3Dxy pickups?

[Chris Turner]

Have you all seen these yet?
3Dxy Pickups

What do you think?

[David Schwab]

Interesting. I wonder what it sounds like?

[alexoest]

There's a couple of audio clips here
Pauls 3D Systems ······ Demos

It's a fascinating idea, but I'd expected it to sound fuller.

/Alex

[-Elepro-]

they say coils are oblique like in this picture



...but see the pole pieces and the axis line that I traced... where are the coils????....



.......and....the man that "play" in demos is the same that write "offering new possibilities of sound"? i don't think he can hear any difference....

about stereo scope demos... i think i can have same results wiring in xy mode the two coils of a normal humbucker

[David Schwab]

It's a fascinating idea, but I'd expected it to sound fuller.

Not with those little coils.

[David Schwab]

where are the coils????....

They must be straight up and down, and not angled.

[Joe Gwinn]

They must be straight up and down, and not angled.

That's how it looks. Angling the slug tops and the little neo magnets is for show, as the scheme will work even if they are straight. The scheme ought to be able to detect string motion in both side-to-side and up-and-down directions, if the coil signals are correctly combined. This is really 2D, not 3D, but never mind.

It isn't really stereo, but it may nonetheless sound interesting.

[RedHouse]

Yeah must be.

Also that design would need to have weak magnets as the sting is influenced on two sides rather than one.

Seems if you're going to try to wrap the string in MF just use Jason's (Lollar) wrap-around pickup.
(his next generation shoe)

This design (given in the link) is a hybrid of both styles.

He could use some pointers on potting that assembly into a cover (David?) it looks cheesy with the PVC top/bottom plates and white nylon tape over the coils, very 60's look.

...It isn't really stereo, but it may nonetheless sound interesting.

{Edit} I re-read the description, and withdraw the comment.

[Mike Sulzer]

Have you all seen these yet?
3Dxy Pickups

What do you think?

Not sure what is inside, but let us assume that they are as the diagram shows with angled coils.

The first thing we do not know is the relative polarity of the two magnets. The string could be in a vertical pointing field, or a horizontal one, depending, but it could work either way. In both cases, there is a field component along the axis of each coil, and the coil is most sensitive to string motion along that axis.

if you simply add the signals of the two coils, assuming that they are equally sensitive, you get either vertical or horizontal sensitivity, depending on the phasing, but not both. One must cancel; this is why they their mono mode appears to something other than just addition. Perhaps it adds differently at different frequencies.

The xy scope plot in the demo link is interesting. Does it show that the string motion is mostly elliptical at a given harmonic with a complicated relationship between the harmonics?

[alexoest]

If you connect one set of coils (let's say those oriented from the lower left to the upper right) to one output (let's say the left one) and the other set of coils to the other output, it should be stereo. And as I understand it, the interesting effect would arise from the elliptical vibration pattern of the string rotating from one direction to the other (and the sound from that string panning from left to right accordingly).

I think the idea is really fascinating. Perhaps it could be combined with the principle of current transformer pickups discussed in a couple of other threads recently. With a current transformer, the small coils with few windings would be less of a problem.

That's how it looks. Angling the slug tops and the little neo magnets is for show, as the scheme will work even if they are straight. The scheme ought to be able to detect string motion in both side-to-side and up-and-down directions, if the coil signals are correctly combined. This is really 2D, not 3D, but never mind.

It isn't really stereo, but it may nonetheless sound interesting.

[David Schwab]

If you connect one set of coils (let's say those oriented from the lower left to the upper right) to one output (let's say the left one) and the other set of coils to the other output, it should be stereo.

But would it be? If you wire your 2 pickup guitar to send each pickup to a separate channel it will be "stereo" also. But it's not.

Also are the two coils in phase with each other?

I had a Stereo Vox Phantom XII 12-string guitar. It had three split coil pickups, each half of the pickups sensing 3 courses. So you could have the three bottom courses going to left, and the three to to right. You could also reverse the outputs of any of the pickups. When you had the neck and bridge opposite, and sent to left and right channels it was interesting; but is that really stereo?

[RedHouse]

But would it be? If you wire your 2 pickup guitar to send each pickup to a separate channel it will be "stereo" also. But it's not.

Also are the two coils in phase with each other?

I had a Stereo Vox Phantom XII 12-string guitar. It had three split coil pickups, each half of the pickups sensing 3 courses. So you could have the three bottom courses going to left, and the three to to right. You could also reverse the outputs of any of the pickups. When you had the neck and bridge opposite, and sent to left and right channels it was interesting; but is that really stereo?

Multiple mono outputs isn't "stereo".

A stereo image contains other artifacts besides the point source (usually freq selective delay), those artifiacts lend to the positioning of a source (mono) in a stereo image.

There is no delay or imaging on the string as shown, as the string vibrates one way (away from a pole) it gets closer to the other pole, this effect is called complimenatary output (push-pull) not stereo imaging.

[Rick Turner]

We basically tried this at Alembic in about 1975, and the results were not worth the effort. I mentioned this in another thread as the "quadrature" pickups.

It's an interesting science/art project. The real question for us was whether or not there was a real commercial application, and we came to the conclusion that there was not.

[David Schwab]

Multiple mono outputs isn't "stereo".

A stereo image contains other artifacts besides the point source (usually freq selective delay), those artifiacts lend to the positioning of a source (mono) in a stereo image.

There is no delay or imaging on the string as shown, as the string vibrates one way (away from a pole) it gets closer to the other pole, this effect is called complimenatary output (push-pull) not stereo imaging.

I agree. Your mono amp in the middle of a room is more stereo than a stereo guitar. At least to your ears.

Regarding complimentary output... that's why I wondered if the two coils were in or out of phase.

It might sound interesting in headphones, but to call it "natural 3D sound" doesn't even make sense. Maybe surround sound.

[LtKojak]

The real question for us was whether or not there was a real commercial application, and we came to the conclusion that there was not.

I've never seen this p'up before, and from the first look at it, the question that popped out in my head was exactly that one... and after I thought a little bit about it, I came to the same conclusion.

Is in this case appropiate to say "great minds think alike"...?