hugh
Meter Reader 1st Class
Posts: 50
Likes: 0
|
Post by hugh on Jul 7, 2007 11:27:51 GMT -5
Here's the diagram I made of the stock Squier '51 humbucker bridge pickup internal wiring. It has a three conductor connection to the controls. Red is the coil split wire, white is the hot, and black is the ground. I attempted reversing the polarity of the whole thing to make it humbuck in single coil mode with a Seymour Duncan Vintage Tele neck pickup. That didn't work. I had to reverse the polarity of the neck pickup, and now it humbucks in normal mode in the middle position. When I pull the coil split it selects the north coil on the humbucker... which apparently is the wrong wind/polarity to humbuck with the Tele neck pickup. I've tried flipping the humbucker around completely and reversing polarities... but then realized I'm wasting my time because when its flipped the other way, the wind is flipped too. To fix this problem, I want to select the south (closer to bridge) coil in split mode but retain the original polarity. This means I will have to change the order of the two coils in series inside the humbucker. Here's a diagram I came up with: What effect will this have? Will the humbucker still work in normal mode if I select only that pickup? Do you think it will then humbuck in the middle position with the south coil selected? I've also considered removing the coils and physically switching them, to swap the winds. (one should be wound in the opposite direction, right?) If I did this, I would retain the stock wiring, I think. Thoughts?
|
|
hugh
Meter Reader 1st Class
Posts: 50
Likes: 0
|
Post by hugh on Jul 7, 2007 13:47:03 GMT -5
Well in my impatience, I went ahead and tried it.
It does appear to work as expected.
The one thing it made pretty apparent now, though, is the poor tone of the stock humbucker VS the Seymour Duncan Vintage Tele neck pickup. I had to lower the neck a little so it wouldn't completely overpower the bridge... and switching back and forth now, I've realized it may be time for a JB or something in the bridge. I used to like the stock humbucker, but now not so much.
I would still love to see some comments on whats going on with the way I wired it, why it does what it does, etc...
I guess the series order of the coils doesn't make a difference in hum canceling. However it may have a negative effect on tone.
|
|
|
Post by JohnH on Jul 7, 2007 15:27:31 GMT -5
Hi hugh - welcome to GN2. Yes you got that right, so well done. If you can sucessfully re-phase a humbucker on your first post, then you are more than welcome here!
Presumably in its original state, you had the sounds of the two pickups in phase, ie it was a full deep combo sound rather than a thin one. Because thats the other thing that goes wrong with phasing of coils, particularly when combining two different types.
But given that, you kept the signal phase directions intact, but just swapped the series order of the two Hb coils, so that when one is shunted to get the single coil sound, it is now the south coil that remains active instead of the north coil. This swapping has no effect on the basic tone of the humbucker, nor its ability to be humcancelling with itself.
With the four wires from the humbucker all available, it is possible to sort out most phase and humcancelling problems with other pups just by selecting those wires, you dont need to get inside the pup. It also doesn't help the electrical phasing to spin the pup around physically. The reason to do that would be if you want to choose the physical position of the selected coil. For example, in a bridge Hb, I like my single-coil option to be the one nearer the neck.
If however, you want to select optimum phase, humcancelling and you want to specificaly choose, say, the adjustable coil to be the single-coil, then thats one more variable, and if youre unlucky, then sometimes it needs another step of getting inside and reversing the magnet, on one pickup or the other.
