Steel guitar pickup rewind....

[Possum]

Anyone have any info on this type of steel guitar pickup and some sane method of rewinding an air coil like these are. I have 2 to do, both were lacquer potted which is why they are dead I'm sure.....thanks

[Spence]

That's not an air coil. You have a cardboard bobbin there. Air coils have no bobbin. Just be careful cutting the old coil off.

[Bruce Johnson]

You could make up a core piece from balsa wood, cut with the end grain facing up. Wrap the balsa with a layer of clear packaging tape (which is very glue-resistant stuff), and fit it with the cardboard flanges. Then figure out some way of attaching the balsa core to your winder faceplate. Double-sided tape would probably do it. After winding and potting, knock the balsa out. If it's really stubborn, drill through it in a few places and chisel it out. Balsa wood is great for one-use fixturing like this

If I were doing a production run of them, I'd mold up some kind of a flexible rubber plug. It would fill up the center slot and hold everything together during the winding and potting, then just be popped out and reused.

[Possum]

Well it kinda is an air coil, its not wrapped around anything, the coil is naked on the interior, the guitar strings go through the coil, the plastic stuff you see there is all warped from age but is there to protect the interior of the coil. The fiber bobbins if you knocked them off it would be a true air coil. The whole thing is lacquer potted.

[David Schwab]

An air coil means there is no steel (or magnet) core in the middle of the coil. It has nothing to do with having a bobbin or not. I guess that would be called "bobbinless"?

So that pickup would be an air coil. Where are the magnets?

[Possum]

I call it "braless." The magnets are on the outer ends of the steel frame that encloses the whole pickup, they look like steel, maybe cobalt, dunno. Cool design but only works with the strings going thru the coil....

[Spence]

An air coil means there is no steel (or magnet) core in the middle of the coil. It has nothing to do with having a bobbin or not. I guess that would be called "bobbinless"?

So that pickup would be an air coil. Where are the magnets?

Without magnets it's not a pickup. There have to be magnets around it in the assembly.
It's clearly not bobbinless and it is therefore not an aircoil. Open up some Burns and you'll see what an aircoil is.
The thing is that this isn't helping Possum get over this problem.

[jonson]

I did a thingy like this about 20 years ago and made up a base and an upright out of plexy which I fitted to the face plate. Sprayed the whole assembly with a couple of coats of dry ptfe lubricant from my tool suppliers and jammed the top and bottom in place. I wound that with self bonding wire wetting each layer with meths(alcohol) but lacquer potting as you go should do the jobbie. It slipped straight of afterwards.

[Spence]

You can buy self bonding wire too. Here's an example of a coil wound in such a way :



and here's one that's been covered with an elastic insulator :

[David Schwab]

Without magnets it's not a pickup. There have to be magnets around it in the assembly.
It's clearly not bobbinless and it is therefore not an aircoil. Open up some Burns and you'll see what an aircoil is.
The thing is that this isn't helping Possum get over this problem.

Spence, the word "air" in air coil means there is no ferromagnetic material in the core. The core is air. Air cores have lower inductance. The old Bill Lawrence acoustic guitar pickups used air coils. The magnets were not in the middle of the coil.

Another example of an air coil pickups with self standing bonded wire are Q-Tuners:



You can se that the self standing bonded coils don't have a core, but they do have neo magnets sitting in the lower half. Most of the coil is empty.

Google "air coil" and you get the following:

Introduction to Air Cored Coils

We'll use the term 'air core coil' to describe an inductor that does not depend upon a ferromagnetic material to achieve its specified inductance

Another link:

Air Coils

I'm aware that bobbin-less coils, such as in the Burns Trisonics are often called "air coils", but that's not what an air coil is. The Burns pickup also have a steel plate under the magnet, so it's really not an air coil.

As soon as you stick a magnet in the middle of the coil, it is not an air coil. Some pickups are wound like an air coil, but they aren't. Air coils can have bobbins, but they can't have cores.

[jason lollar]

you will need to recore that, cut a piece of wood about 1/16" os so smaller than the hole in the red forbon and wrap a piece of thin cardboard arond it- over lap the seam about 1/2" and glue it. Slide it off the form. fender used cardboard before that plastic crap.
43gauge is always used on those- i dont recall if that one has 920 turns on it or not- its a really odd ball one- usually I get the trapazods in.

