View Full Version : Nuby mistake with a neo
StarryNight
10-10-2008, 10:07 PM
Hello from Victoria, BC
I recently wound my first two humbuckers ordered from stewmac. I put both in my reissue Hagstrom. The neck sounds extremely good to me. The bridge also sounds great except for a weird volume drop on the low E string and the G string is very loud (actually the G string on the neck is also the loudest). My story has a slight twist though. Before winding the second p/up I decided to attach 4 3/4" neos to the long edges of the Alnico5 and left them there for about 15 minutes. after reading this forum for the last few days I realized that was probably not such a good idea. My question is should I try to degauss the magnet (how?) and recharge it properly? Could it have something to do with the volume inbalance or is there another reason?
Tony
SkinnyWire
10-12-2008, 02:07 AM
Hopefully, I'm not stating the obvious here but magnet charging or discharging is basically an instantaneous thing. So, 15 minutes or 15 nano-seconds has the same impact (e.g., no need to leave the NdFeB mags on for that long). If you want to use Neos for charging, consider building a vice like rig that you can find described here via the search function.
AlNiCo 5 is anisotropic, which basically means it has a "preferred" polarity. I'm not exactly sure what happens if you try to charge the magnet opposite that. I think it will hold the charge at a substantially weaker maximum than the preferred direction? I'll let one of the really smart people cover that.
In my experience, A5 is the most finicky grade - the most susceptible to "damage" due to stray fields and the grade I find most often wildly imbalanced across the face. Fully charging them generally helps to balance things out, but sometimes it's hopeless and you might have 300 G or more difference from one end to the other or weak spots in places. That's why I have them all over the house performing various tasks other than sourcing a pickup. You might want to try swapping in the neck magnet that seems to work fine for you or start with a fresh bar, etc.
Fresh strings and such too?
StarryNight
10-12-2008, 08:19 AM
No, you're not stating the obvious at all, very interesting stuff. A5 sounds very strange indeed. It sounds like by trying to switch the polarity, it will degauss but not flip. I'm not sure what polarity were the neo faces when I attached them so who knows what i did to the magnetic field. I'll definately be getting more A5s and do some testing. I guess it's all part of the learning process. the stewmac polarity tester is also on my short list. Thanks.
StarryNight
10-13-2008, 09:05 AM
Just an update. While the pickup was in the guitar I tried waving a stack (7 3/4") of neos over the pickup. What resulted was reverse of what I was getting previously i.e. the low and high strings were louder and the middle strings were barely audible. I did it again reversing the stack and all strings came up to volume. I kept experimenting waving the neos fast then slowly and reversing the stack a couple of times. I have no idea what i've done to the A5 but I eventually got all strings to sound relatively even. I'm curious if it will change at all after a few days. Definately having a strong magnetic field over the pickups changed the sound dramatically.
Possum
10-13-2008, 11:54 AM
What you did initially was charge one small section of the magnet more than the length beside it, at least if your neo is strong enough to do that. Actually alnico 5 can be charged lengthwise, I've done it despite its only supposed to charge in one direction, not sure whats up with that but you can. So you have a magnet edge than has uneven charges along its edge, they do anyway but you tweaked it in a screwy way really.
Waving neos over an assembled pickup is just going to scramble the charge and you won't get any kind of consistent result. What you are doing is messing up the magnetic circuit which consists of the pole screws, the keeper, magnet and slugs. All of these hold a charge when assembled, so it might be fun but will mess up your pickup and it will never sound like its supposed to. You may end up with south charge on one end and north in another section. You should disassemble the pickup and degauss all the parts, and charge the magnet the way its supposed to be if you want a pickup that works right.
I once actually reversed the polarity midway on a bar magent. It occured when I slid the a5 bar off of the neo bar lengthwise. I 'm not sure why it happened, but it was really odd.
If I recall correctly, I was never able to completely recharge it correctly afterwards either.
Possum
10-17-2008, 02:23 PM
I actually tried this on purpose once thinking I could make the pickup out of phase with itself, well it worked but the area where the polarity flipped had a dead zone there so D and G strings could hardly be heard......fun with science
Rosewood
10-17-2008, 06:55 PM
I've screwed up a bar magnet a few times and when viewed with a magnetic viewer the white line that's usually down the middle was closer to one edge and sort of notched.
LtKojak
10-17-2008, 09:38 PM
... without taking it out?
What happened to Possum sending a non-charged p'up to a customer made me think: if it happened the same thing to me with a humbucker, having a couple of powerful Neos from StewMac myself, how should it be done? Can somebody make a diagram or schematic to illustrate the operation?
Inquiring minds would like to know...
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