Seymour W. Duncan's Interview With Seth Lover
In June 1978, Seymour W. Duncan visited Seth E. Lover – inventor of the Gibson ‘Patent Applied For’ humbucking pickups – at his home in Garden Grove, California. Seymour and Seth later went on to develop the SH-55 Seth Lover Model humbucker. Here is that historic discussion as transcribed by Seymour in 1995.
I guess I’ll start with where you where raised and born and where you raised in California?
I was born in Kalamazoo, Michigan at what they called the Borgus Hospital and it’s no longer there, and a new one built outside of town. Where I was born I believe is now the Upjohn Company. They make drugs and so forth. I lived there till I was about seven years old and my parents moved to Hastings. From Hasting, Mich. I stayed there till after World War I then we moved to Muskeegan. Then in 1921 I was sent from Muskeegan I was sent to my grandparents in Pennsylvania. I lived with them till they both died then I went to work with another guy on a farm there and while I was still with my grandparents I built my first radio about 1922-23. I’d been interested in radio and while I was working on another farm I took a radio course “Radio Association of America.” A.G. Mohawk, President I can remember that. and I was really disappointed in that course because I was supposed to get parts to build a large radio, instead of that I got an “Airline” radio already built. [Laugh]. Less batteries and speakers. So I had a little money in the bank and took it out to buy batteries and a speaker for it and I wanted something I could put together. After I left there I left the farm and left for Michigan, I got about 5 miles from where I worked and took on another job because I was short of funds and stayed there and worked for him for a couple of months. Then I went to work for another guy for a month and then went to work on the railroad and I was 17, I told them I was 18 and they were hiring back in 1927 and I was, we called it “high hidden diamonds,” digging the rocks out between the ties and taking all the dirt out and sift it, throwing all the rocks back in, then pound it underneath the ties to bring em up, tighten them in there, I think they called it “Gandy Dancing” in some places. Then they started working us overtime, that was kind of funny. The guys were complaining because they never knew when they were going to get home at night, the foreman would never tell them whether they would work overtime the next day so all of them decided that after eight hours they were going to lay their tools down and leave so sure I went along with that, seemed like about 5 of us walked off, I had about 2 months seniority so I didn’t last long. [Laughs].
They laid me off and hired a guy who has less time then me to come back to work. So that was the end of me working on the railroad. Then I went to work for a guy in lumber cutting down trees. That’s where I got swatted in the face with a limb that was caught on another limb. I gave it a push and it came back and whapped me in the face. And I finally had to go to the hospital to get it sewed up to stop it from bleeding. So then I went to work for a guy who was working for an old man, he must of been in his 60’s and it didn’t sound like a good proposition to me so I joined the Navy. The only thing is I had to go to the local Doctor and he said I had flat feet… [Laughs] So that let me out of the Navy, I tried the Army and they accepted me! [Laughs].
So I went into the Army from June of 1928 till June of 1931. While I was in the Army I took another course, another radio course, National Radio Institute. I got quite a bit out of that, it was a good course. The only thing is when I joined the Army a cousin of mine went along with me. I wanted to get in the Communications Radio section and my cousin wanted to get in “Horse outfit.” Well I got in the Horse outfit and my cousin got in the Communications section. We were both in the same outfit, 16th Field Artillery. He was in the Head Quarters Battery and I was in Battery C. That was the “Great Horse Battery” the ones that had a show team when some high muckity muck died like when ex-president Taft died I remember going to that funeral riding a horse and we where called the escort for him.
His casket was put on a cason and we went down into Washington, DC to Union Station and took the casket over to the church waited out there while the ceremony was going on and then after that we came out we took him to the Arlington Cemetery and buried him (Taft). And who ever was buried in Arlington Cemetery the 16th field Artillery and the 3rd Calvery was stationed at Ft. Meyer, VA right along the Arlington Cemetery, one would furnish escort and the other would furnish body bearers so we spent a lot of time there. Then I got out of there and went back to Kalamazoo, decided to go into the radio repair business because somewhere in the last course they supplied me with about 100 cards saying I was a radio technician.
So I started fixing radios from about 1931 to about 1935. I either worked with somebody or had a shop of my own… then I didn’t have enough finance to make a go at it and took a job with the M & T battery and Electric Company in Kalamazoo. They were the Delco Distributors of automotive parts, car radio and at that time 32 Volt home radios. Power plants out in the country were 32 Volts DC. You had your own home lighting plant, there was no wires at that time and I did their auto radio installations and repair and home radio installations & repair. Then in the early spring of 1941, Walt Fuller at Gibson contacted me, I had known him for quite a while, he wanted to know if I wanted to come to work there, so we talked it over and it looked like a better future than where I was working so I took that job (Gibson).
Then in the winter in December when the war came along, having three years in the Army it wouldn’t be long before they’d be knocking at my door greeting me, I started investigating the possibility of enlisting in the Navy. They would take me then – flat feet and all [Laughs] – that I could go in as a Second Class Radioman, which they didn’t have technicians at the time it was Radioman, so I took that on and they sent me to Treasure Island in California and I went through there school there and it was called Radio Material School (RMS) and they gave us all a test when we got out there.. I was in class 3B… .we started part way along their course, we missed a lot of basic theory that they gave to the earlier classes in 4 and 5.
We went through much AC and DC theory and got into their transmitters and receivers, sonar and radar in special service, Oh yeah! when I first went into the Navy in December of 1941 they sent us to Connecticut first until they had enough people gathered together till Treasure Island was ready the influx of people at the time. When we got out there in February 1942 we had to move a bunch of bunks to get things into place. I finished there in August and they figured they need some teachers so they sent me and a bunch of others guys back to Chicago. They gave us a teachers training course, they took us 30 days, got a leave and went to Washington, DC to Silversprings Maryland and started teaching school there. Taught theory, lab etc.
I was made 1st class I was made Chief Petty Officer. They sent me to the Navy building to write examinations. That was 30 days special duty and after 30 days, they renewed it for another 30 days. That was the end of it and I was put on a ship in Boston that wasn’t commissioned yet. Went to Boston and waited by checking spare parts. We where on board, checked in spare parts, radio, sonar etc. We headed out to sea, we got out about 500 miles and the drive shaft wasn’t working right and had to turn around and for that I got my American Theater of Operations ribbon [laughs]. I got back into port and had to cut a big hole along the deck to get the drive shaft through and put in another one and weld all that stuff back together. By that time the war was over and you would get out with points to burn.