[Spence]

Spence, the word "air" in air coil means there is no ferromagnetic material in the core. The core is air. Air cores have lower inductance. The old Bill Lawrence acoustic guitar pickups used air coils. The magnets were not in the middle of the coil.

Another example of an air coil pickups with self standing bonded wire are Q-Tuners:



You can se that the self standing bonded coils don't have a core, but they do have neo magnets sitting in the lower half. Most of the coil is empty.

Google "air coil" and you get the following:

Introduction to Air Cored Coils



Another link:

Air Coils

I'm aware that bobbin-less coils, such as in the Burns Trisonics are often called "air coils", but that's not what an air coil is. The Burns pickup also have a steel plate under the magnet, so it's really not an air coil.

As soon as you stick a magnet in the middle of the coil, it is not an air coil. Some pickups are wound like an air coil, but they aren't. Air coils can have bobbins, but they can't have cores.

Well, here's a reply to a previous thread answered by our very own Soundmaster G regarding Burns TriSonics. Clearly he's been in touch with Adeson who in turn must be using the wrong terminology. I'll let him know:

Well Ben you've asked a question about one of the most difficult pickups to make from scratch. The original Burns Tri-Sonic pickups were an air coil with a ceramic magnet. The coils are wound on a collapsible former. Once the coil is wound to spec, the former is collapsed from the inside, and the coil is taped completely. Then its put into the cover with the magnet, and then the whole thing is epoxied so it won't be microphonic. The coil is very thin top to bottom, and there is no bobbin.

The new Burns Tri-Sonics aren't made the same, and so don't sound the same either. The only one I know of that makes the Tri-Sonics correctly is Adeson in the UK, and I have a set of his pickups. I don't have anything to pu them in yet, but I will. He uses the actual equipment from the 50's that Burns made their pickups on, and uses the same methods to make them. The pickups are very reasonably priced too. Check out his site and email him about it...he's very friendly.

http://www.adeson.co.uk/

Here's some stuff he told me about their pickups in an email.

Regarding the coils - all early European pickups (Hofner / Framus / Hoyer etc..) were built this way. The coil is wound on a removeable chassis - and then completely wrapped in a special armature winding tape (takes ages to learn this - they are ridiculously delicate!). The whole thing is pulled tight - just like lacing up your boots. The magnets are vintage ceramic (similar to Alnico 2). They have been out of production since the early seventies - I have to have them custom made - and they cost a fortune!!! The coils are then placed arround the bar magnets (the holes in the chrome top covers are purely aesthetic). The whole thing is then glued solid to prevent the brass top covers from causing howling. This is exactly how they were made 40 years ago - and they sound great!!!

Many thanks for your enquiry. Our pickups are identical re-creations of Tri-sonic pickups built between 1960-65. We use the exact build methods and original components - they are even wound on the original late 50's Burns winding machine, making them the most accurate version of this classic pickup - period!!!!! We can easily supply a hotter bridge pickup, however on Brians guitar the "hot" pickup was in the middle position. Most Red Special experts want - neck pickup approx 6.5k, middle approx 6.9k, and bridge approx 6.7k. Apparently these figures are based on Greg Fryers restoration of Brians original guitar. Regarding pots and caps, Brian's were Omeg 220k log B pots with a .022cap, although Burns originally used 500k pots in the 60's.

For the whole set of Tri-sonics from Adeson, it was less than $200 with shipping though this was about 2 years ago. Hope this info was helpful to you?

Greg

[David Schwab]

Well, here's a reply to a previous thread answered by our very own Soundmaster G regarding Burns TriSonics. Clearly he's been in touch with Adeson who in turn must be using the wrong terminology. I'll let him know:...

Yes, I know all about Adeson pickups, as I'm planning on making a Red Special this summer.

He's using the wrong terminology. The reason is air coil inductors are often wound as free standing coils, so people say they are winding air coils. But that's incorrect when it comes to pickup, unless the coils have air as the core. TriSonics are not air coils, they just don't have bobbins. They do have ferromagnetic material at the core, and a steel plate under the magnet.

So where is the air in a TriSonic? There isn't any. But it's a commonly used term for bobbin-less coils.