cheers
John
|
|
hugh
Meter Reader 1st Class
Posts: 50
Likes: 0
|
Post by hugh on Jul 7, 2007 18:31:01 GMT -5
Thanks for the welcome. I'm so happy to find a forum with this much electronics info and knowledge floating around. Most guitar forums/sites I've been on use a lot more guesswork for the electronics and less theory. I've been an electronics technician for years... so the theory interests me. Back to the pickup: So I'm thinking now that routing the signal through the south coil and then the north coil might have taken some of the brightness and bite out of the original tone. I think that is why I don't like this humbucker anymore.. it just doesn't sound like it used to. It does sound good in single coil, albeit a little weak. In humbucker mode it just isn't the same. I was also thinking about hum canceling theory and how placing the two single coils closer together is supposed to strengthen the effect, right? Maybe this is why they used the north coil in the first place... and most likely a RW/RP neck pickup. (obviously, because when I pulled it, the new pickup hummed away) So here comes the next big question: How can I move the current phasing into the north position and retain hum canceling in single coil mode, middle selector position? Can I physically swap the coils and retain current wiring? Should I flip the magnet and put the wiring back the way it was? My guess is the winding of the south coil is what I need in the north position, but I don't really know. Oh, and none of the poles are adjustable. This is a really cheap pickup... and I'm not afraid to break it. I've got a spare, even. EDIT: I just had a chance to sit down and really play it... and realized its now out of phase in the middle position. All the bass cuts, as expected. What to do now?
|
|
|
Post by JohnH on Jul 7, 2007 20:26:24 GMT -5
Ok So, neck pickup on its own is fine? Hb on its own is in phaseand humcancelling? Bridge single and neck together are humcanceling but sound thin? Bridge Hb and neck Sc also sound thin (and presumably not quite humcancelling).
If all the above is yes, then, relative to your second diagram, swap the two black wires, leaving the two whites connected to red. That will reverse the phase, go back to the other Sc coil, but this time it will be correct phase and hum.
probably
well, possibly
John
|
|
|
Post by ChrisK on Jul 7, 2007 23:28:03 GMT -5
There are three components to the phasing of a pickup.
1. The instantaneous direction of string vibration.
2. The magnetic polarity of the pickup
3. The winding direction.
You have to change any two of them to effect a change in the hum sensing phase (in conjunction with another coil) without changing the signal sensing phase.
A humbucking pickup is one where the hum sensing phases cancel, but the signal sensing phases do not. Common mode hum vs differential mode signal.
Phase is only relative as a relationship to another coil.
If you want to maintain the same phase relationship with another coil, you must swap the coil lead wires as it connects to the switching circuit AND reverse the magnetic polarity. This is nigh impossible with Fender type single coil pickups, but relative easy on side-by-side coil humbuckers.
First and foremost, get or make a magnet polarity tester. I have one that I used to make several others (only one reference is needed). And again, magnet polarity, like wiring phase, is only relative to another pickup.
Number 1 above is impossible to change.
Number 2 is impossible to easy to change depending on the pickup type.
Number 3 is trivial to change (just swap the coil lead wires as they connect to your circuit).
|
|
hugh
Meter Reader 1st Class
Posts: 50
Likes: 0
|
Post by hugh on Jul 8, 2007 13:07:44 GMT -5
OK I will make a polarity tester. In the meantime, questions:
Winding direction: I thought this was a physical aspect, and not electrical. If the winding is wrapped in a clockwise motion vs counterclockwise... then these would be opposite windings, right? I know you can switch the electric polarity of the circuit by switching wires, but this will not change the winding direction as they are related to each other, right?
If I spin the humbucker around now, it will swap polarity, and phase, but keep the same winding directions. It will stop hum canceling, but put it back in phase so it would sound right again?
So by this theory, I need to flip the magnet and keep everything else the same. I think.
Should it still cancel hum if I flip magnetic polarity now?
I'm sorry I'm throwing all these questions at you guys, but I would really like to understand how these pickups work. I don't want to take the short answer and make it work... only to have to ask you again next time I do this. Thanks a lot for the replies.
EDIT: I spun the magnet in the humbucker 180 degrees. I didn't even have to de-solder the wires to do this, so I stuck with the wiring diagram #2 above (my rewire)
I put the strings back on and tuned it up... and to my surprise - It sounds fantastic! The single coil humbucking works as I want it to, and the sound in the middle position is just great.
