, the standard "single coil" guitar pickup, as fitted to Tele or Strat style instruments, the pickup consists of (usually) six permanent magnets, with several thousand turns of fine copper wire wound around them. To those of you who still have a distant memory of physics lessons in school, this should bring to mind the definition of a basic generator or dynamo - "The production of an electrical potential difference (or voltage) across a conductor situated in a changing magnetic flux". The vibrating steel string cutting the lines of magnetic flux causes the change in flux in the "conductor", ie the coil of copper wire.
As guitarists who use instruments equipped with single coil pickups will testify, they are equally effective at picking up stray 50 or 60Hz fields radiated by AC mains wing and equipment as they are at picking up the vibration of the strings! I am sure we have all ended up playing our guitars in weird and wonderful positions, just to minimise the infernal buzz! This led to the development of the "humbucking" pickup. This is again a simple device, imagine two single coil pickups placed side by side and both connected in series - if these pickups were identical, then they would both pick up the same amount of string vibration and background hum: the voltages would be added together but the ration of signal to noise would be the same.
Construction of a typical humbucking pickup
Construction of a typical humbucking pickup
The clever twist that makes the humbucker so effective is that in, one pickup, the permanent magnets are effectively mounted upside down (usually there is only one bar magnet with the North pole touching the base of one set of polepieces, and the South pole touching the other set), and the coil is reversed. This effectively means that the signal produced by the vibrating string is unchanged, whereas the hum signal produced by pickup of stray magnetic fields is reversed (remember that the string signal is produced by the interaction of the magnet and the coil, but the hum is purely picked up by the coil). When the signals from the two coils are mixed together, the signal from the vibrating strings is effectively twice that of a single coil, but the hum signal is reduced to almost zero, as the hum signal from the two coils have opposite polarities. In practice, there will still be a small amount of hum, as the two coils are very rarely identical.
Factors Effecting Tone
For such a simple device, the tone of a guitar pickup can be affected in both subtle and not-so-subtle ways by a large number of factors.
1 - Magnet Material
The magnets are at the heart of the pickup and the material used will have a great bearing on the sound of the pickup. There are three main types of magnetic materials used:
* Alnico - Aluminium Nickel Cobalt
Alnico was the first type of alloyed magnetic material and the oldest member of the magnet family. First developed in the early 1940's it is made by mixing aluminium, nickel and cobalt with iron and is particularly suitable for temperature sensitive applications.
Traditionally used in "Classic" and "Vintage" pickups, alnico magnets are associated with mellow tone, a smooth response and a moderate output. Some disadvantages of Alnico are that the strength of a magnet will gradually decline over time (possibly explaining some of the "mojo" attributed to vintage pickups?), and that they are subject to corrosion from damp conditions and sweat.
* Ceramic or Ferrite - Strontium Ferrite
Hard ferrite magnets, sometimes called ceramic, were developed as a low cost alternative to metallic magnets and have been manufactured since 1954. Strontium is combined with iron atoms to form a magnetic compound that is stronger than alnico and has much better corrosion resistance than rare earth.
Because of its lower cost, ceramic magnets are frequently used in budget instruments. The lower magnetic strength makes them less prone to causing "string pull", which can cause intonation problems or "warbling" tones when the strings are close to the pole pieces. Tonally, pickups with ceramic magnets usually have a brighter sound than those using alnico.
* Rare Earth - Neodymium Iron Boron or Samarium Cobalt
Known also as 'super' or 'neo' magnets and commercially available since 1984, rare earth magnets are the smallest and most powerful of all permanent magnets.
Although more expensive than ceramic, rare earth magnets are 5 to 7 times stronger. They provide high energy, maximum efficiency and extreme stability when exposed to other electromagnetic fields.
Rare earth magnets are used in some newer pickup designs and quite often in soundhole mounted pickups designed for acoustic guitars. They are also used in some "active" pickups where the combination of high magnetic strength and small physical size allows the designer more space for fitting in the active circuits."
__________________
"I would challenge anybody to come up with a better design for a guitar. The Stratocaster is as good as it gets."
Eric Patrick Clapton
"I'm a tidy sort of bloke. I don't like chaos. I kept records in the record rack, tea in the tea caddy, and pot in the pot box."
George Harrison.
When speaking of Ceramic P/Us you're talking about Humbuckers. Fender never used Ceramic P/Us on Strats. Only the Japanese el cheapo P/Us were the Ceramic bar across the the bottom and those are garbage! Fender uses Alnico V mags and used some Alnico III in the early 50's. Note the the two pickups below (bridge and middle) the slab bar magnet, this is a less expensive method of making single coil pickups only used by imported guitars to keep costs down.
It is best to replace these with alnico type pickup designs.
[edit]Whats up with that neck pup??? ^
Fender MIM Standards have always come with them, slightly different, ceramic bar magnets on both sides of the pole rods.
People beat ceramic pups up pretty bad, but I just dont see it, having owned both the MIJ ceramics as well as the MIM ceramics. The MIJ ceramics sound vintage like, mine may have degaussed over time when Id purchased it, and I say this because the MIM sounded hot, almost a Clapton type driven tone(mild break up), but if you roll off some of the volume to between 8 and 9 they clean up nicely...so I dont get it
I think its just a different flavor, and a flavor you might not like....but I find myself kinda missing my ceramics and my MIM standards as well as kinda chasing that kinda tone with my alnicos.
(dont get me wrong, I love my current guitars and pups, but I do find myself missing those tones....so I really dont get how ceramics are inferior in anyway... besides price point, and thats kind of a plus)
[edit]on a quasi related note: I didnt need to shield the MIJ Standard, but always hear an improvement on MIM Standards with shielding.
Last edited by Sprocket; Nov 23rd 2009 at 02:17 PM.
There are positives for any pickup, it just depends on what you are looking for. What sounds good to one, another may howl at. I like blues/rock, someone else may like classical. Even someone else may like metal. (Not me.)
__________________
"I would challenge anybody to come up with a better design for a guitar. The Stratocaster is as good as it gets."
Eric Patrick Clapton
"I'm a tidy sort of bloke. I don't like chaos. I kept records in the record rack, tea in the tea caddy, and pot in the pot box."
George Harrison.
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