After it was fixed I was sent to Guantinimo Bay, Cuba and we made sure the ship worked we were sent back to Boston and I was out of the Navy in October, 1945. I went back to work for Gibson and worked for them about eight months before the war and, so I went back to work for them and was doing more engineering and developed one of their pickups you’ve probably seen with the rectangular magnets that screws up and down, individually adjustable, it first came out on some hollow body guitar… I’ll go get some of those pickups, I have a bunch out there in the garage… here it is, that’s the pickup the first one’s.. shortly before this one was brought out, DeArmond brought one out that had a very large magnet pole piece that was adjustable up and down. It had individual screws and Gibson felt they needed something to compete with that so I designed this one (Alnico pickup with rectangular Alnico magnets) the pole piece are adjustable rectangular magnet.
How was the bobbin made? Was it cut out with a routing template?
No… this is a handmade coil form made from a rectangular piece of celluloid and we glued the ends on, drilled the holes out and filed it out to shape to fit the rectangular magnets and this was one of the first hand made ones made. The magnets were so strong on this and if you got it too close to the strings, it would vary the tone and you would get what they call “Woof” tones and that never went over too well, I don’t know whether they made a hundred or two hundred of them and quit.
Where all the bobbin made by hand or at that time was a special tooling made?
No unless we got into real quantity we made them by hand, before that the ES-125 pickup eventually had a bobbin made for that, called the P-90. The next one that I made for them was a bass pickup. The non humbucking bass pickup with a single winding with the magnet up one end and the screw up at the other end and between that I designed a number of amplifiers for them. I worked for Gibson from 1945 to 47 and just designed amplifiers and no pickups at that time…at first and designed an amplifier called the GA- 50 model if I recall and that’s the one that had a pair of 6SJ7 tubes that were balanced and had tremolo on it.
It was the GA-50T (tremolo) you would drive your signal into one 6SJ7 and had another 6SJ7 that was connected out of phase with that first one and drove both of those grids with a tremolo signal, in the plate circuit the tremolo if the circuit was equally balanced would balance out.. I still have the schematics out there in the file cabinet out there too and at that time the first two years after that from 45 to 47 I didn’t do any pickup work that I could recall… If I did, I don’t remember and at that time I didn’t feel they were paying me enough and had a chance to go back in the Navy at the training center in Kalamazoo, Michigan as a station keeper, I installed the radio, radar, CIC equipment, receivers, transmitters, built a code practice table all kinds of things to use in the training center there and that paid better than Gibson wanted to pay.
Then in 1952 the Navy decided it was long enough for one to stay in one place… so I contacted Gibson and they made it worth my while to stay there, rather than move. Ted McCarty wanted me to design a pickup for them and that was the thing I worked on first just before I got out of the Navy till I got out and was working full time for Gibson. I designed the non-humbucking bass came along then somewhere along in there is when I designed the three-pickup job or a triple job for the steel guitars. That’s the humbucking pickup patent drawing (Seth is showing me the drawings-SWD) That’s the Rhodes Piano pickup patent they still haven’t used… maybe someday…
Here it is, there are three rows of magnets, one all the way across, one at the bass, one at the treble and then the switching circuits for the switch that you added one, would be the center pickup by itself, one and two was the other pair and all, I’m not sure… that was the neck selector, 306954, there was bass, when the bass was added in.. that was a selector switch to give you different connection of these coils and was filed January 9, 1957… no that was when the patent was granted. There was one position called Chime, one they called Treble, and I think that was Normal and Bass. There should have been a schematic with that… lost in the shuffle. I have several copies of the original humbucking patent and here’s a speaker design patent I got while working at Fender and also a patent on the speaker (Des. 229,289)This is a design and shows the grill cloth and how I pulled it back in… looking from the outside it looked like a curved linear speaker, they built the speaker but kept the front flat and never used the design patent.
Here’s the article I wrote for guitar player magazine… this is what I wrote and sent to them and these are the drawings I sent along and I’m still getting letters and just got one last week… here’s the patent and how I mounted the four speakers in the cabinet and at an angle… you know how you yell at someone across the street and they don’t hear you and you cup your hands and that’s how the idea came from… .we fastened the screw under the Fender logo to tightened it down. Here’s a good copy of the patent you can have and send back when you’re done. Every time they issue you a patent, their supposed to give you a dollar… when your working for a company (Gibson) they give you a dollar… The first dollar I ever got! [Laughs]
I am currently working for Logic Research Labs. Dave Love was the president and chief engineer… they never got into production and not enough produced before they made changes and went bankrupted. I work for the people who took it over. They make a mechanical Leslie sound and also make foot pedals. Here’s the patent for the tine on the Rhodes Piano.. I was able to get the harmonics since they were unable to before. Before every time you hit a note it would sound like “ooh ooh ooh” (rhymes with you) and have a non-consequential sound, you get up to the treble end… sound pretty good… you get to the bass end… sound pretty good, in the middle register about an octave below the middle “C” and octave above middle “C” sounded sour and didn’t sound like piano… by changing the pole piece I was able to change it from a response of this nature to this which when they wanted to get harmonic content they had to move the tine closer to the middle…they could never get enough harmonic content before they canceled the fundamental, this one here by forcing the magnetic field off to the sides you could get the overtones. This particular patent they had 43 claims on it for my humbucking patent I had one! [Laughs]The piano pickup patent is (3,069,954).
Tell me about your humbucker.
This is the original Humbucking pickup I had made and given to the lawyers and made their drawings form that…Lover (2,896,491)…it didn’t have to be taken apart and they asked me how it was constructed and I told them. I had tabs folded over and was a hand made sample that was not a production unit… later on when we started making them I drew covers and we fastened everything together with screws and the cover was solder fastened along the edges on the final assembly.
