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Where to get Alnico 2 magnet bars and rods?


Ricochet

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I'm conducting a little experiment on my old Epiphone '57 and Hot humbuckers. I'm curious if I'll get a sound improvement(#-o) if at all by replacing the magnet with a different magnet bar.

I see Alnico 5 and ceramics in abundence, but no Alnico 2, or 3 and 4 for that matter. Anyone know?

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So you're doing some Seth Lover experiments? I hope we

can hear about the results....anyway Jason Lollar, apparently gets

his magnets from "Duramag". Don't know if Gibson/SD get them from the same

place, but you can try contacting them and see if they will sell you

a bar magnet or two. Most manufacturers don't want to deal with

small retail sales like that..but you never know.

 

http://www.duramag.com/alnico.html

 

Stew-Mac also sell everything else for pickups except the bar magnets.

Problem with magnets is the shipping. Has to be ground only (I believe)

and the postal services may not accept them.

 

Stew-Mac also sell the Schatten Magnet polarity tester #5127 ($9.00), but

if you know how to use a compass, you can get by with using a compass

to test the N vs S poles of the bar magnet. (Poles with are alike repel

and poles which are opposite attract).

 

 

Here's a site that Jason Lollar has been known to post to:

http://www.mimf.com/archives/make_pickups.htm

 

hope this helps you out.

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So you're doing some Seth Lover experiments? I hope we

can hear about the results....

 

Thanks Dan, that helped a lot. Yeah, no new or fancy stuff. Just wondering if I can get any noticable results. The Epi-pups are basicly paperweights, might as well turn'm to good use. If it yields any astonishing results I'll be sure to share. I reckon I'm not the only one with a spare set of Epi-buckers...

First I'm thinking of changing magnet-bar-types. Then I'll swap a '57 coil with one from the Hotch and the other way round.

And finally replace a coil's polepieces with individual magnet rods/no bar. Who knows, I may do the other as well.

The biggest challenge will be recording the results(=my playing)...#-o

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Thanks Dan' date=' that helped a lot. Yeah, no new or fancy stuff. Just wondering if I can get any noticable results. The Epi-pups are basicly paperweights, might as well turn'm to good use. If it yields any astonishing results I'll be sure to share. I reckon I'm not the only one with a spare set of Epi-buckers...

First I'm thinking of changing magnet-bar-types. Then I'll swap a '57 coil with one from the Hotch and the other way round.

And finally replace a coil's polepieces with individual magnet rods/no bar. Who knows, I may do the other as well.

Biggest challenge wll be recording the results(=my playing)...#-o [/quote']

 

I got 4 from my EmpIIs...basically dead weight right now. Let me know if you want

them. I'll gladly get rid of them..don't know how much the shipping would be.

I got GFS Pups through the postal service with no problems, but they were packaged

in little cardboard boxes and then in a larger box..labelled as "repair parts".

 

The other thing you need to know about these pickup bar magnets is that they could be

isotropic or anisotropic..that is a term for the way the alnico "grain" of the magnetic material

is oriented before they run them through the magnetizer. Also ,alnico II specs indicate a relative field strength

vs the field strength of Alnico III, IV and V so it depends on how intense the magnetic field is

in the magnetizer as well, although the composition of the magnet will probably determine to what magnetic

strength the actual bar can be magnetized... and retain that magnetism after being removed from the

magnetizing machine.

 

 

I also read somewere that Gibson magnetized and polarized their magnets for Alnico II differently from

some of the other manufacturers for their P-90s..on the shorter dimension of the bar as compared

to the longer dimension, and this could make some difference in the magnetic field around the coil.

 

It's a real witches brew and some proprietary secrets that probably will not be available. Lets face

it, if everyone freely gave their "secret recipies, all the pickups out there would be more or

less the same.

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Thanks Dan, that is very generous of you. I'll be sure to take you up on that offer(I'll PM you tomorrow)

 

Pickup manufacturing is really applied science! I have a basic concept of what iso- and aniso-tropic are. I think Anisotropic magnets like Alnico 5 and 8 have stronger magnetic properties in a given direction. Because during the manufacturing process, a magnetic field is applied to orient the material and increase the magnet's strength. This pre-magnetizing process is not applied with Alnico 2,3, and 4. Hence the weaker magnet strength and the lack of a 'natural' magnetic orientation.

 

I get kind of lost if we are talking about Henries and how they are relative to Gauss....Never mind the Oersteds and Iersteds!:-s

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Pickup manufacturing is really applied science! I have a basic concept of what iso- and aniso-tropic are. I think Anisotropic magnets like Alnico 5 and 8 have stronger magnetic properties in a given direction. Because during the manufacturing process' date=' a magnetic field is applied to orient the material and increase the magnet's strength. This pre-magnetizing process is not applied with Alnico 2,3, and 4. Hence the weaker magnet strength and the lack of a 'natural' magnetic orientation.

[/quote']

 

Yes, the manufacturing process (from what I've learned on the subject) also involves

other trace elements to add to the mixture..and this has some effect on the field strength.

Here is link that describes the properties of magnets and relative magnetic strengths.

http://www.coolmagnetman.com/magstren.htm

 

So if you read some of this magnet experiments, you will have a bit better idea, but

there are quite a few metallurgical and magnetic formulas that are not mentioned.

The formulas are important in the science of magnetics, but very few understand

them,and for the most part we don't need to..we just use the finished product.

http://www.coolmagnetman.com/magstren.htm

 

So after reading some of this material, we know have a better appreciation that

in making pickups there is a lot of experimentation and analysis of pickup response

involved before you come up with a winner.