Possums pickup is also not an air coil, since the steel strings would be the core.

It's all about the inductance of the coil's core. Take all the screws or slugs out of a humbucker bobbin, and you have an air coil.

[Possum]

That QTuner pickup is truly a work of art. That guy is one of the true geniuses of pickup design, too bad he focuses on bass pickups. That pickup is just beautiful...

[David Schwab]

That QTuner pickup is truly a work of art. That guy is one of the true geniuses of pickup design, too bad he focuses on bass pickups. That pickup is just beautiful...

He makes guitar pickups too. I don't think they are as popular. They are very bright pickups. The top end extends way up. They have a good low end too, but to me the top end really stood out. Very clear sounding.

He's the guy that wrote that book on pickups, Animal Magnetism for Musicians. That's an interesting book.

I had a couple of Q-Tuners here to check out. I can't imagine how he secures everything in the mold before he pours in the epoxy. I would think the magnets would want to pull the whole thing together!

[David King]

The Q-Tuners seem to be cast in several stages, not all at once. The holes for the pole pieces are drilled and tapped after the coil and magnet have become a solid armature me thinks.
The guy who has the casting process down is Kent Armstrong. No bubbles in his resin and the threads for the pole pieces are perfectly formed.

[Possum]

yeah Animal Magnetism is a must for any pickup designer. I wonder why all these genius designers always make hi-fi bright pickups? Lace, Lawrence. I've read that Armstrong is really good with casting etc. have never seen any of his stuff...

[David Schwab]

The Q-Tuners seem to be cast in several stages, not all at once. The holes for the pole pieces are drilled and tapped after the coil and magnet have become a solid armature me thinks.

That's a possibility. I assumed he did similar things as in the book, where he casts the pickups with the poles in place. He waxes them so they don't stick.

It's a tricky looking pickup. You have the two self standing coils, and in the bottom of those coils are the magnets. The magnets don't touch anything though, not even the pole pieces! There is a slight gap, and that's in the patent too.

So I'm curious how he keeps everything alined and not crashing together while he cast the thing! Like how does he support the magnets?

Casting in stages might be the answer.

The guy who has the casting process down is Kent Armstrong. No bubbles in his resin and the threads for the pole pieces are perfectly formed.

Yeah he does a real nice job. Probably uses a vacuum. I had a Smith bass and was checking out the pickups (made by Armstrong). I quite sure the pole screws are cast with the rest of the pickup. You can see where the epoxy's surface tension went up around the screws.

[jonson]

I spent some time with Kent back in the eighties and got the whole process noted down and produced a lot of pickups the same way. Guy was simplicity in itself from his winders to his casting process and was quite happy to show you round and run through everything in detail. Apart from them being cast pickups his methods and winders were as archaic if not even more so than the early Fender ones and I still have some 80s buckers in their origional wrappers here. Got some time to spare, so, will write out the process (Kent won't mind) and take some pics and do some sketches. I'll be back.

ps Spence will call this week sorry mate.

[David Schwab]

Jonson, that would be really cool.

Kent must have some interesting stories to tell!

[Possum]

WHAT???? The Q-tuner is a copy of an Armstrong pickup? Ouch.
Kent is interview in the Pickup Handbook thats out, interesting interviews in there, Jason is interviewed as well, Kent's is one of the most intersting interviews, the most boring is DiMarzio, Lollar's is good too...

[David Schwab]

WHAT???? The Q-tuner is a copy of an Armstrong pickup? Ouch.

Not at all... Armstrong was brought up because of the epoxy casting.

The Smith pickup I showed is made by Armstrong.

The Q-Tuner patent is 5354949 in case you want to check it out.

[David King]

That air gap in the Q-tuner between the neo mags and the poles is part of what keeps them listenable. They would be deafeningly bright otherwise.

Actually the Q-tuners have more in common with what Lane Poor was doing. "Bi-lateral twin coils" as Lane referred to them. Lane's an interesting guy too. That kid Adam who supposedly put Lane out of business (by putting out a noisy batch) is also starting to make "those" pickups again. Haven't hear any more about it but it was on Talkbass a while back.

[David Schwab]

That air gap in the Q-tuner between the neo mags and the poles is part of what keeps them listenable. They would be deafeningly bright otherwise.