When you get a patent… somewhere it ways 1 claim… they always list references cited. Here I have Lesti’s (Re. 20,070) patent cited and a copy of Lesti’s patent and sure enough he had two pickups and see how he did it… he had electro magnets… he’d throw the switch one way… he applied for his in 1935 and in 1955 is when I applied for mine… that’s when they referred mine back to his… he had humbucking construction, he merely did it with electro magnets, he magnetized the strings, so that was one of them… the next one was Knoblaugh (2,119,584)… he also had double coil construction so connected that it gives humbucking action but he also applied DC… he switched back & forth…
Arnold Noblaugh… this is setting underneath the strings… I assume that what he means by these things across here… he might have had 16 strings… by magnetizing, one on top of the other, an iron core flush with the top & bottom… the iron core magnetizes the strings and the string is magnetized and moving that over a coil induces the voltage… so that’s the way Noblaugh did it… Here’s Russell’s (2,262,335)… patent and a horseshoe shaped magnet but he had a raised pole pieces with the strings going through the holes… .here is his U shaped pickup and had holes in the magnet… he was first to use a permanent magnet and the other two guys used an electromagnet… .that would have worked but at the time (1939) there were no solid body guitars to speak of but maybe some experimental models so when you put the weight on top of a hollow body guitar you deaden the thing… you lose the overtones… you dampen the body… back then people who played guitar were very fussy about what they heard and if the amplified sound and if it didn’t sound like a guitar exactly the way, how they thought it should sound, they’d rather be caught dead than play an electric guitar. Another is Alverez (2,542,271)…
I don’t know why they mentioned that one… . they say a device for creating oscillations, it didn’t have anything to do with what I was claiming but in the early versions of the patent application the lawyer made some reference that caused them to dig this one out and claim it as a reference… that was filed in 48… the next is Grimshaw (2,581,653)… here is another one I couldn’t understand why it was reference… it had a single winding and adjusting screws on the end… in this picture and it’s still a single winding… .Grimshaw is from London, it says… something simple to manufacture employ a minimum number of parts.. simple to assemble and adjust to require no or very little alterations in construction of musical instrument…now his claim he didn’t claim any humbucking action so forth and got 7 claims… just why they referenced that I don’t know…I do know that we mentioned ours being simple so forth and maybe that what they referenced that to…
Then the next one was Keller (2,683,388)… now this looks strangely like this one here but the coil is turned sideways, the mounting screws slightly off center and now why they referenced this one, I really don’t know either… .because it was a single coil, and maybe something in the language said something the same as I did and compared the statements and so just why it was referenced and no claim for humbucking I don’t know… .I think you can have some lawyer in Washington search and go through the files buy when you make an application for a patent, they search files under the same heading “electric translating device for musical instrument” so they go through their musical instrument file and dig through all the things and if there’s something that references the same thing… I assume they must have something that reads that for them. I can’t see them sitting there reading all the patents, it would take them for ever… and this one here since I couldn’t read it, I couldn’t find anything humbucking in that… they were using a magnet top and bottom and could magnetize the strings…
Here is a patent of Leo Fenders (2,817,261)… shows the Stringmaster when the volume is up all the way the pickups are in series and humbucking… they could turn one side off when the volume control was turned down it would use one coil… or single coil…
Why do they call it an electromagnetic pickup? you usually think of a pickup with a electrical current going through it.
I don’t know why they call it electromagnetic… it’s a generator… your changing mechanical motion and changing it into electrical energy, it’s a generator… that’s why lot’s of times they like using the work transducer that sounds a little more modern. I don’t know why they use that term, there are electro magnets and permanent magnets… anytime you change the statement in the patent that’s been started through you must make declarations and so forth… it gets quite fuzzy at times…I came across my original notes the other day for the humbucking pickups… I believe the pickups (Alnico) was used on the ES-175 and keeping the plating on the magnet it was first with copper plated, we had the magnet copper plated then I could solder to it… .the wire was grounded to each pole piece because if somebody would happen to touch those it would “tick”, because of capacitive coupling… your body picks up fields that are radiated through you, if you touch something of a different potential there is going to be an exchange of energy between your body and another object being the pickup pole piece, like static, since traveling from this body to that body at different potential, OK that current is going right through the coil so it will make a little pop… if you touch the strings you will hear the click… I’ve seen guys play with a strap around their wrist to ground themselves to the guitar to get away from that! [Laughs] I’ve heard some stories but never have tried it myself, if you keep the bridge, strings, etc. all insulated and don’t connect the tail piece through the ground system that you get away from that… I’ve never found a time when I could do that and never investigated it but seemed we had more noise when isolating the tailpiece from ground.
Was your first humbucker bobbins wound by hand?
How did the tooling hold the bobbin?
What I have on my present one we had on the Gibson ones, a flat plate that was connected to a shaft that was rotating… that plate would go through here and bolts that would bolt the system together… and this is typically what happens… they bow, they bow at the ends from the winding pressure… the more turns you have the more pressure they tend to give a little… and that’s one of the things by going to a heavier plastic you can sort of tend to control that… .the prototype Alnico (staple p.u.) was wound by hand… I’m pretty sure I wound this one myself… I believe I made this pickup around 1952… that’s when I went back to Gibson… … ..the first of July of 52 got out of the Navy and went back to Gibson… I was working on this prier to joining Gibson and when I started working full time I finished this one up.
Did you always use 42 AWG magnet wire Plain Enamel?
42 was the size wire to use if you were doing something economically… if you go to 44 you stand more chance of breakage and while the additional DC didn’t mean to much to you… .as long as you keep the volume control impedance at the right value, say 250K volume control you tend to load it down a little more… but if you went smaller in size to 40 you couldn’t get enough turns on to give you the amount of output… because the one major measure of how good a pickup is, is how loud it is… [Laughs]
Why does the DC resistance vary in pickups?
This one here (Alnico Staple) was wound I believe with 10,000 turns of 42 PE… I’d been trying to think how many turns I put on the coil of a humbucking… it seemed to me it was about 6,400 turns… but than I think that it was a little high but it was in between the 4 and 5k range… some of my earlier data suggested that I had 4,200 to 4,400 turns, then I got to thinking, didn’t I have more turns than that on it… it seemed to me I had more turns on it. I’m not sure but I can take this one apart and unwind it.
