Awesome answering machine message today

[WolfeMacleod]

So I did some pickups for this dude a couple weeks back. Something I'd never done before...an experimental set of 3 P-90's. Each with an Alnico 2 and a Ceramic. Never done it before, but thought I'd give it a shot.
Sent them out so they could get his guitar back together...and waited patienty for a report. Patiently. White knuckled.

Got a call today. I was out picking something up. Bummed that I missed the call, but I managed to get ahold of him a bit later.
here's the message

So anyways, after talking to him, it seems he's going to be discussing with the company about having these pickups put in his signature model guitar. As well as....maybe making this pickup a signature model pickup!

[Mystic]

Hope that works out for you.

[soundmasterg]

Hey thats cool Wolfe! Maybe a ticket to the bigtime where Jason lives is in order?

Greg

[SK66]

Wolf, that's pretty cool. I really like Rick. Anyways, I hope I'm misunderstanding something here as it seems you may have made a mistake I wouldn't expect of you.
If you place a ceramic in close proximity to Alnico in opposition it will progressively degrade the alnico over time. I tested this with a similar setup and noted a measurable loss of gauss over a period of 2 months although no significant loss immediately after assembly with a 3/16" gap between magnets; that was with C8/A5 bars.
I was once told by a magnet manufacturer you shouldn't use alnico and ceramics in the same assembly (not product specific) at all...I break that "rule" myself, but in my case the magnets are seperated slightly and attracting.

[WolfeMacleod]

Wolf, that's pretty cool. I really like Rick. Anyways, I hope I'm misunderstanding something here as it seems you may have made a mistake I wouldn't expect of you.

Eh...I just did what he wanted me to do. That is something I'll look further into though.

[madialex]

yup

Wolf, that's pretty cool. I really like Rick. Anyways, I hope I'm misunderstanding something here as it seems you may have made a mistake I wouldn't expect of you.
If you place a ceramic in close proximity to Alnico in opposition it will progressively degrade the alnico over time. I tested this with a similar setup and noted a measurable loss of gauss over a period of 2 months although no significant loss immediately after assembly with a 3/16" gap between magnets; that was with C8/A5 bars.
I was once told by a magnet manufacturer you shouldn't use alnico and ceramics in the same assembly (not product specific) at all...I break that "rule" myself, but in my case the magnets are seperated slightly and attracting.

Good catch SK. I wouldn't have thought about it either, specially if Rick Derringer called me in person He mentioned being a little bright up high, maybe they will degauss to the sweet point and he will be extra happy.

[WolfeMacleod]

SK, I spoke to a couple people at my magnet suppliers, and they've told the the knockdown of Alnico 2 will be almost immediate, but won't get any worse over time. Nothing to worry about. Although I will speak to Seymour about it and see what he says, as well.

BY the way, what's been going on whit'choo lately? Been a long time man, hope you're doing well!

[David Schwab]

Very cool! Derringer is one of my faves too.

[Possum]

Derringer

I messed with using different alnicos in a test set up only measuring with the meter, you can get results you can't get any other way, but I found only one combination that had the most noticeable effect. I would think that you're probably right in thinking that the A2 will only degrade the same as if you had repeatedly pushed the two magnets together a bunch of times, so all you really need to do, is do that up front before you send them, also you'll be able to see how down it will go. I did a bunch of Derringer's album packages for Shrapnel over the years, wish he would do another album with us, one of the better blues guys they have done, we do Leslie West but he's a very simple player.......

[Zhangliqun]

I had heard that you get kind of a dominatrix relationship between to magnets in P90's anyway, even if they're the same Alnico grade. One stays strong and the other weakens a bit.

I set up my P90's so that one is full-strength and the other slightly degaussed so that the side of the poles I want to be stronger is set in advance.

[Possum]

huh?

did you actually measure stronger gauss on one side of the poles? I would think all that flux would mush together

[David Schwab]

I guess I could see how from one side of the poles to the magnet return path would be weaker... so it's seeing more of the string on the stronger side of the pickup.

Jazz guitarist Attila Zoller got a patent (3588311) on a pickup in 1971 that has an asymmetrical flux field. He has a three magnets arraigned so that the left one is south up, the middle is north up and the right one is laying on its side so north is facing the inside of the coil. This produces a field (he calls it a "bidirectional flux pattern") that extends off to the right more and presumably picks up more of the up and down motion of the string, which is the way acoustic guitars function.



Bartolini's two patents are also about having a flux pattern that picks up the strings in an asymmetrical manner. This is why the old Barts were called Hi-A (high asymmetry). Bill Bartolini also states that having round pole pieces gives that "plucky" sound because they pick up the horizontal and vertical movement equally, and he actually used flat trapezoidal and rectangular poles.



It's all quite interesting, and mind numbing too! Shows how important the magnetic circuit is, beyond just the type and size of the magnet!

[Possum]

patent numbers?

do you have the patent numbers for these, very interesting stuff....

[ken]

Ohh, my head....

I've been studying this post, it's fascinating. How would Rickenbacker's horseshoe magnet pickups work magnetically - what shape of flux field would they have? Or Fender's original 1940's steel pickups?

Ken

[David Schwab]

do you have the patent numbers for these, very interesting stuff....

Attila Zoller: 3588311

Bartolini: 3983777, 3983778

Yeah, it's fascinating stuff. The two Bartolini patents are quite detailed and technical. I bought one of the early Bart Hi-A pickups when they first came out. Great pickups, and from reading his patents, he really knows what he's talking about!