Reverse Polarity, RWRP Question

[tzoranski]

Ok, I'm kinda new to the whole wiring thing. I've downloaded this diagram from
jemsite (http://img15.imageshack.us/img15/1236/jemdiagram1.jpg) which is what
I was going to use. I just bought a Blue Velvet for my custom jem and I'm wiring it
up with a SS in the bridge and an EVO in the neck. I thought the BV was RWRP but
as it turns out its not. From what I understand I will get a 60 cycle hum in the 2 & 4
position. My question is, is there anything I can to, outside of buying a RWRP pup, to
not get the hum. One jemsite member told me to reverse wire the SS and EVO pups.
Another member told me that would just put them out of phase and that I would need to
flip the magnets on the BV which I have no clue how to do. Any advice would be
greatly appreciated. *** Just so you know, I play metal and mostly use just the bridge
pup. I sometimes use the 2 position, but just for a clean sound.

[toneboy]

Just to be clear, did you buy a Blue Velvet middle position pickup or did you buy the neck or bridge? The box will plainly state which one it is. If you bought anything other than the middle position, positions 2 and 4 on your have way switch will not be humbucking.

The principle of humbucking dictates that the 2 coils be wound in opposite directions (reverse wound) and be of opposing polarities (reverse polarity).

As I stated in your other thread, the only way you're going to get anything but a middle position Blue Velvet to be humbucking (in positions 2 and 4) is to the following (2) things:

1) Flip the hot and ground wires in the wiring schematic. This is easy to do.

2) Flip the magnets (polepieces) upside down. I've never done this myself but I don't imagine it will be that easy. If you don't feel comfortable doing this then look for a local guitar tech who is.

I'm afraid there is no other way to get positions 2 and 4 to be humbucking without a RWRP middle single. If you don't want modify the pickup you have then I suggest you buy a middle position Blue Velvet (they're $54 on the bay) and sell the one you have.

[Jem7RB MK]

Originally Posted by toneboy

As I stated in your other thread, the only way you're going to get anything but a middle position Blue Velvet to be humbucking (in positions 2 and 4) is to:

1) Flip the hot and ground wires in the wiring schematic. This is easy to do.

Actually, you didn't, you said it wouldn't work

Now, if you reverse wire it, you should cancel the hum by running it "out of phase" with the other coils (from the humbuckers) i am pretty sure DiMarzio will have a schematic for this, so drop them a line.

I have some pretty funky diagrams for 3 s/coil setups using megaswitches, but none of them really single out what your after

I hope that helps a little

Rob

[toneboy]

Originally Posted by Jem7RB MK

Actually, you didn't, you said it wouldn't work

Actually, I said that just doing that won't work. Put the pickup out of phase is not enough. All that does is reverse the direction of current through the coil. It doesn't account for the difference in the polarity of the magnets between the Blue Velvet and the coil of the humbucker. You have to reverse the phase and reverse the polarity.

Now, if you reverse wire it, you should cancel the hum by running it "out of phase" with the other coils (from the humbuckers) i am pretty sure DiMarzio will have a schematic for this, so drop them a line.

Again, that won't work. Dimarzio has a wiring diagram for HSH on their site. Here's a link: Dimarioz Hum/SC/Hum wiring diagram (PDF format)

In the wiring diagram it specifically states:

"If you're using a standard Dimarzio single coil pickup in the like a Blue Velvet, you should get a reverse-polarity model (DP170S or DP171S) and wire it so the black wire goes to the 5 way switch (the same as the JEM shown in the diagram) and the white wire is grounded to the back of the control."

ETA: It's easier to follow the wiring diagram on Dimarzio's site because they don't just give you a diagram, they also explain how the wiring works.

[tzoranski]

Originally Posted by toneboy

Just to be clear, did you buy a Blue Velvet middle position pickup or did you buy the neck or bridge? The box will plainly state which one it is. If you bought anything other than the middle position, positions 2 and 4 on your have way switch will not be humbucking.

The principle of humbucking dictates that the 2 coils be wound in opposite directions (reverse wound) and be of opposing polarities (reverse polarity).

As I stated in your other thread, the only way you're going to get anything but a middle position Blue Velvet to be humbucking (in positions 2 and 4) is to:

1) Flip the hot and ground wires in the wiring schematic. This is easy to do.

2) Flip the magnets (polepieces) upside down. I've never done this myself but I don't imagine it will be that easy. If you don't feel comfortable doing this then look for a local guitar tech who is.

I'm afraid there is no other way to get positions 2 and 4 to be humbucking without a RWRP middle single. If you don't want modify the pickup you have then I suggest you buy a middle position Blue Velvet (they're $54 on the bay) and sell the one you have.

First I just want to emphasize that I don't really know anything about pups and wiring,
so I apologize if I'm asking stupid questions. To answer your first question, it is a
BV bridge pup that I bought off ****. So if I understand you correctly, since it's not
the middle BV pup, positions 2 and 4 will not be humbucking unless I do both of the two
options you gave me. Otherwise I'll have to get the middle pup or get used to the hum.

The second option sounds easy enough but the first one is a little confusing. Where
exactly is the magnet on the BV? Would it be the pole pieces or is it something inside
the pup. Another member told me that by flipping just the lead and ground, all I would
be doing is making it out of phase. Again, I really appriciate you to trying to help me
understand this.

[Jem7RB MK]

I just re-read your original post, it has 5 wires in total ? if so, it's got 2 coils, hence should be humcancelling anyway

Regards

Rob

[toneboy]

Originally Posted by tzoranski

First I just want to emphasize that I don't really know anything about pups and wiring, so I apologize if I'm asking stupid questions.

No need to apologize. Your questions are not stupid.

To answer your first question, it is a BV bridge pup that I bought off ****.

Gotch ya.

So if I understand you correctly, since it's not the middle BV pup, positions 2 and 4 will not be humbucking unless I do both of the two options you gave me. Otherwise I'll have to get the middle pup or get used to the hum.

You are correct.

The second option sounds easy enough but the first one is a little confusing. Where exactly is the magnet on the BV? Would it be the pole pieces or is it something inside the pup.

Your first guess is correct. One a standard (non-hum cancelling) single coil, the pole pieces are the magnets.

Another member told me that by flipping just the lead and ground, all I would be doing is making it out of phase.

That is correct. When you have (2) pickups, reversing the hot and ground wires in the wiring schematic will just make the 2 pickups out of phase with each other when both pickups are on.

Again, I really appreciate you to trying to help me understand this.

One other thing I would suggest is look up "humbucker" on the Wikipedia and you'll find text and pictures that explain how humbucking works. As you already know, humbucking can be achieved with (2) coils in a single pickup or (2) coils from (2) different pickups. The basic principle is exactly the same in either case.

[toneboy]

Originally Posted by Jem7RB MK

I just re-read your original post, it has 5 wires in total ? if so, it's got 2 coils, hence should be humcancelling anyway

The OP is referring to the humbuckers. The Blue Velvet is plain ol' single coil so it only has (2) wires, hot and ground.