Are the coils made by hand in the prototype humbucker (PAF)
Yes, that’s right, the coil forms are made from celluloid with a bar magnet underneath with iron pole pieces on each side, you see when I first designed this I had the cover plain on the original one… I wanted them to sell it without any adjusting screws because I found that with this there was much difference between the first and second strings like there is on most of the old non adjustable type there was quite a difference in the first and second string but this didn’t seem to have that major difference, and I thought it was not necessary to have pole pieces… well when you take away a talking point from a salesman it’s like breaking off your arm… The first thing I came up with an idea was just fake some things there so I stamped them on the cover, that didn’t please them either, by that time we already made the patent application… that’s why it went through that way, so they finally decided they wanted screws in there, so I put adjusting screws in it for them, then the question they asked me then was which way should those screws set? Should they set up or down? Well you’ve got to give them an answer so I decided to take the one closest to the fingerboard and put the screws facing it and the one closest to the bridge towards the bridge! [Laugh] that made them happy, they had a set way that it should be set, it only amounted to turning the pickup around…
Did you feel the screws in it would change the flow of the magnetic field…
It would change the direction of the magnetic field out the top and also the bottom..
Did you spend a large amount of time at Gibson just developing the humbucking pickup?
Most cases I was doing other things at the same time and I’m trying to think… let me find my note book that had my original notes… this is electric string data that I took back in 1964, this is core wire tinned music spring wire… nil stain winding material, stainless steel, nickel winding material, magnetic, question mark, source, Wilber Driver, at HK Porter. this was a part number for strings the core was so and so, the winding was that and core was that etc. the winding material was Nil-Stain… down here we had nickel, this was at Gibson. Here was some ideas I had back then, see the problem with guitars is the peg head waves around and I was trying to stabilize it but keep it out of the way of the player, because he had to get his hands in there to play it too, and so I was just dreaming things on paper… This is two L 5 pickups split pickups, into three poles and the winding turns were 10,000 and each 5250, electric mandolin pickups. I once made a mandolin pickup, the ES-125 had 5.5 into its’ self resonance, it was a standard than various changes I made and I attempted to get a low impedance output.
Did you design the coil form for Gibson?
Yeah. When I designed something, I designed the whole thing, the bobbin shape, I made an electric banjo, the solid body electric banjo. a mixer unit.
So the first coil forms were made by hand?
Oh yeah – I used celluloid. You’d mix up some acetone and celluloid and from that you’d get a glue. That’s the way you made your glue; you take the chips of celluloid and thin it with acetone until it was in pasty form.
I’ve got a question for you. When a patent was issued, why did Gibson put the number – patent number – 2,737,842 on the bottom of the humbucker instead of your humbucking patent number 2,896,491? On the bottom of them they use the patent number for the tailpiece instead of your patent.
That’s a good question. I don’t know. Did you get a copy of that particular patent number they put on the bottom of the humbucker
Yeah. It’s their patent for the early tailpiece used on ’52 Les Paul’s and other acoustic electric instruments.
I think they just got mixed up. Somebody said you have to put patent notices on so they grabbed them out of the stock room and put the wrong ones on. They had the patent applied for stickers on till the early ’60s or so – I’m not sure exactly when they took them off (PAF). I don’t think they used that too much after they got the patent. It could have been, say, a year after the patent. Sometimes manufacturers feel there’s more protection in a patent applied for sticker than there is with the patent number because as long as there’s a patent applied for, nobody can look at the patent and see what it looks like. Once they have the patent number, then they can. Just how long they use that number, I don’t know.
In ’61 there were a lot of guitars that had Patent Applied For pickups and I didn’t know if they assemble all the pickups and just stuck all the decals on or maybe they had a couple of thousand sitting around and used them at random.
It’s possible. They may have had pickups manufactured that far ahead. I think what quite often happens – you see, those guitars are built up and come down there in racks – so many in a rack. Well, they could get all assembled, down to the final tester and somebody testing it, he looks it all over – gee, there’s something that doesn’t look right in the finish – they have to send it back. So that could show up months later, you know by the time it got around through the finishing… it depends just how much they had to tear down and put back together to complete that. So that could extend the life considerably.
What is the humbucker like in your terminology? What should it be called – electromagnetic pickup or electrogenerator?
I like to call them just humbucking pickups. I call them a generator, because that’s essentially what they are.
Did you design the coil forms (bobbins)?
Yeah, in other words, that was just part of the job when you wound the pickup you had – first you had to figure out how close do you want that thing to sit together. And that’s going to govern, then, the size of the coil from because just half the distance between the pole pieces can be allotted to one half of the coil. So that’s going to govern that.
When the bobbin had a tooling number, did Gibson issue it or is there any reference to what it meant? This bobbin here says M69.
I think that’s just a tooling number that’s put on there by the guy who molds the particular bobbin.
Here is a cream bobbin out of a 1963 Thunderbird bass. Why where they using cream plastic at the time and how many would they mold at a time? Would it be hundreds or a thousand?
Oh no, there must have been several thousand at a time. I don’t think that they ever ordered bobbins, a thousand at a time, because it took two for each pickup and that would only be 500 pickups. 500 pickups don’t go very far. If you have two pickups on a guitar, that’s only 250 guitars, see. That wouldn’t be too many. I know something came up about the cream bobbin back there and I’m trying to think clearly just what it was. I think that we felt that maybe the cream, when you look down through the cover by the adjustable pole piece it would not show as much as the black, the adjusting screw side there, and I think at one time we thought maybe that wouldn’t look, well, I shouldn’t say objectionable, maybe it would look better if it was cream instead of black. And then again I’m not too sure that it wasn’t a case of the supplier calling up and saying “Hey, I don’t have any black, you need these in a hurry, I can run them in cream like the Les Paul mounting rings. Can you take them?” and in either case I would have said yes. But we started out with black and went to the cream for a short period of time and then back to black.
After the first bobbins you had made, were there any tooling problems or anything you had to change in the design after you had the bobbins made?
No. I don’t recall. There was some debate at one time whether we could make more than one spacing. The spacing of the strings near the finger boards are different than the bridge. I wanted to make one for each. Well, that meant making two molds. So I think we settled on one and let it fall where it would on the forward or fingerboard pickup.
Where the coils wound by hand or was the magnet wire guided by machine?
Only the experimental ones were wound by hand. Once we decided to make a bobbin and got our coil forms molded, then we set it up on the machine and I’m trying to think just how many; there was one machine that wound just four coils. I know there was one little machine and then we had a larger machine where we would wind more.
Was the wire guided on by hand or did it have an automatic traverse.
It had an automatic traverse. (The machine automatically layers the magnet wire on the bobbin).
