Pickup installation

[Danster]

Hey guys,
I bought a new pickup for my guitar. I thought I'd ask for some advice before I fry my guitar (or myself :D). The pickup is a humbucker. My old outgoing humbucker has only a single wire going to it from the guitar, but the new pickup has two wires. What to do?

[szulc]

The pickup has two coils with a magnet in the middle.
The two coils usually are wired in series out of phase (this is how they cancel the hum).
What does this mean? the coils are wound in a certain way say clockwise, lets call the wire on the out side of the coil the posiitive wire.
Out of phase means that one coil is connected in reverse of the other coil. Let's say the inside wire on one coil is connected to the inside wire of the other coil then the out side wires are connected to the ground and the signal. This configuration is call series : where one coil is connected in series with the other. Another way to connect them is in parallel which means each coils is connected to the ground at one end and the signal at the other.

An ohmmeter and a soldering iron/pencil would be useful.
Also some heat shrink tubing solder and flux or paste make sure to use rosin core wire and a low wattage soldering iron.
Both pickups should have a shielded wire to connect to the guitar switch or potentiometer. By shielded I mean having a braided metal sleeve this should be the ground wire (earth if you are european)
If you measure the impedence of the pickup from each of the two wires to the ground you should get two different impedences. from wire to wire should be yet a third value. THe most likely case is one wire is meant to be the hot/signal wire and the other is meant to be the tap meaning between the two coils where they are connected together. So from shield to one of the wires should be twicw the impedence of from the shield to the other wire.

The wire with the highest impedence from the shield is your hot/signal wire connect it to the same place as the hot wire from the old pickup ( not the shield) the shield should then be connected to the can of one of the pots or a ground point on the switch or jack ( wherever the old shield was connected) if you just tape up the unused wire this will work fine, but you could use this additional wire to tap your pickup coil turning it into a single coil to get a more strat like tone ( and hum!), just add a switch and connect this wire to it and the other end of the switch to ground, when the switch is on you will have a tapped coil, when it is off you will have a humbucker.

Good luck

[Danster]

Dude, I believed you before when you said you were an engineer. You didn't have to post all of that to prove it! :D

I know the terms parallel and series, but I don't really get the theory behind "out-of-phase". I suppose its kinda like two light or sound waves cancelling each other if the trough of one is aligned with the crest of the other? (Be gentle, it took me three tries to make it through first semester college physics :().

If you measure the impedence of the pickup from each of the two wires to the ground you should get two different impedences. from wire to wire should be yet a third value. THe most likely case is one wire is meant to be the hot/signal wire and the other is meant to be the tap meaning between the two coils where they are connected together. So from shield to one of the wires should be twicw the impedence of from the shield to the other wire. I was about to say that neither the new nor the old pickup had any measurable conductivity between the other wires and the ground, but then I realized that when I was trying to measure this (last night), I had my ohm meter set at the lowest range, and so I was probably just out of range on the meter. Dang it, I didn't think of that (it was past my bedtime when I was messin' with it).

The wire with the highest impedence from the shield is your hot/signal wire connect it to the same place as the hot wire from the old pickup ( not the shield) the shield should then be connected to the can of one of the pots or a ground point on the switch or jack ( wherever the old shield was connected) if you just tape up the unused wire this will work fine, but you could use this additional wire to tap your pickup coil turning it into a single coil to get a more strat like tone ( and hum!), just add a switch and connect this wire to it and the other end of the switch to ground, when the switch is on you will have a tapped coil, when it is off you will have a humbucker.That sounds cool! I put the guitar back together already with the new humbucker. Since I couldn't measure the conductance (and not being a real patient person), I just picked a wire, and hooked it up. After pausing while contemplating whether or not everything was gonna blow, I turned everything on, and voila, everything actually worked! I didn't want to get too ambitious with the electronics, as I wanted to first get things working. I like your idea about the second wire and the switch though. I might try that next time I start digging around in there. Thanks James! (BTW, the new pickup sounds great; its an Ibanez AH2).

[szulc]

Is it acting like a humbucker or a single coil?
You had a 50% chance of gettig it right.
You can get pots that have a switch inside so when you pull up on the knob the switch will activate, that way you don't need to drill extra holes in your guitar.Dude, I believed you before when you said you were an engineer. You didn't have to post all of that to prove it!
Not trying to show off here just trying to make sure the idea was coming through , since I had no idea of your knowledge level, I needed to be precise.I know the terms parallel and series, but I don't really get the theory behind "out-of-phase". I suppose its kinda like two light or sound waves cancelling each other if the trough of one is aligned with the crest of the other? Each coil has a waveform that it gets from the string and from the ambient noise (60Hz or 50Hz hum), by connecting them in series but with one coil reversed the hum is cancelled(as well as the parts of the string signal that exactly match in phase and amplititude), but the difference between the signals from the strings are amplified, that is why humbuckers lose hi and low definition but gain all the midrange. The signals to each coil are slightly different because the coils are in different places along the string, the phase will be different and the amplititude is different.

[Danster]

Originally posted by szulc Is it acting like a humbucker or a single coil?
You had a 50% chance of gettig it right.I think its acting like a humbucker. I am pretty green when it comes to identifying the sounds of various pickup types and positions, and I don't own a guitar with a single coil at the bridge position, so I don't have a real firm idea of what that sound would be. But, with the gain turned up, it sounds pretty rock-n-rolly!

You can get pots that have a switch inside so when you pull up on the knob the switch will activate, that way you don't need to drill extra holes in your guitar.I was wondering about how I would go about installing such a switch, so that makes it easy. I like the idea of being able to switch that pickup between humbucker and single coil. Put on your engineer hat again and answer me a question if you will. With the switch set to that tap wire, it seems to me that you have just put that second coil of the humbucker in a parallel circuit with the tap wire (while in series with the "first" coil). Is it so that that second coil has power to it, but the relatively high resistance just causes most of the current to flow through the tap wire, so that the second coil basically does not influence the sound?
Not trying to show off here just trying to make sure the idea was coming through , since I had no idea of your knowledge level, I needed to be precise.Just messin' with ya dude... I appreciate all your input to this forum, whether musical or otherwise. Each coil has a waveform that it gets from the string and from the ambient noise (60Hz or 50Hz hum), by connecting them in series but with one coil reversed the hum is cancelled(as well as the parts of the string signal that exactly match in phase and amplititude), but the difference between the signals from the strings are amplified, that is why humbuckers lose hi and low definition but gain all the midrange. The signals to each coil are slightly different because the coils are in different places along the string, the phase will be different and the amplititude is different. OK, I'll have to study this later when I have more time. I hadn't heard that before about the strong midrange signal from humbuckers. Is that why rockers often crank up the low and high amp settings and leave out the midrange?

[szulc]

With the switch set to that tap wire, it seems to me that you have just put that second coil of the humbucker in a parallel circuit with the tap wire (while in series with the "first" coil). Is it so that that second coil has power to it, but the relatively high resistance just causes most of the current to flow through the tap wire, so that the second coil basically does not influence the sound?
The tap is GROUNDED so the second coil is out of the picture completely.I was wondering about how I would go about installing such a switch, so that makes it easy. Connect the coil tap to one side and the other to ground. (It doesn't get much easier than that.)