I really got to thinking now, could I have solved this whole problem by flipping the magnet in the first place? Would the stock wiring do the trick?
Like I said before, the humbucker just doesn't sound as good with the south coil in front of the north coil in series. When in the bridge position now, the humbucker still doesn't shine like it used to. Looks like I've got one more experiment to try.
|
|
|
Post by ChrisK on Jul 8, 2007 23:34:32 GMT -5
That'll be $1 U.S.
Same thing.
Yep.
Yep.
As who are related to each other? The other coil for sure.
It WILL change the relative phase of the signal.
To effect a humbucking circuit, the coils must have the same signal phase (or the string signal will mostly cancel) and opposite EMF sensing phase (so the EMF signal WILL mostly cancel).
This generally means that the coils must have windings in two different directions (for EMF cancellation) and magnets of two different polarities (for the string signal to not cancel out). Having the two different winding directions (using top coming vs bottom going vs south start vs north to Alaska (I know, I used to live there a'way up North) rattlesnake (oil) boutique side-winding pickup salesmen or just swapping the coil leads for those of us constrained to the actual laws of physics in a 3 dimensional plus time variable universe), effects that there hum cancellation which we compensate for by employing magnets of both polarities (changing the effective winding direction and the magnet polarity in said coil is changing two of those aforementioned three things required to keep the sensed string signal the same).
I will edit the list of the three things:
There are three components to the phasing of a pickup.
1. The instantaneous direction of string vibration.
2. The magnetic polarity of the pickup COIL MAGNET
3. The EFFECTIVE winding direction.
|
|
hugh
Meter Reader 1st Class
Posts: 50
Likes: 0
|
Post by hugh on Jul 9, 2007 6:53:38 GMT -5
Alright, so it doesn't matter which way the pickup is wound, by what you're saying? We can just swap the leads and it will switch EMF phase.
Does this mean if we have two identical single coils, we could turn one 180 degrees, wire it in series with the other, and it would be a humbucker? I'm also assuming the flipped coil would be wired backwards as well.
If you don't need a reverse wound coil, then why do pickup companies mention reverse wound/reverse phase? Couldn't they just flip the magnet? Or are they just changing the colors of the leads so positive and negative are the 'right' colors?
Chris, You made me scratch my head a little after reading your last post... but I finally understand a few more things. The reversed poles of the magnet cause the strings to push the sound wave in the opposite direction, while the coil is working in the opposite phase. Since the coil picks up the opposite phase, the reversed phase of the energy created by string movement comes through in the same phase as the opposite magnetically phased coil.
However, EMF is not generated by string movement. Therefore it only effects the two idle coils and they are out of electrical phase, canceling the wave out.
Again, this leaves me wondering, whats the big deal with reverse wound coils, then... such as the middle coil of a Strat set? Just output lead color?
This little experiment has turned out to teach me a lot more than I had expected. Thanks again!
|
|
|
Post by JohnH on Jul 9, 2007 7:08:43 GMT -5
Just an example, but with a normal single coil, you can turn it into RWRP but flipping the magnet and reversing the leads. Reversing the connections tothe leads reverses the hum, so it will then cancel hum with another pup, but is also reverses the sound. Flipping the magnet reverses the sound again, putting it back where it started, and does not affect the hum so it stays reversed.
John
|
|
|
Post by wolf on Jul 9, 2007 15:39:42 GMT -5
HughOn my website, I have a page that discusses humbucking pickups www.1728.com/guitar1a.htmIt's not the greatest explanation but the illustrations and the text are very straightforward. I have a feeling that the magnets in your humbucker might still be causing you some problems. Just read the top half of that page. (It was written to show how a 2 wire humbucker can be changed to a 4 wire humbucker).
|
|
hugh
Meter Reader 1st Class
Posts: 50
Likes: 0
|
Post by hugh on Jul 9, 2007 17:25:19 GMT -5
Yup, you just confirmed what I figured out through ChrisK's post and all the other stuff I've been reading and the experimenting I have done with these cheap humbuckers.