I read an article that someone said earlier humbuckers sounded the way they do because they were wound by hand and the newer ones were different because they were wound by machine.
I can’t recall that anybody wound any by hand except people who were repairing. I wound sometimes, and if an old pickup was sent back in and they didn’t have a machine for winding it then it would be rewound by hand.
Would HPI make the tooling as well as do the injection molding?
I believe HPI made the first bobbins and they also made the tooling for it.
Who would submit the drawing, would you do that?
Oh yes. In fact those old original drawings – I don’t have any more.
When were the first humbuckers used commercially? Early 1957 or 1967?
I suppose 56-57, right along in there. I know when the patent was applied for, and there was no activity from CMI as to wanting it put on until some trade show came along where some competitor had a humbucking pickup. And the story came back, why don’t we have something like that and I said “well you’ve got it hanging in there on the wall, all you have to do is figure out how you want to make the cover. So that brought it to a head and we went into production.
What were the first instruments if you can recall that the humbucker was used on? Would it be the solid body or acoustic?
As I recall, I could be wrong, but I think it was the ES-350. It was not the thin one. It was the full sized body, as I recall, and then shortly after we put it on the Les Paul solid body. They still had the other early style, I guess, the ES-125 with the cream cover (dog ear P-90) that was fit down in the body. And they had that on some because people liked that particular style of pickup. And then we added – the ES-335 – that was a thin model.
How did you figure out the distance between the pickup and the bridge, not making it too close or too far away?
That was pretty much trial and error. You used what was basically used before as the position. And you might have tried it a little forward or a little backwards to see if you could get any particular improvement, but I thing that it was pretty well mind set by a musician as to the position. They liked to have certain – they thought was correct for the pickup. And if you started fighting a musician by moving it to some place he didn’t like you could get into trouble. Now if you came back too close to the bridge you could get it a little brighter, but you had a tendency to lose volume because the string vibration did not move as far. If you lost too much volume because then you were in the dog-house because you were not as loud; therefore, you were not as good.
Did you have players try out the pickups before they wanted to market them commercially?
Not commercially but when you say try out – yes. We had musicians come in and listen and try them out. We also had very good musicians there at the plant. Julius Belson was a very good musician – Wilbur Marker, another one. And they listened to them and – oh I can remember when I was working on the first bass pickup, the non-humbucking bass pickup – Wilbur Marker came in there each time I would get one ready and he would try it out – ”that’s better than the other, but not quite right,” so we would make some changes and go on – wind up another. We finally go to the point where you had to stop – you could have gone on forever and never been exactly perfect. But, now we had some very good years there. When I can begin to hear the differences I make certain tests – I can hear the differences between them and then when they would corroborate what I could hear, then we knew we were getting somewhere.
How did you figure out the number of turns for the type of frequency – if you put too many turns on, when do you start loosing your high end?
Well, I was just simply using #42 plain enamel magnet wire. I put as many turns as I could satisfactorily fill the space available. And that’s where we stopped right there.
The pickups were designed using heavier strings than today.
The pickups were designed using heavier strings with the high E being a .012 gauge. and now they use .008 which moves the magnetic field much less. They just can’t generate enough energy with that size string. Some players say “my pickups are weak.” If they would only use a heavier string that the pickup was designed for they wouldn’t have any problem. I sometimes wonder if unconsciously if guys who are playing and bending their notes aren’t trying to get the string into tune that don’t have it quite in tune. Unconsciously I think their ears ought to slide a little bit higher in pitch. I’ve hear musicians talking about things that are just bothering the hell out of them – complaining and so forth – and I’d listen and listen and I couldn’t hear. At the same time I could hear things in there that were bothering the hell out of me and they’d pay no attention to them. I hear something they don’t and they hear something I don’t. What are you going to do?
We were talking earlier about how many turns were used to – whatever could fill up the bobbin.
Whatever would fill up the bobbin nicely. In manufacturing, normally when you are winding by hand the bobbin fills a little faster than if you have a traverse there that lays them in nice and smooth. In other words they can get a little more in than you can get by hand unless you are very careful about your winding, which is a little difficult to do. People are lazy – you know, you try to keep it going as fast as you can so the job doesn’t take quite so long. Where it builds on one side, and you have to crowd it over here and hope that it doesn’t get squeezed on.
The wire used then was 42 AWG?
42 plain enamel.
Would the plain enamel be a single or heavy build?
I think it was just a single coating.
Have you looked at the tolerance allowances that the 42 AWG magnet wire can have?
Yes. .0025” to .0029” (thousands). I don’t think that at that time they had a thin or thick insulation. I don’t recall. I can remember seeing wire that was double and DCC – double cotton covered. When we had plain enameled I don’t think that we had the thin and thick enamel covering. My recollection is that it was just plain enamel. And then I think possibly later on they were getting so much variation the manufacturers were getting a little more critical so they would ask either if I can accept the wire a little thin and the coating is a little thinner than what we call minimal. The first thing you know the manufacturer he would have a whole lot of one and not so much of the other, so another guy would accept this range and not the other range, so I kind of think they split it up that way. I could be wrong. Maybe they’ve always had two layers or thickness available that you could buy. Since I wasn’t doing the buying, I was merely using whatever they’d get out of the stock room.
Would they just use one supplier?
That would vary, I supposed as to then they started bidding with different suppliers. Now I know that we’ve used Essex wire, we’ve used Hudson, oh I’d say most of the major suppliers of magnet wire they’ve used.
Did you ever use any other types of insulation or was it just mainly all enamel?
Back then all enamel and now they’re using a polyurethane insulation. I’ve used polyurethane on pickups recently when I was working at Fender and I don’t see any particular difference. The major difference I see is sometimes if you did a little soldering and got things a little bit too hot, it would melt, because the big reason for using that is speed in production so they don’t have to take the enamel off first. In fact Leo Fender never used to take the enamel of the wire. They would wind the coils and rub the soldering iron across the eyelet to break through the insulation. And that is one thing that they never did at Gibson. We’d always use a little piece of sandpaper, wipe it a couple of times and solder to it. We didn’t try to burn through the insulation. With the early humbuckers they always started the lead wire from inside the coil, they soldered the small, I guess 30 gauge wire to the magnet wire and extend it through the square hole on the bottom end of the bobbin.
