What's the deal with those split-blade Fralins?

[Mark Hammer]

Lindy doesn't provide all that much technical info on his site ( Welcome to Lindy Fralin Pickups: Fralin TeleŽ Split Blade - the Finest Guitar Pickups Available Today! ). Given that I've never seen that approach to hum-cancelling single-coils anywhere else, I was curious about what the slightly overlapping bent blades added (or avoided) that would not happen with a pair of straight blades. If it's an industry secret, fine I'll relent. But given that it is out in the open, I figure it's a fair question to ask.

So, why would one want bent blades?

[salvarsan]

Given that I've never seen that approach to hum-cancelling single-coils anywhere else, I was curious about what the slightly overlapping bent blades added (or avoided) that would not happen with a pair of straight blades. ...So, why would one want bent blades?

It's a two coil hum cancelling pickup, a 3+3 package in which there are two magnets oppositely oriented.
The bent blades minimize magnetic field cancelling at their nearest point between the 3rd and 4th strings.

Fender offered a similar concept pickup a few years back which had some iron bits on top of pole magnets for magnetic field shaping but discontinued it. Can't even find an image of it any more

-drh

[Mark Hammer]

Thanks.

So, the bend itself does more, in the way of eliminating field-cancellation than simply having a gap? Or is the bend what increases the gap, relative to a pair of straight blades?

[big_teee]

Fender originally did it with the split P bass, Split Mustang bass, and the Fender 12 String guitar.
That required 2 pickups, and a different rout.
Like Salvarsan said, the bent blades lets the blade extend past the strings, without being so close together.
If you run the straight blades next to each other they would try to cancel out, since one is north and one is south.
IMO a small blade or rail pickup is as good, if you don't over-wind them.
Rails IMO tend to get a bad rap, because they are associated with hot over-wound pickups.
Here's the split pickup that Fender had a few years ago.
https://www.google.com/search?q=fend...Z1DUOto4iIM%3A
T

[Mark Hammer]

I became familiar with that design about 28 years ago when I visited the then-location of Evans Eliminator pickups, that used a pair of yin/yang coils inside a Strat-type cover. More accurately, the coils were normal, but shorter, and the flatwork was yin/yang, so the coils snuggled up against each other inside the cover. The polepieces in the two coils have a space between the D and G strings which is identical to that between A and D and G and B. It would appear that, while the space between the ends of the two blades is probably bigger than that between the D and G polepieces on the Evans, the Fralin blades extend out farther than the coils themselves. What perplexes me is the physics of a blade going out to exactly where the Evans polepieces would have been, and then hanging a left turn. Why does the polarity of the point of the blade where the bend is not create the same cancellation that two adjacent opposite-polarity polepieces would?

I'll be the first to admit my understanding of magnetism is VERY rudimentary.

[salvarsan]

Fender Super 55 Split Coil strat pickups

Here we go. The Super 55's entered around 2011 or 2012 and had some cleverly shaped steel parts to control the opposite mag fields.

static.weloveshopping.com/shop/music-boulevard/H74364.jpg



-drh

[Richard]

How did they sound? I played around with a T-Style with the split Fralins for a couple of minutes in GC and I didn't hear the chime I was hoping for. I have some Fender Vintage Noisless that do okay, when I split the coils I get a LOT of chime.

[Mark Hammer]

Well that's downright provocative! So, these things have the polepieces reversed for each coil AND a ferromagnetic slug for shaping the field? Or does it simply have 6 slugs and a shaped bar magnet on each coil?

[Mike Sulzer]

....the Fralin blades extend out farther than the coils themselves.

So the bent portion of the blade is on top of the coil, not through it? If so, then this is just a very visually attractive way to guide the field lines out of the way so that the field with the wrong polarity is weaker when it subtracts from the intended field over the neighboring string. Remember, the flux wants to go through high permeability material, so steel guides it to the side.

[Jason Rodgers]

The inner ends of those "guide" bars have a very specific shape. Almost like they came from something else and were reused.

[ScottA]

Making a "linear humbucker" work, at least in the neck, comes down to closing the magnetic seam between adjacent pole pieces with opposite magnetic polarity.

Consider something like the Novak dual coil pickups. Fine for the bridge, the strings never translate very far from right above the pole piece, but in the neck you'll have noticeable dropout when bending the G, or even when hitting the D hard.

Lindy's design, as well as the Fender Super 55, uses a permeable extension of the pole piece to intrude into the gap.

I use short "blades" on an angle and position them so that the pole pieces themselves overlap, as the string sees it.

[Mike Sulzer]

Making a "linear humbucker" work, at least in the neck, comes down to closing the magnetic seam between adjacent pole pieces with opposite magnetic polarity.

Consider something like the Novak dual coil pickups. Fine for the bridge, the strings never translate very far from right above the pole piece, but in the neck you'll have noticeable dropout when bending the G, or even when hitting the D hard.

Lindy's design, as well as the Fender Super 55, uses a permeable extension of the pole piece to intrude into the gap.

I use short "blades" on an angle and position them so that the pole pieces themselves overlap, as the string sees it.

But notice how Fralin's pickup works: if you bend the G sting into the gap, centered, you have symmetry: there are two equally but oppositely magnetized regions on the string, guiding flux from the vibrating string into oppositely wound coils. That is, this "linear humbucker" becomes a dual blade humbucker in the gap.

[ScottA]

But notice how Fralin's pickup works: if you bend the G sting into the gap, centered, you have symmetry: there are two equally but oppositely magnetized regions on the string, guiding flux from the vibrating string into oppositely wound coils. That is, this "linear humbucker" becomes a dual blade humbucker in the gap.

I know exactly how Lindy's pickup works. It isn't really a dual blade humbucker in the gap, though. The cores don't overlap there. The part that overlaps is an extension of the blade that extends out of the core and protrudes over the windings to close the gap.

On my pickups, the cores do overlap.

[Mike Sulzer]

I know exactly how Lindy's pickup works. It isn't really a dual blade humbucker in the gap, though. The cores don't overlap there. The part that overlaps is an extension of the blade that extends out of the core and protrudes over the windings to close the gap.

Well, I guess that depends on how you want to define things. The operation of the Fralin pickup is quite different centered in the gap rather than away from the gap. Centered in the gap you have signal from from two coils contributing equally resulting from reversal in both magnetic and electrical polarity, and two regions sampled on the string. That is much like a standard humbucker, and both rails are involved. Away from the gap signal from one coil dominates and there is just one sampled region.

I did not imply that you do not know how they work. I just think it is interesting, and it had not been fully explained here, I believe.

[Jason Rodgers]

I'll say again: the inner ends of those little bars have a very particular shape, what with the little curve and notch. Would it do the same thing if the bars retained their cross section along their length? Or is there something special about less metal at that overlap? How about a taper, like a gapped scarf joint? I'll buy the possibility of that space effectively acting like a dual-blade humbucker, but why that shape?