The misnomer of "reverse wound" is what through me. It's just swapping the leads. I thought they were actually winding the coils in opposite directions. (one clockwise, one counter-clockwise)
I've got it working great now. It cancels hum perfectly in the middle position with the coil split on, and the humbucker works normally by itself as well.
This is my first project that retains a single coil in it, I've always swapped them out for humbuckers. (even my Strat with three Seymour Duncans in it) I now understand why you can't cancel all the hum when you use a humbucker in conjunction with a single coil. The single is adding to the EMF wavelength in only one phase, while the humbucker is killing the EMF between its two coils.
What I have now is hum in the neck and middle, silent on the bridge. With the humbucker coil split it hums in neck and bridge, but the middle is silent. This is the best I can hope for.
|
|
|
Post by ChrisK on Jul 9, 2007 19:01:36 GMT -5
Define 180 degrees (as in which way). If we just rotate it so that the pole originally under the high "E" string is now under the low "E" string and the pole originally under the low "E" string is now under the high "E" string, no. The wire winding still goes in the same direction.
If we flip the pickup over so that on a single coil Fender type pickup the bottoms of the pole magnets are now the tops of the poles next to the strings, yes. Because we have reversed the winding direction (we're still using the exact same lead wire connections as well) AND we have reversed the pole magnetic polarity (that there any two of the three things).
It's not a misnomer, folk had/have done it by winding in the opposite direction. However, with the normal tolerances on wire tension and attention paid to the actual number of turns wound, reversing the leads works just as well (and is a whole bunch cheaper in production volumes - only gots to make one coil type and twice as many - volume rules).
|
|
hugh
Meter Reader 1st Class
Posts: 50
Likes: 0
|
Post by hugh on Jul 9, 2007 20:38:47 GMT -5
I meant example A, spinning the low E to the high E and keeping it face up... then switching the leads around.
That would change the magnet direction, right? And switching the leads should be the other step needed, right?
Or is there something more confusing about the single coil pickup's magnet that you're not reversing it by spinning it 180? (again, right side up)
|
|
|
Post by JohnH on Jul 9, 2007 21:45:16 GMT -5
Spinning a pup end to end does not change its phase or hum direction. The magnet poles on most single coils face up and down rather than end to end.
John
|
|
hugh
Meter Reader 1st Class
Posts: 50
Likes: 0
|
Post by hugh on Jul 9, 2007 23:22:02 GMT -5
Gotcha, I just tested a couple single coils and figured that out.
So to flip them, I'd have to rip the magnets off the back and flip them upside down.
|
|
|
Post by wolf on Jul 9, 2007 23:43:05 GMT -5
John HI agree about the polarization of pickup magnets. As my illustration shows on that page: www.1728.com/guitar1a.htmthe pickup magnets are polarized along the edges as opposed to the ends. You can't think of them like those "grade school" magnets that were polarized on the ends like this N----------------------S
|
|
hugh
Meter Reader 1st Class
Posts: 50
Likes: 0
|
Post by hugh on Jul 10, 2007 0:12:50 GMT -5
He means up - as in pointing outward towards the strings.
|
|
|
Post by ChrisK on Jul 10, 2007 11:53:28 GMT -5
I guess that we've expended more than enough kiloWords (kW) on this topic. Maybe a picture is in order. Here's the original side by side coil pickup patent from Mr. Seth Lover (and aboot a few others to boot): www.google.com/patents?id=wxoCAAAAEBAJ&dq=2896491
|
|
hugh
Meter Reader 1st Class
Posts: 50
Likes: 0
|
Post by hugh on Jul 10, 2007 17:31:23 GMT -5
Again, I would just like to thank you guys for a warm welcome here and a wealth of knowledge.
|
|