Some pickup questions

Pickups, magnets, microphones, amps, speakers, cabs, whatever...
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Steve Sawyer
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Some pickup questions

Post by Steve Sawyer »

Let me say I've gotta get back in the shop. When I'm stuck not working with my hands I end up spending money on tools and materials, and endless hours doing research and learning...and driving folks nuts with questions!

Anyway, continuing my education re guitar pickups, there are a few things that are still puzzling me...

Polepieces/magnets - Magnets on single-coil pups are sometimes staggered to follow the radius of the strings (as they are on my MIM Strat). On some humbuckers, polepiece screws are presumably screws to allow similar adjustment of the distance between the polepieces and the strings, but the polepiece slugs are not. I also seldom actually see these screws adjusted above the top of the coil or pup cover, so I'm not sure if my assumption is correct. On the other hand, some pups don't expose the polepieces at all, and I've seen some humbuckers where both sets of polepieces are screws. Is there any logic to these variations, or are they simply a way of doing things a little differently to distinguish one product from another?

Also, there is much info around on the differences between Alnico 2, 5 and ceramic magnets, but nowhere have I gotten any indication that these types vary in the strength of the magnet (gauss) buy I'm guessing that's that's the functional difference. I've often wondered when charging the magnets, what effect it has on the tone when fiddling with the strength of the magnet, or whether a builder might go back and either slightly de-gauss or strengthen the charge of a pickup to modify the tone.

And finally - can't anyone discuss tone without relying on un-quantifiable and subjective terms like "bite", "warm", "muddy", "full", "sparkle" etc. etc. - I mean, we're not talking friggin' WINE here folks!! :D Doesn't it all boil down to frequency response? I so much appreciate comments about a particular guitar or pickups with reference to the frequencies emphasized. That at least conveys some meaningful information to me. Of course, I'm somewhat handicapped by being a bit "tone deaf". I listen to audio clips of different pickups and am often pretty hard-pressed to tell much of a difference between the examples. I can hear a difference, but it's so subtle that if I wasn't hearing them one-after-the-other I probably couldn't tell the difference at all! ;)

Thanks for any insight on any of the above...
==Steve==
Gordon Bellerose
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Re: Some pickup questions

Post by Gordon Bellerose »

Tone is such a subjective thing that it is almost impossible to accurately quantify.
The terms you mention are simply generic descriptors that almost everyone uses.

I aim for clean, full tones in my guitars. It is my opinion that clean is hard. It's easy to add dirt. :-)
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Steve Sawyer
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Re: Some pickup questions

Post by Steve Sawyer »

Gordon Bellerose wrote:Tone is such a subjective thing that it is almost impossible to accurately quantify.
The terms you mention are simply generic descriptors that almost everyone uses.
Yeah, I get the subjectivity and quantification thing. I'm willing to bet that two pickups with identical technical specs (what CAN be quantified) could have an entirely different tone. Still, it would seem that one could describe tone in terms of the frequency response - not in technical terms but in a way to allow comparisons between two different tones. A perfect example is "scooped" which clearly communicates (at least to me) that the high and low frequencies predominate and the mid-frequencies are suppressed.

The problem is probably that no-one has taken the time to put a "fat" (or any other) sound through an oscilloscope to 1) verify that everything that listeners agree is "fat" or "round" actually have similar frequency response patterns, and 2) determine exactly what those patterns are.

Might be an interesting little project - kinda like Pandora' Music Genome Project! :lol:

I guess part of my problem is that I'm somewhat isolated - I don't interact with any other musicians F2F so a I can't hear what someone means when they say "fat" or "full" or use any of those other terms. I'm left to my imagination as to what that means. I also have a limited stable (like two guitars) to play with, and they're both running single-coils, and one is a bass VI, the other a Strat, so not much there to experiment with! :)

===========

I also had a follow-up question re magnets.