Did you ever get into using aluminum or silver magnet wire? Economically it wouldn’t be too feasible.
No. Since you had to have special soldering equipment for aluminum and silver magnet wire. Back 10-15 years ago there wasn’t too much around in the way of aluminum solder. Now days they have.
Were the coils when wound on machine wound identical? Two bobbins, number of turns, equal traverse and tension?
There was a tension adjustment for each coil. You could have a different tension on one than the other. But normally the girls got so they could feel that. They didn’t use meters like they do today to measure, because those girls got so they could just sort of lift up on the wire and feel it pulling through their hands and tell the tension. And of course if there was too great a difference you could immediately see it because a loose tension, the bobbin would fill up in a hurry and couldn’t get the turns on. Then if you had a break, sometimes they couldn’t stop that machine in time, before too many, they didn’t notice it – one coil would break, well they’d try to stop the machines so they could make the connection there and splice into it and go on. Because they just strip the ends, wool them together, solder it, fold it over, put a little piece of tape around it, so it wouldn’t touch any of the others. Because whenever you solder like that there might be a little sharp point of solder that would break through the additional insulation. Lay a little wrapped tape, just fold it around there to cover up the point and start it up and again and get going. So you could have a coil that might have 50 or 100 less turns, depends how quickly you stop the machine.
We talked about the addition of adjustable poles pieces; would that change the sound any, the magnetic field disbursed through the bobbin?
On the humbucker the adjustable pole piece extends out the bottom. If you had a magnet that was quite weak you could absorb some of the energy, depends on how far through that screw was, because it’s going to absorb some of the energy there. But as a rule, with a good magnet there wasn’t too much.
What was the reason for having adjustable pole pieces? Was it for a better balance between string?
Yes, It would give you a better balance but it was also a selling point.
On the “Patent Applied For” bobbins there is a square pin hole with a recessed ring on one end of the bobbin. What is the reason for it?
It was in the mold and I recall it was for ejecting the bobbin. It would help pull the bobbin out of the mold.
Why didn’t they use a round vs. square?
I don’t know for sure, but it was something in the tooling that formed that square hole, as I recall. The square pin hole would keep the bobbin from falling as the bobbin was being pulled out of the mold. I used that hole as an exit for one of the leads. The leads only came out the bottom. We wanted to bring the lead out at one end from each bobbin. The beginning from the adjustable bobbin was soldered to ground and the beginning of the stud bobbin was the hot output. The finish of each bobbins were connected together and insulated with tape. I never saw the tooling they molded the bobbins on. We’d merely give them a drawing and then they’d ask for variation to do certain things that would help them. I’m pretty sure the mold went together this way from the sides. At that pin at that end there turned out to be square for some reason. I didn’t ask for a square hole. I’m sure I asked for just a round hole. But apparently they wanted a square hole for some reason or another. As I recall it was the mold makers request to make a square pin hole.
The newer ones they’re making now don’t have that hole. They have a “T” on top which they say is for winding.
“T” most likely for the top of the bobbin. Making sure they keep the “T” on top when doing assembly.
Were the bobbins made out of celluloid or nylon?
No it was Buterate. It’s not celluloid. The early P-90 and Alnico bobbins were fabricated out of celluloid and acetone. It’s not nylon, nylon I don’t think was very popular back then. The Firebird and Mini-Humbucker bobbins are made from nylon.
We talked about the cream bobbins being used for the humbucker bobbins. There were double cream, black adjustable and cream stud, black stud and cream adjustable, and double black. Why where they made this way?
They just picked the bobbins out of a bin and assembled at random.
How many bobbins may have been run at a time?
I would imagine 5-10 thousand at a time.
There are rumors going around that the black bobbin pickups sound different than the cream bobbin pickups. How can that be possible?
I can’t see that it is. The plastics are the same and if the pole spacing changes, the magnetic field would be slightly different on Byrdland humbucking pickups changing the sound.
The Thunderbird Bass pickup was out in 1963. The bobbin was routed down the center and a bar magnet was inserted. Where did the bobbin come from?
We made steel guitar pickups that were humbucking too. There were some steel guitar pickups and I don’t know if they made thousands, maybe several hundred or something like that. The Thunderbird bas probably used the left over bobbins they had. They were modified steel guitar bobbins and used for the bass pickups. If you see the bobbins you can notice the adjustable pole recess molded into the bobbin.
How do you feel about the price of the “Patent Applied For” humbuckers? In the several hundred dollar category.
Probably back then a pickup was made for about $5.00.
So the bobbins were put in a bin and were just picked out at random. The creams were probably mixed in with the black ones.
Chances are that’s what happened.
How did the mounting ring come about? In the drawing in your patent…
I used the old ES-125 (dog-ear cover) as a start because we didn’t have any mounting ring for this. So this was not acceptable as a mounting ring I felt. Because you notice this there was a slight slope to it – slightly different here and here (neck angle). I designed two different mounting rings. One near the bridge and one near the fingerboard. One near the fingerboard is quite shallow at the front edge; and, I tried to set that so the thing would have the slope of the strings when you were fretted at the last fret. And then the one that was back near the bridge, it had to be held up a little higher so I wanted to bring the pickups up close to the string. Because the closer you can keep the pickup to the string the more output you are going to have. It doesn’t do any good to bring – to put the pickup down and bring the screws up to compensate because you’ve lost – you’ve got to get the pickup as close as you can to the strings.
Because you’re losing your magnetic field?
That’s right, the magnetic field comes up to the stings there and magnetizes the strings. That’s one of the things that most people don’t understand. They figure that string is waving there and cutting the magnetic lines of force. Nuts. That isn’t it. The magnet, all it does is magnetize the string. Now you’ve got a waving magnetic field. And we have a fixed coil with a waving magnetic field to induce voltage. If you want to, take the magnet out. One you’ve magnetized your strings, it will play until the string loses it. Players think the string, the magnetic field from the magnet comes up to the string and by twisting the magnetic flux back and forth that’s what induces the voltage. That’s not what happens. There’s a certain amount of that, but that’s minor. What is happening is you have a magnetic field that is moving back and forth across the coil. And when you move a magnetic field back and forth across the coil you induce voltage. If you move the field up and down it wouldn’t induce any voltage. It’s the motion back and forth across the pickup that does it.
How did you decide on the mounting ring angle?
