supro / valco / national pickup

[jason lollar]

Check out what I make now. I am pretty excited, been working on this string through supro pickup for some time now. I havent got it on my website yet. It took a risk to go ahead and make it not knowing how it would work on a guitar but the results are so good now I am all jacked up on it! Of course its just scabbed in on this installation.
For those that dont know what they are looking it its that big rectangular metal thing.The magnets are on each end of the pickup- its a split bobbin pickup that is humbucking but it sounds like a single coil. It has a slightly out of phase tone that gives it a little bit of cluck, quite powerful and clear too.
There is an additional cover that goes over the coils that is not installed.
Dont ask where I found the parts, its a combination of making some of it in shop and having the parts made for me. Now I think I am pretty cool.

[Mark Hammer]

I poked around to see some examples of an original, and found this:


as well as this (a Valco Tonemaster):

I gather this is what you're replicating? Never seen or heard of it before you mentioned it today. Interesting. Initially, I thought it was a pickup for a lap steel, but obviously I was wrong.

In my own limited experience, one picks directly above the pickup of interest most of the time, so the idea of a pickup you can't get anywhere near is something that, you'll forgive me, I have a hard time wrapping my head around. Same thing for a pickup that prevents palm muting of any kind. On the other hand, if it yields a sweet strumming sound, then that's an acceptable loss I suppose.

[jason lollar]

cooder caster

Yes thats the pickup except my version does not have the bridge built in. I beleive it was originally a lap steel pickup. Its the same pickup on the coodercaster - check it out http://www.headstockmedia.com/thedvd.html

yes the strap over the strings is a draw back for many but it doesnt prevent you from dampening- you have to float your hand in front of the cover and you hold it in position with your little finger if needed so you dampen in front of the cover. once you get use to it its no big deal- I played lap steel for a number of years where a cover is common.
The strap over the strings is one reason why I made the chicago steel pickup years ago.
My experience is I wont sell alot of them but I bet I sell several a month. Amazing how many pickups I have designed that require routing your guitar to accomodate for them and people do it.

[David Schwab]

That's very cool Jason! Do you have any sound clips?


Here's the Coodercaster:

[Electricdaveyboy]

Great .....

Hey Jason,
I made one for my SG after I heard the pickup of my old Airline lapsteel.
Those Rock!It made the Sg a total Slide tone monster.

[jason lollar]

no sound files yet and I got a zillion others to get done before I get to this one. Hopefully someone else will make some sound files for me!

[soundmasterg]

Pretty cool Jason! I'd love to hear it in action.

I'd be happy to get sound files for you for any of your pickups if you sent me the pickup(s) in question. There are some really good players at the local blues jam who I could convince to play...I've done it in the past for Wolfe and the pickups in my Strat that he did, and Possum has done lots of clips from that jam with various players. I might be doing some for Tom Jones too. Any oddballs like this particular one I'd have to have a guitar to stick them in, which I don't at the moment. (not something I'd want to modify anyway) If you'd like me to arrange something, let me know.

Greg Simon

[angelodp]

Hi, I am rewinding one of these bobbins, can confirm that the good bobbin is 3.1, trying to match that. I did not make it with 43g wire so now onto 44g to reach the correct level. Is 3.1 a typical level for these bobbins? Should I mis-match a tad, say 2.9 on the one I am working on?

Appreciate any intel. I had to rebuild the bobbin and coat with cyano, but all is well.

[Lollar Jason]

its 44 gauge- once connected in series the coils together measure about 6K- off the top of my head its 5,000 turns each bobbin for the two bobbin type

[angelodp]

Hi Jason, thanks for your input, much appreciated.

[copperheadroads]

I have one of these in for repair as the complaint is the G string is weak
Any one know how the magnets are oriented ? this one has both south towards the bobbins ,which i figured should of been maybe N/S being its a humbucker .

[rjb]

I have one of these in for repair as the complaint is the G string is weak.

Although I have never met one of these critters in person, I have read the original patent- which I now can't find. But since none of the experts have chimed in yet, I'll give it a shot:

Both magnets are supposed to face the same direction.
The magnetic field flows in the same direction through all poles.
The coils are wound out-of-phase to cancel hum.
The two bobbins have opposite electrical phase.

Try this:
Hook up an analog VOM across the pickup, set to the lowest DC voltage range.
Lay a screwdriver (or some handy flat piece of steel) across the poles of one bobbin.
Quickly lift the steel away from the poles; the VOM needle should deflect either up or down.
Do the same on the other bobbin; the VOM needle will deflect in the opposite direction.

This doesn't matter in a one-pickup lap steel because each string is sensed by one pole in one bobbin.
In a guitar with a neck pickup, you can play each pickup solo- but you if you play bridge and neck together, the neck pickup will be out-of-phase with half of the bridge pickup.

As for the weak 3rd string:
You are "supposed" to be able to adjust the pole pieces, which are threaded through the base plate.
Chance of turning a frozen screw in a fragile paper bobbin without damaging the coil - YMMV.
Would the customer be willing to try a string with fatter core wire?

-rb

PS - Just found this thread - it may come in handy down the line....
http://music-electronics-forum.com/t39345/

[ScottA]

I borrowed an old lap steel from a bandmate that had one of these pickups in it.

I noticed that the high strings were weak and what I discovered was that the "magnet" on the high strings was not a magnet at all, just a ferromagnetic spacer. I guess this was not uncommon on lower budget models.

Jason was kind enough to sell me a couple of his magnets and it made that thing scream.

The magnets do both go the same way, and they do still hum cancel for exactly the reason that rjb describes. You only need reverse winding for hum canceling and if the string sensing is very discrete then you don't have to worry about opposing polarity string-to-string.

I've made bridge pickups like this with a Zexcoil format, i.e. all one magnetization but RW top to bottom.

Now if you start displacing strings, it's going to sound real weird, real quick.