Magnets really make a dramatic difference in pickups

[Elmore]

TM1 and El Gringo, thanks for the tip! I will look into this. Always chasing tone.

 

[marshall1987]

What is the consensus on the AlNiCo III magnets Gibson has been using on the latest Custom-Bucker pickups? Why did they decide to discontinue using AlNiCo II in their premier PAF style pickup?

 

[Garincha]

What is the consensus on the AlNiCo III magnets Gibson has been using on the latest Custom-Bucker pickups? Why did they decide to discontinue using AlNiCo II in their premier PAF style pickup?

I wonder about that either.

As I understand it, Alnico III is the rarerst used variant in original PAFs. It is said most of them were II and V, with an occasional IV once in a while. But III? I've always wondered why Gibson chooses the least representative magnet type.

Maybe Jon Gundry can chime in, as he knows more about that matter than anybody else.

 

[LtKojak]

As I understand it, Alnico III is the rarerst used variant in original PAFs.

A III was used in the period it was no Cobalt available because it was used to the production of arms and ammo used for WWII.
The 1st PAF p'ups came out in 1957, and at that time, Thomas & Skinner was Gibson's magnet supplier, and after old purchase docs found by Jon Gundry and Lindy Fralin, magnet bars were simply stated "Alnico". The A IV came from the conclusion of actual measurements with a Gaussmeter of fully-charged bars with a Zap charger.

So here are the facts.

Macht gut!

 

[marshall1987]

Jon Gundry at ThroBak has posted the following information about AlNi III magnets.

"A3 long / Very weak, nice clarity for use in P90 pickups but very low output for PAF pickups."

 

[jwalker]

You are most likely to see A3 in '52 and '53 era P-90 pickups. Some of these have a thicker magnet that is always A3 and sounds quite good in a P-90 but will not fit in a P.A.F.. I have seen 1/8" thick A3 in P.A.F. pickups but it is very unusual from my experience.

A2 and A4 have a similar inductance profile so it is hard to spot it without a BH curve. However I did get a copy of a 1940's era A4 BH curve so I'm quite sure it was manufactured and used by Gibson.

 

[thin sissy]

You are most likely to see A3 in '52 and '53 era P-90 pickups. Some of these have a thicker magnet that is always A3 and sounds quite good in a P-90 but will not fit in a P.A.F.. I have seen 1/8" thick A3 in P.A.F. pickups but it is very unusual from my experience.

A2 and A4 have a similar inductance profile so it is hard to spot it without a BH curve. However I did get a copy of a 1940's era A4 BH curve so I'm quite sure it was manufactured and used by Gibson.

jwalker, is there any consensus on magnets in P-90's throughout the 50's? Or could they be any kind during any year?

 

[Hamerfan]

Gibson ordered them in bulk and used whatever was delivered. Since 57 they used the same magnets for PAFs as for P90. This is the reason why those PAF junkies butchered lots of P90s to get a pair of "authentic PAF magnets" for their wannabe PAF clones.

https://www.pafhumbucker.com/paf-pickups-magnets.html

 

[matt173844]

Yes that is the consensus.

It could be the particular UOA5 I tried but afaic, the A5s stood in stark contrast to all the other magnets in that harmonic overtones really collapsed around the fundamental. There was a dryness and and a bitting crunch that I really liked at first until directly compare to a similar R9 with A3s when the lack of overtones was drastically apparent. I mean the difference was way bigger than a d18 vs a d28. I which I had a spectrum analyzer because I know what my ears heard.

A2s are juicy and round with and abundance of overtones that stand really in stark contrast to the UOA5.

The A4s to me sound closer to the A2s albeit with a touch less mids and a little more weight in the highs and lows. The less softness and compression gives it a woodier bite but without the loss of rich overtones.

Dude this is a great description of the UOA5 that I have. And your initial post is probably the best description that anyone has put to words regarding the feeling and sound from the different magnets.

Were you testing throbak magnets? If not, where did you get them?

 

[Offshore Angler]

Permanent magnets are permanent. Unless they are subjected to a very strong magnetic field they won't wear down. And the previous statement about how they were charged is spot-on.
The Br and remanence of the magnet depends on the blend, but the strength of the magnet depends of the charge.

There's also differences in how the magnets were sintered. Some are isotopically sintered and some are anisotropically sintered. This is when the magnets are sintered they are put in a strong magnetic field. This has the effect of aligning the magnetic domains and in layman's terms, makes them directional. So depending on which way they are sliced from the block they can have varying strength.

So , as in most things engineering-related, general statements are almost never all-inclusive and usually ill-advised.

As far as country of origin, almost all block comes from China. If the block gets cut into magnets here in the USA they are considered USA made, but still originated in China. Truth is, most Chinese magnets are higher quality than US magnets because they are manufactured in new, state-of-the are facilities, whereas magnets from the US can be from really old crap machines that don't hold tolerances on the antiquated slicers and grinders, in contrast to the new Chinese machinery and it's not uncommon for Chinese magnets to be EDM'ed.

Finally, almost all the rare earths used in magnets come from China, since the only other readily available sources of ore are from places that place them in the category of "Conflict Minerals".

And yes, I know a ton about magnet manufacturing and design, but that's another story for a different thread.

Chuck

 

[corpse]

Mr Wizard right there.
Good chit.

 

[corpse]

Ok back to learning.
I am a wire guy by trade. 44 years of wooden reels and molten polyethylene.
I used to discuss (read: listen to) Big Al and he worked closely with and was a disciple of Seymour Duncan.
Original PAF’s were wound with #42 enamel magnet wire- with like OA talks about- technology of the time shortcomings- that produced the wonderful results that we get in old PUP’s.
As there is only so much space on a bobbin, you can’t get too much more wire on there with #42 so they went to #43 which is pretty close electrically but there is room for more windings.
That’s me mostly just regurgitating. I get the science of it.
OK now to the smart people- what makes a PUP too bright or too dark? Well besides the listener. I am certain it’s on the LPF somewhere. It might even be in this thread- but some of you know.

 

[Mr. Papa]

I bought a set of 3rd Power MagFrag pickups that I’m planning to install this weekend if my pots order shows up in time. These have three magnets, A2 for the two high strings, A4 for the middle two, and A5 for the low pair. This takes the Duncan 5/2 idea a step further, so we’ll see how it turns out.

 

[matt173844]

I bought a set of 3rd Power MagFrag pickups that I’m planning to install this weekend if my pots order shows up in time. These have three magnets, A2 for the two high strings, A4 for the middle two, and A5 for the low pair. This takes the Duncan 5/2 idea a step further, so we’ll see how it turns out.

Interesting. Cool to see someone innovating in the space.