Do passive pickups become weak, and die, over time?

meev992 · #1 08-05-2007, 09:36 PM

I finally got a second bass, i'm loving it

I might be thinking way too far ahead into the future; but just out of curiosity, will the pickups on my bass become noticeably weaker during my lifetime?

I tried searching but i couldn't find anything that really answerd my question.

weefdog · #2 08-05-2007, 10:03 PM

Over time the magnets themselves will get weaker, but its the difference between a 58 strat and a new strat. Weaker magnets have lower sensitivity to the strings, and a more mellow tone. But if that broken-in tone is not agreeable to you then worry about it in 20 years. Thats about how long it will take to make a difference in the sound. Don't forget that you can raise the pickups closer to the strings. Like an acoustic guitar, all electric guitars take a long time to start working together as one. In the hundreds of guitars that I have built over the years, I have never been able to duplicate the exact sound over and over. Every part is different! If you found a bass with the sound you love, then just play the dang thing and be happy.

Rattman · #3 08-06-2007, 01:26 AM

-I've never heard this issue come up before on TB...

.. But when I first started playing in the '70's, pros & semi-pros at that time were having a fairly easy time of buying instruments made in the '50s. Anyway, one of the issues I heard time and time again was that players INSISTED that the original PUPS were 'shot' and needed to be 'rewound'. Yes, they believed that somehow the enamel copper wire that wraps around the permanent magnet, had by some unknown process of time and age had worn out!

But heres the 'rub'.. after these pros had taken these extremely valuable Gibsons and Fenders apart, and had the PUPS rewound with 'modern'.. either thicker or thinner gauge wire.. But they "hated" the new tone! My first instinct upon hearing these stories was "why didn't they just live with it"? Unbelievable and so sad to see those irreplaceable resources scaundered that way... the '70s was pure excess.

meev992 · #4 08-06-2007, 02:30 AM

Quote:

Originally Posted by Rattman

-I've never heard this issue come up before on TB...

.. But when I first started playing in the '70's, pros & semi-pros at that time were having a fairly easy time of buying instruments made in the '50s. Anyway, one of the issues I heard time and time again was that players INSISTED that the original PUPS were 'shot' and needed to be 'rewound'. Yes, they believed that somehow the enamel copper wire that wraps around the permanent magnet, had by some unknown process of time and age had worn out!

But heres the 'rub'.. after these pros had taken these extremely valuable Gibsons and Fenders apart, and had the PUPS rewound with 'modern'.. either thicker or thinner gauge wire.. But they "hated" the new tone! My first instinct upon hearing these stories was "why didn't they just live with it"? Unbelievable and so sad to see those irreplaceable resources scaundered that way... the '70s was pure excess.

indeed, long time poster/lurker, but i'm on a new account. I tried searching, but i didn't find anything/ ever heard anyone talk about this. I'm just really anal-retentive about the conditions of my basses/guitars and I was just wondering if they'll be more or less the same when i'm, maybe, 80 years old

and has been said previously, yes, now that i think of it, perhaps it's not such a bad thing if they "weaken" although, from my new understanding, not much weakening happens over time.

I just like to keep all of my insturments as fresh and new as the day i first got them

thanks everyone.

Searcy · #5 08-06-2007, 06:49 AM

Some old Fender pickups die because they didn't insulate the magnets from the wire. This is a short and can be measured with a meter. But magnets lose their power at a rate of about 2% every 100 years as has been pointed out. I wouldn't worry about it.

OrionManMatt · #6 08-06-2007, 08:52 AM

Quote:

Originally Posted by GlennW

From S. K.'s website:

"Magnet age: Some say alnico weakens with age, and this relates to magnet strength as previously explained. (Magnet manufacturers claim a loss of strength at a rate of aprox .2-2% / 100yrs) However, some manufacturers are "aging" magnets by heating. I have found through testing that this type of "aging" does NOT weaken the magnet (there is a point at which it will, but it's almost an "all or none" situation) What it does do is "temper" the magnet (alnico) relieving internal stresses. My testing has shown that before tempering there was often an unevenness of strength between magnets of the same "rating", i.e.alnico5, even between the two poles of the same magnet. The tempering almost always equalized the strength of the two poles of the same magnet, and lessend the variance between magnets of the same rating. However, it was not uncommon to still find some variance (I believe significant). For this reason I now temper all alnico magnets and test them for strength. As a side note, information provided by a magnet manufacturer indicated that tempering in this manner will make the magnet less susceptible to outside interference."

S.K. ?

bkief1 · #7 08-06-2007, 09:17 AM

Do passive pickups become weak and die over time...yes, they can.

Why? Not because of magnets losing strength.

For this example, let's assume the pickup owner has not tried to "play around" with the pickup. In a pickup, the coil wire is covered with an insulating material. As the wire ages, some cracking of the insulation occurs and a few shorts develop. If the cracking is significant, the increased frequency of the shorts can result in a weaker or dead pickup. If you were to examine the specifications for 42 AWG wire used by most, but not all manufacturers for winding pickups, the thickness of the wire and insulation can vary by quite a few thousandths of an inch and still be labeled as "acceptable". If your pickup has some thinner insulation, and etc....well, you get the point.

HTH

metalmariachi · #8 08-06-2007, 01:35 PM

+1 Bkief1 & Glenn.
That pretty much covers it. The cracking helped along by vibration eventually causes shorts. In other cases the coils can open if there is a loose spot in the windings where vibration can cause the wire to break.
It just happened to my ’70 Jazz, the sound kept getting weaker and weaker until there was nothing.
So it could happen, but there are many ‘50s Guitars and basses out there still going strong with the original pickups.
If you want to play it safe, just figure out who the ultimate rewinder is and keep his number handy.

MM