 

Magnet& coil winding experimentation is a bit analogous to the "WD40" brand spray lubricant

we are familar with. ....what happened with WD1-WD39? #-o

 

Here's a good link with some details on Alnico magnets:

http://www.magnetsales.com/Alnico/Alprops.htm#magnetic

 

 

I get kind of lost if we are talking about Henries and how they are relative to Gauss....Never mind the Oersteds and Iersteds!;)

 

Henries (H) is the electrical term for Inductance of a coil and has a direct relationship

to the resonant frequency of coil. But in a pickup, we are also dealing with the

R (resistance) of the copper wire which we know by the familiar term of coil

resistance. #42 copper wire comes out of a die with a minium/average/oversize

diameter depending on the individual die and the temperature of the die.

 

Here are some values from an Epiphone listing on pickups:

Gibson Burst Bucker II Alnico II (pickup relative output=6.75) 8.4Kohm Inductance=4.963H

Gibson BB III Alnico II ( " " " =7.75) 8.8K I =5.38H

Gibson Tommy Iommi Alnico II+ Ceramic (" =9.5) 16.5K I =11.5H

Gibson P94T Alnico V ( =7.5) 9.1K I = 6.48H

Gibson P-94R Alnico V =7.0) 8.1K I = 5.95H

Elitist 50SR/50ST Alnico V ( " =6.5) 8.5K I = 4.45H

Elitist 60ST Alnico V ( " =7.0) 13.8K I = 8.23H

Classic 57 Alnico V ( " =6.5) 8.5K I = 4.45H

Classic 57 Plus Alnico V ( " =7.0) 13.8K I = 7.15H

 

So as you can see from this example..the alnico (or ceramic) type + DC resistance of the coil + the

coil inductance in Henries will give each unique p_up it's signature sound. The coil inductance

gives the p_up not only it's characteristic resonant frequency (in the 100hz to 6khz frequency

bandpass) but also a curve that shapes the individual p_up's response.

The insulation varnish thickness also makes some difference on the number

of turns around a standard bobbin and so on..

So, it's not all cut and dry in the magnet and coil winding sciences for pickups.

 

The inductance of the coil will also depend on the tension of the winder, and

the winding techique..tight winding vs scatter winding..and this makes a difference

as well.

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Carverman' date=' that's some amazing information.

 

Up until now, my knowledge could be contained in the statement, "magnetic pickups use magnets."[/quote']

 

Well up until recently, I took that also as a "given". However, Seth Lover's statement,

(in his interview with Seymour Duncan) mentions that the purpose of the magnet in a guitar pickup is to:

a) provide a steady state of magnetic flux around the coil

#-o magnetize the portion of the strings that are above the p_ups.

 

How the strings impart a combined and complex waveform by modifying the steady state of the coils magnetic

flux is still beyond me. Which now has me searching for information on how this happens exactly.

I'm still trying to find answers.

 

iE: Do the strings have 2 (or 3) magnetized sections directly above the 2 (or 3) pickups?

 

Are these magnetized section(s) additive (or subtractive) to the string's total magnetc strength?

(Assuming that both pickups have the magnet bars in the same polarity).

 

What happens to that same string when you flip the pickups around (change the position of the adjusting screws/poles in relation to where they were before)..

IE: the individual string adjusting screws (or poles) facing the nut or the bridge.

 

It's like a bag of potato chips..you just can't stop with one..the more you know about pickups, the

more you want to know how they work exactly.

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It's interesting that such a conceptually and electronically simple device can be so complex in its generation of sound.

 

But I'll leave the investigations to you. I'm happy enough just soldering Seymour Duncans into my guitars and basses (--ooops, and a Fishman in my Dobro).

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It's interesting that such a conceptually and electronically simple device can be so complex in its generation of sound.

 

But I'll leave the investigations to you. I'm happy enough just soldering Seymour Duncans into my guitars and basses (--ooops' date=' and a Fishman in my Dobro).[/quote']

 

OK, here's the physical proof that the guitar string becomes magnetized in specific areas

over the pickups.

 

I wanted to know if it was just the specific area over the string or along it's entire

length.

 

I read about steel wire recorders were used to record speech along a

length of fine round steel wire. These were used before magnetic tape was

discovered, of course..but the wire did hold onto some speech for playback

later, even if the fidelity wasn't there the same physics still apply.

 

Generally the easiest way to see things visually with a magnet is to use fine

grain iron filings small enough that even a weak magnet can attract them.

 

The guitar string is such a weak magnet or "magnets" if you want to be specific.

 

Once the guitar string becomes magnetized, the vibration of the string(s)

facilitates an induction into the coil, which is at constant flux - steady state flux

from the permanent magnet below the coil. (Or inside the coil, if the pickup

uses those round cylindrical magnets like the DeArmonds have).

 

Finding a bag of iron filings for the experiment isn't something you can

buy at your local h/w store..so I created enough for my test from filing

a soft iron bar with a mill file.

 

I marked the two areas of the bass E string with a black marker so that

I could dust that specific area with the iron filings and actually see the lines of force.

 

The magnetic forces seem to be concentrated only where the string and pickups co-incide.

Any other areas around the string did not seem to be affected to attract the iron filings.

 

The resultant photo is proof of what Seth Lover mentioned in his 1978

interview.

 

maglinesofforceonareasthatwereunder.jpg

 

The iron filings are more concentrated at the bridge humbucker string position because

the pickup was adjusted higher and the air gap between the string and pickup cover

was smaller than at the neck, magnetizing the string there at higher magnetic flux level.

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