We took the standard stock guitar and added the humbucking pickup to it and needed it to tick up a little bit to give us some decent appearance so that meant that you had to have the front edge thin, the back end a little thicker to get the slant you wanted on it. I thought originally I was going to have to put two screws on each side to keep the slant the way you want it. But for some reason the pickups tend to take on an angle with the cover there.
Did you have to submit any changes when a player came in?
If a player wanted something else, you talked about it, maybe make a few changes before the product went out. The cover was the only essential change. In other words I wanted it bare to start with. Then they decided they wanted some indication of a pole piece. So I put these rings on my prototype and that was not sufficient so we put adjusting screws on one side.
How did you come about using Alnico magnets?
If I’m not mistaken I think the Oscar Moore pickup had tungsten carbide magnets or some such name as that. In other words what ever as the best magnet available-pre WW II (World War II) Well after WW II Alnico magnets became quite popular. They started using it for the magnets in speakers and things like that. And finally electrodynamics died out and we had the Alnico magnets. And of course everybody was selling speakers, selling Alnico magnets and we found that we could get Alnico magnets fairly reasonable, small in size for the amount of strength and the only thing that you run into with Alnicos was they were cast which means if you wanted to keep a dimension you had to pay the price for grinding the edges. And if you wanted an assembly to fit exactly between those pole pieces, you had to make sure that your dimensions didn’t vary too much. As cast, they ask as much as plus or minus .030” thousands. That means as much as 16th of an inch variation. We didn’t care about the thickness varying that much because one would be a little bit stronger and another a little weaker. You could live that. But the distance across the width had to have ground surfaces. They were ground to dimensions. We tried to hold within plus or minus .005” which is pretty tight.
What is the material and purpose of the bottom plate?
The bottom plate is a non-magnetic material so that you did not detract from the magnet. You wanted the magnet to go through the pole pieces and the pole screw to the strings. That’s the path you wanted the magnetism to follow. That’s why on most of those you’ll find brass screws in the bottom. I didn’t want to detract any from the magnet into those brass screws.
Some pickup manufacturers use steel screw to secure the bobbins to the bottom plate.
If they are willing to accept that loss, well fine. When I designed it, I wanted brass in there. I didn’t want to take away any of the magnetic strength in a useless point.
You like using Nickel Silver for the bottom plate and cover. Yes. The legs on the bottom plate are L-shaped.
You had to have room for a spring so if you are going to adjust up and down – you couldn’t have it come just straight out, there wasn’t room enough for a spring to get any appreciable adjustment up and down. So I brought the legs down so I could get a long enough spring there – so I could adjust up and down.
Did the cover that was nickel silver have a plating?
I think it was nickel silver plating and they started using gold plating – if they don’t plate too heavily, that’s fine. Chances are they are not going to plate to heavily at the cost of gold today.
How thick should the cover be so it works properly?
I just selected a size that was easily drawable. In other words that they could handle easily, drawing without tearing. I would’ve like to have kept it as thin as possible. If you get it too thin you get to many rejects when you’re drawing it. It tears easily.
Does the cover have good shielding properties?
It is good for electrostatic shielding. Removing the cover leaves a hole for electrostatic coupling.
Are the pole pieces soft iron or steel?
They are soft iron pole pieces are plated to keep them from rusting and to have a nice appearance. The little slugs are also soft iron. You have a spacer next to the magnet which the screws go into and is used to help hold the screw in tightly and surround the screw with a magnetic field. It was to make sure you got a magnetic path to the screw as much as possible. Also to have something for the screw to adjust in. If you relied on just plastic, it would wear too easily.
The “Patent Applied For” magnet was 2.5” long.
As I recall I think it was called or #55 magnet. 2.5” long X .5” wide X .125” thick. That was the nominal dimensions. The length could vary +/- 16th inch – wouldn’t matter too much. The width had to be held close to .5” if you wanted to keep your spacing right. And the thickness, that could vary +/- 1/32nd”. You could still put the coil assembly together.
How about the four brass screws? They were used to hold the bobbins in place and to eliminate vibrations?
Yes, in other words everything has to fit tight together or if you have some possible movement of one part vs. another you can get a pickup like a microphone – the coils tend to move or vibrate a little, you can talk into it and hear it out of the amplifier.
Have you heard coils squeal when too close to an amp?
Well the squealing part, that could be electrostatic couplings between the speaker. Sometimes on amplifiers they do not ground one side of the voice coil. When they do that, the voice coil acts like a little radiating antenna and you can get electrostatic coupling into your pickup that may cause a high pitched squealing and quite often we were able to cure that by grounding one side of the voice coil in the amplifier. make sure that one lug of the terminal was grounded to the frame of the speaker. As soon as we tied the frame of the speaker to ground, then that would tend to quiet down in most cases. Now you can still get close enough to them where you’ll even that won’t help you much. But then normally an acoustic electric guitar you’ll get plain acoustic feedback or sound from the speaker will cause a howl. It depends where your tone controls setting, to what frequency you are tending to accentuate as to what frequency you are going to hear where it feeds back. It’s not a very high pitched note, it’s generally lower.
On occasion Fender had feedback problems with microphonics at high volumes and use a wax solution to keep the components from vibrating.
When they assembled the humbucking pickups usually they had to clamp down unit tightly until they soldered it together. That would keep them good and tight. If they didn’t keep it tight you could get that same condition where maybe even the magnet might vibrate a little bit.
On many bobbins the coils are wrapped with the insulation tape. Was that for a certain purpose.
For mechanical protection.
Did they always use the #4 flatback tape? It’s been used for years and was it for a specific reason?
They always used the black paper tape and I think it was probably habit forming and then too, in other words that’s probably what the first tape, commercially, they started using.
It works well.
And it worked well for them. It’s inexpensive and they just keep on using it because it would be just like if they changed the color of the wire, somebody would scream, if they change the color of the tape – Gosh, if when they upped their Fender when they changed the color of the string they were wrapping them with, that was the cause of all the problems, see?
Guitarists say “You’ve got to put that enamel wire on it! Nothing else! ‘Cause it won’t sound the same.”
Well as long as they pay for what they get, give it to them.
Gibson has been using the shielded, cloth braid, 7 strand Lenz wire for a long time.
Is Lenz still making wire?
At this time they still were making it. …Tell me a little bit about what you were doing at Fender.
