Can you make alnico bar magnets with different strenghts??

[5F6-A]

????????
using the same type of alnico that is.
me wonders....

[Jaicen_Solo]

Yes it is certainly possible!

The actual magnetic flux (strength) of a given grade of alnico can be anything from almost 0 (ie, the same as the earth's field around it), to (somewhat less than )whatever the theoretical max flux is. You can therefore 'charge' an alnico magnet to the desired strength.
I believe this is partly responsible for the 'mojo' certain vintage pickups have, as their alnico magnets have lost charge over time, becoming softer and more dynamic. Certain boutique manufacturers in the US have picked up on this and are advertising, 'aged' magnets  :roll:
Much of the perceived differences in tonality between different grades of alnico are related to the different alloys of which they are composed.
These all affect the inductance and frequency response differently.

[Steve-Mr Pig 2U]

Yes you can, but only alnico magnets. Some of ours use magnets that aren't saturated fully, but we dont "age" magnets.

[HTH AMPS]

isn't the amount of charge of magnet looses in our lifetimes almost negligible?

 :twisted:

[Ratrod]

isn't the amount of charge of magnet looses in our lifetimes almost negligible?

 :twisted:

I heard or read about that somewhere. I believe it'll take 100 years or so before the magnet loses any significant power.

[MDV]

*Science lesson alert*

Magnetic materials have a property called coercivity which is different from one to another. Some have low values and last millenia, some, paticularly early metal composites like alnico, have high coercivity

*Science lesson over*

I recon it takes a couple of decades minimum.

Edit: I think I puzzled it out: when a magnetic material moves in a magnetic feild the magnetic field does work on it (as it is if its totally stationary, but more slowly). If the field is doing work energy must be conserved and the feild must diminish in energy (inductance). Soooooooo strange as it may seem old pickups could be much weaker than you expect of their age because theyve been in a guitar pulling strings around the place, which has lowered the output of the pickup. The more played a pickup, the weaker and more 'aged' it sounds (I think).