Requesting Preliminary Design Critique (Split-Blade Sidewinder)

[rjb]

Greetings,

I’ve never designed or built a pickup, not even from a kit (although I have rewound the world’s simplest pickup http://music-electronics-forum.com/t26723/ ).

But, somehow, this thread http://music-electronics-forum.com/t24481/ and Jason Lollar's post in this thread http://music-electronics-forum.com/t23990/#post204262 inspired this design:


It’s meant to be a split-blade sidewinder with “series aiding” mutual inductance (like a humbucker) instead of “series opposing” mutual inductance (like a normal sidewinder). I solicit your opinions regarding why it won’t work, why it will sound like squealing pigs (until it falls apart) and/or how it can be improved.

Thanks,
-rb

[fieldwrangler]

Rb -

Y'know, you've presented what certainly looks like one of the clearest graphical depictions of your idea, yet I still can't quite grok it.

I'll look at it more closely tomorrow when I haven't been working all day on some possibly remarkably similar arrangements.

Or, perhaps not. Could you possibly add the strings to one of your renderings?

Bob Palmieri

[fieldwrangler]

Dateline: Wednesday morning...

I think the reason for my confusion was that I was looking for the convergence-to-the-center-of-the-box characteristic of sidewinders (which I used to call "horizontally-opposed coaxials") that shapes the string sensing/magnetizing area in the way that I've come to really love.

[rjb]

Could you possibly add the strings to one of your renderings?

Here ya go- I hope a .013-.056W set is OK.
I've also corrected the spacer height and edited the notes.



BTW, how do you like the working title "CharlieTron PAF-90"?

Thanks,
-rb

[jason lollar]

it should work- you might already know it will probably work better if both coils are the same magnetic polarity, just reverse the phase on one and it will humcancel. They dont need to be in phase since each coil only senses one set of strings unless you are going to bend strings alot.

[fieldwrangler]

it should work- you might already know it will probably work better if both coils are the same magnetic polarity, just reverse the phase on one and it will humcancel. They dont need to be in phase since each coil only senses one set of strings unless you are going to bend strings alot.

I will say that once upon a time when I made up a few Strat pickups with side-by-side vertical axis coils sensing 3 strings per coil I found that the functional phase between the coils did seem to make a difference in the way chords "rang;" I recall that the in-phase-across-the-whole-span version felt better to me. 'Course, when set up for hum canceling operation the transition across the void doesn't feel too good to those players who bend the "G" string within seconds of picking up an electric guitar, 'specially when using the neck pickup.

Disclaimer: it was just me checking them out; I never did any double-blind tests with my Pool of Eager Volunteers, also known as my students at school.

[rjb]

it should work- you might already know it will probably work better if both coils are the same magnetic polarity, just reverse the phase on one and it will humcancel. They dont need to be in phase since each coil only senses one set of strings unless you are going to bend strings alot.

Actually, I based it on your description of the "Madison Square Garden" CC pickup. Since I didn't show magnet directions, it may not be clear that the cores, magnets, and keeper are supposed to comprise a makeshift horseshoe magnet. Instead of the original 1 coil, I'm using 2 coils with opposite magnetic polarity- so the 2 blades should be electrically in phase. I think.

...when I made up a few Strat pickups with side-by-side vertical axis coils sensing 3 strings per coil I found that the functional phase between the coils did seem to make a difference in the way chords "rang;"

Do you mean the coils were offset, like a P-Bass configuration? Since I'm squeezing the coils one-above-the-other (on the same vertical axis), would I get the same effect?

'Course, when set up for hum canceling operation the transition across the void doesn't feel too good to those players who bend the "G" string within seconds of picking up an electric guitar, 'specially when using the neck pickup.

I suppose I hadn't thought that through. With the "G" string bent half-way between the blades, you (theoretically) have no magnetic pull on the string & total dropout- is that right?


But that might not matter for me- I was figuring it for archtop or semi-acoustic with medium to heavy strings.


Thanks Jason & Bob,
-rb

[fieldwrangler]

Since I'm squeezing the coils one-above-the-other (on the same vertical axis), would I get the same effect?

Just when I thought I was visualizing this thing correctly, it's time to factor in this little fact.

[jason lollar]

thats been my experience if one coil is north and the other south on an inline bucker like that- you get a null zone in between where the magnets cancel each other out, try it and see as there may be something about your design that works differently, otherwise youll get a phasey sound but no dead spot.

[LtKojak]

I suppose I hadn't thought that through. With the "G" string bent half-way between the blades, you (theoretically) have no magnetic pull on the string & total dropout- is that right?

That might be the case, as Lindy did this design to prevent that:

Welcome to Lindy Fralin Pickups: Fralin Strat® Split-Blades - the Finest Guitar Pickups Available Today!

HTH,

[rjb]

That might be the case, as Lindy did this design to prevent that:
Welcome to Lindy Fralin Pickups: Fralin Strat® Split-Blades - the Finest Guitar Pickups Available Today!

Hey, kewel. I like that.
-rb

[Possum]

Its an interesting design, but the end result is its just going to sound like most any other blade sidewinder pickup, the only only difference is that you've done the right angle turn for the blades to get up by the strings. Your magnetic return on the other hand is set very low so you are going to get a very bright tone coming only from the tips of the high blade tops. Then there's the problem of the housing/cover, plus the gap where two coil windings meet, you may find the gap could be a problem unless they are both the same magnetic polarity on both blades. It does show original thinking though, I like that ;-) So, enough theory, BUILD it and see how it works in real life....

[David Schwab]

It's a lot like this pickup, which is a single coil:

[Possum]

wow, thats a strange one, what is it? Looks like an early version Gibson bass pickup?

[big_teee]

It's a lot like this pickup, which is a single coil:

What's the purpose of the wire wrapped around the pickup screws?
B_T