One of my two electrics is a 25-year old MIM Strat. I understand that alnico magnets lose their charge over time, and I was wondering if one can restore the original sound to some extent by re-charging the pickups. I'm going to be doing some minor surgery on this guitar in the coming months, and I could easily re-magnetize the pups while I have it apart.
==Steve==
Bill Raymond
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Re: Some pickup questions

Post by Bill Raymond »

AlNiCo magnets "losing their magnetism over time" is subject of a lot of misunderstanding and "old wives' tales". If you were to do a little research you would find that AlNiCo can, in fact, be demagnetized by strong magnetic fields, but that otherwise it is fairly stable.
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Steve Sawyer
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Re: Some pickup questions

Post by Steve Sawyer »

Bill Raymond wrote:AlNiCo magnets "losing their magnetism over time" is subject of a lot of misunderstanding and "old wives' tales". If you were to do a little research you would find that AlNiCo can, in fact, be demagnetized by strong magnetic fields, but that otherwise it is fairly stable.
Thanks, Bill - like there is on virtually every other subject! :D

What I'd run across is a claim that one of the things that makes "vintage" pickups hard to duplicate is that their magnets have become weaker over time, contributing to their unique tone, plus claims that ceramic magnets don't share that tendency.

The Web is both a blessing and a curse - there is a lot of information out there, but you'll just as easily run across repeated erroneous information as you will the stuff that is true. Fortunately there are places like this forum that will cast doubt on some of the dodgy stuff so we can dig a little deeper - or do our own experimentation. Back to your point, yah - if you get out of the realm of the guitar "experts" and look at technical information from scientific and industrial resources, alnico magnets will lose their strength over time, but something along the lines of 3% over 10 years. This works out to a drop of about 15% over 50 years. Is that enough to have an affect on tone? I have no idea (see my questions above), but that information provides a basis for experimentation.
==Steve==
Gordon Bellerose
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Re: Some pickup questions

Post by Gordon Bellerose »

Don't forget that the tone produced by some older guitars is because the pickups were hand wound.
This method resulted in some guitars that sounded great, and lots that were real dogs.
A vintage instrument will not sound good just because it's old. This is another old wives tale.
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Peter Wilcox
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Re: Some pickup questions

Post by Peter Wilcox »

Interesting article on why pickups sound like they do: http://www.planetz.com/wp-content/uploa ... hnique.pdf

He's also written a book that goes into much more detail, but which doesn't seem to be currently available in the US in English: Electric Guitar - Sound Secrets and Technology by Helmuth Lemme
https://www.amazon.com/Electric-Guitar- ... op?ie=UTF8
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Steve Sawyer
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Re: Some pickup questions

Post by Steve Sawyer »

Thanks, Peter. That article looks great. I've been wondering about meaningful measurements that would provide some objective way of comparing pickups. Not making any gualitative judgements about their tone, but a quantitative analysis of how each achieves it's tone.
==Steve==
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Peter Wilcox
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Re: Some pickup questions

Post by Peter Wilcox »

Steve, here's an older article by Lemme that goes into a little more electronic detail http://www.buildyourguitar.com/resources/lemme/
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Jason Rodgers
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Re: Some pickup questions

Post by Jason Rodgers »

Gordon Bellerose wrote:Don't forget that the tone produced by some older guitars is because the pickups were hand wound.
This method resulted in some guitars that sounded great, and lots that were real dogs.
A vintage instrument will not sound good just because it's old. This is another old wives tale.
Depends on what vintage brand you're talking about, because if it's Gibson, then they were machine wound. And not to any predetermined DCR, but just until bobbins were full. This resulted in coils that were within a range, but not matched. Of course, this has played into the lore of "the" PAF, when it was mostly chance that produced the real gems. Same conclusion, though: some were great, some were dogs.
-Ruining perfectly good wood, one day at a time.
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Steve Sawyer
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Re: Some pickup questions

Post by Steve Sawyer »

Wow - really interesting stuff there, Peter.

That Pickup Analyzer that Lemme discusses would be a fascinating tool, as it can be used not only to objectively assess the characteristics of individual pickups, but also the entire system - pickup, strings, guitar, electronics & cable! It appears that he actually builds and sells a few of these per year, and my guess is that he would get somewhere close to $1000 for one of these based on some guy who was trying to unload his on eBay a few years ago. Hard to see an individual luthier, whether amateur or pro making this investment, but for those into making pickups for a living, it could be very useful - or for those high-end folks that custom-build guitars for individual artists. You could use that tool to dial-in the guitar by tweaking the system based on the customer's personal tonal preferences and the findings from the analyzer.

Lemme does sell his slick rotary-switch-cum-capacitor array that allows the guitarist to vary the tone capacitor. Might be worth investing in one of those just to do some experimentation (they run between about $50 and $70 or so depending on the exchange rate with Euros).

By the way, Lemme would appear to agree 100% with Jason and Gordon's comments above!! :D
==Steve==
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