Yeah, they sure are bright though.. even with the gap. Not much inductance going on there.

Actually the Q-tuners have more in common with what Lane Poor was doing. "Bi-lateral twin coils" as Lane referred to them.

Were Lane's pickups sidewinders too? I get people asking me about Lane's pickups more than any others. I've never even seen one in person. They sure have a mystique about them.

Lane's an interesting guy too. That kid Adam who supposedly put Lane out of business (by putting out a noisy batch) is also starting to make "those" pickups again. Haven't hear any more about it but it was on Talkbass a while back.

Is that what happened? He just disappeared. He had some odd looking basses!

Yeah that Adam guy is making them now, but the people that heard them on TalkBass said they don't sound quite the same, but at least they are quiet now.

[David King]

If you look at the frequency plots you'll see the the Lane Poors have quite a bump up at the top around 2-10K I think. The suspicion is that there are some passive components packed away under that epoxy. The response is anything but flat in other words but it ends up sounding "hifi". I've still got a stash of them and i suppose i could chop one apart for science but chances of that are slim at this point. I like them a lot but they are much more of a "bedroom pickup" than a live venue pickup.
Lane went through a dark time there but I hear he's doing much better now. He still lives on the cape with his family and apparently the whole production facility is still intact in a warehouse in Rhode Island. He locked the door and never went near it again.

[Achiles]

I have 2 LP(1 jb and 1 MM)opaned "for science ".
I dont know how much could i get if i put it on E-bay.
Next week i´l try to put picturs here.

[David Schwab]

If you look at the frequency plots you'll see the the Lane Poors have quite a bump up at the top around 2-10K I think. The suspicion is that there are some passive components packed away under that epoxy. The response is anything but flat in other words but it ends up sounding "hifi". I've still got a stash of them and i suppose i could chop one apart for science but chances of that are slim at this point. I like them a lot but they are much more of a "bedroom pickup" than a live venue pickup.

All pickups have a resonant peak right before the high frequencies start to drop off. If you underwind a pickup the peak is up pretty high.

When I was making the low Z pickups, you couldn't hear the peak because it was so high. That gave the pickups a smoother tone than you would expect, so they didn't seem overly bright.

When I started doing the high Z pickups, my first few were wound a lot lower than I do now, and they also had a smooth kind of tone, and didn't seem all that bright. So I wound them more, which brought the peak down, and now they sound brighter. Seems counterintuitive, but makes sense when you consider that bright pickups actually have an upper mid peak, and punchy pickups have a hump around 100 Hz, and don't go down all that far past 80 Hz. Limiting the band width for instruments seems more musical to our ears, probably because that's what we are used to hearing.

I've thought of chopping up my '77 Hi-A pickup for science, but that wound be like killing a pet I've had so long and having it for dinner. But his patents look so cool, that I want to see those planar tipped poles with my own eyes. I probably wont do it though.

Lane went through a dark time there but I hear he's doing much better now. He still lives on the cape with his family and apparently the whole production facility is still intact in a warehouse in Rhode Island. He locked the door and never went near it again.

Well that's good that he's doing well. He should think about having his pickups made by someone else he can trust. I'm sure they would sell like hotcakes, and he could take it easy!

I'm sure like you, I've always keep an eye on unusual bass makers like Lane. Hey, do you like Harry Fleishman's work? I've always thought those Scroll basses were some of the coolest looking basses.



When I get rich I'm going to buy one of those. And a Kingbass too! Then an old Steinberger, a Kubicki, ACG, Zeta Prism Bass, Les Paul Triumph... a few others.

[David Schwab]

I have 2 LP(1 jb and 1 MM)opaned "for science ".
I dont know how much could i get if i put it on E-bay.
Next week i´l try to put picturs here.

Please do! Enquiring minds want to know!

[David King]

Hey Achiles, the LP post operative photos could attract a lot of outside attention. We might want to rename them or post them on the pickupedia.info site to keep the riffraff coming in off of google to a minimum. That said I'm not sure how much we could learn from them without knowing where his magnets came from.

David S.
I've always been a big fan of Harry's. He's been at it for so long and I'm always amazed at how fresh his ideas are and how far ahead of his time he is. He's also a really fun guy to hang out with.