I left Gibson in 1967. Before I left there they wanted me to take over the service department on amplifiers. So I didn’t like the idea but I took it over. It got to be such a hassle, I said get somebody else. I said “let me back in engineering.” And then I kind of got the feeling at the time that they were not going to build amplifiers too much longer. I got an inkling of a job out here at Fender. So when I quit Gibson, I flew to California and looked the situation over and they met the price I wanted to get. Maybe I didn’t ask enough (laugh), I don’t know. I was happy with what I got. So I took the job and went to work for them. Starting out, I was component evaluation and tested speakers. I never saw so many speakers in one building in all my life. In building 1, that was the first building Leo Fender built. That was full of speakers to be tested. Find good speakers so they would have speakers to replace the ones they were presently using because about that time they were having a heck of a problem with speakers. Back around 1967. That was about the time ceramic magnets became popular. They had all kinds of trouble keeping those magnets on the speakers. They would fall off inside the cabinets on their way to the customer. We had the same trouble back at Gibson. So that was one of the problems. And of course that’s the beginning of the high power. The boys wanted more power, you know, and so they began driving things into distortion, clipping and so forth. Sometimes the speakers let loose and sometimes the guys listened to that and said the speaker rattles when it was just clipping so badly it sounded that way. And you had to determine which was which. And then you got to checking speakers and you found that if you drove them at that level very long some of them would blow. So manufacturers had to start building speakers to handle more power. And that’s where they got these new voice coils with aluminum lining in there to radiate some of the heat. So my job was to test speakers and see what would an acceptable sound and to stand the power. The next thing I got into was the big solid state amplifier. Fender had already started building a set of solid state stuff. Well they’d get it up to the point where they’d start shipping and nothing would stay out in the field. It would come back because it wouldn’t sound right, they just wouldn’t sound like the old tube amplifiers. About 1969 I designed a solid state amplifier for them. They wanted a three-channel. And the specs were – this was for small groups, the bass would play in channel 1, Channel 2 somebody could use one of those oil can reverbs (echo’s), the only thing is the cans are forever leaking. Channel 3 will have tremolo and reverb for the lead guitars. Okay, that meant coming out the back with three foot pedals. I was leery of transistors amplifiers, transistors for some reason or another are always breaking down. Instead of having one big, heavy power output stage, I’ll have two-70 watt outlets. It would have 6 speakers – that was the XFL 2000. We discovered that if a guy bought an amplifier, he was not going to let anyone else plug into it, he wanted all these effects. Well the quickest way was to put jumper cords on the second jack of each channel over to the first jack. Now you were able to play using three foot pedals.
Did you design the humbucking bass pickup for Gibson?
After I built the first bass pickup, it was non-humbucking. If you ever got it near an amplifier you picked up and unduly amount of hum. I figured the humbucking is natural for bass because that’s getting down in the frequencies where 60 cycle hums – you’ve got 60 cycle notes plus 60 cycle natural hum you are going to get a lot of wobble in there.
What are the lines on the magnet? Does that represent the north pole?
Yeah. When they’d magnetize those they’d always mark the same side so that when they put them in a pickup, all the pickups will be the same polarity. Since you had plenty of energy – see this is not the ideal way to place the coil if you want maximum efficiency. This one here works and there’s enough turns on that thing – it seems like 20,000 turns on each coil or something like that. It worked pretty well. Of course one of the requirements of this is that it had to fit in the space that the old non-humbucking coils – so that was one of the designs and configurations I had to stay with. The covering held the pickup in place and there was some padding underneath there too.
Where all the parts manufactured outside or in-house?
No, a guy by the name of Watkins, as I recall, Watkins machine shop I think made a lot of the pickup parts. He was out of Kalamazoo and made most of the parts like the bottom plate. I think the covers were made by some place down in Ohio, as I recall. HPI made the bobbins but Watkins made the unit base and pole pieces. The poles in the humbucking bass pickup would have to be removed before the plate inside could slide through the coils. It was a lot of fun making this type of humbucking.
What do you think about the Gibson Melody Maker pickup?
It was a little inexpensive pickup that Gibson made. They were great pickups and were really good. Like some of the higher priced pickups, I think the ones that are simpler sounded pretty good compared. You see they got by without having an adjustment screw and it worked very well. They used this not only on Spanish guitars but they used them on some of the steel guitars. Little 6 string lap steels.
Did the magnets come from Indiana General back then?
Oh, I think they got some – G.E. had a magnet plant around Midland, Michigan – somewhere up in that area. I think they supplied them for awhile and down in Indiana – Indiana General. Then there’s another company that I can’t recall that we got some from. I think Gibson shopped around-when they got down low in magnets they shopped around with the different suppliers – whoever could supply and make deliveries at the time that they needed them and had the best price were the one they got them from. Because Alnico at the time was getting pretty common – everybody could make it and had the facilities.
Do you like reading about magnets?
I’m still interested in magnetic systems. While in the Navy they asked me what I wanted to do with my life. Of course I had to include my own statement and I said that “I wanted to make the most efficient electromagnetic device possible.” And whether I accomplished it or not I don’t know.
Do you think you’ll ever pickup up your guitar and do some playing?
I’ve got several course books. I’ve got a guitar in there, and electric guitar that I made – it’s got a doubler, dividers, automatic wah wah, fuzz and you can play chords with the fuzz on it and play chords with the divider on it.
Does most of the hum come from transformers producing a magnetic field?
Magnetic fields from transformers or if there’s a motor running in the area, magnetic fields will come from that.
Do you still have a coil machine to work with?
Yeah, I have a coil winder stuck back in the corner. …Earlier you asked me the question and I thought about it. Somewhere I have some notes on the first ideas on electric guitar pickups – the humbucking coils. I think it started out back around 1954, or it could have been 1955. Ted McCarty wanted a new pickup. I said instead of just a new pickup why don’t I make some improved pickup, something that will do something that the industry needs, which is get rid of the darn hum whenever you got close to an amplifier.
The rest is history. Here are a few more of Seth’s patents: S.E. Lover: Metallic Stringed Musical Instrument. Filed Jan. 9, 1957, Patented Dec. 25, 1962, #3,069,954. Ted McCarty & S.E. Lover: Patented Aug. 4, 1959, #2,897,709, Russell Zick (Hughes Plastic).