Noiseless Pickup designs

[Spence]

Well we're all familiar with Kinmans, fender noiseless and the like. I just find there's something lacking with them. I can't put my finger on what's missing but equally, I can't quite understand why people trip over themselves to buy noiseless pickups. My philosophy when recording is to let the engineers sort out noises. When playing live there are so many things creating 60 cycle hum that I couldn't care less so long as I'm louder than it.

But here's the thing...I road tested a set of Kinman's a little while ago and they were slightly noisy. So not noiseless then. With that in mind should we be designing alternatives but calling them 'quieter' pickups?

I have a design of my own on paper with component prototype parts waiting to go. Not sure if I can be bothered though. The average punter will still choose Kinmans, except that my version may be very quiet and still fit inside a standard strat cover.....

[Possum]

the guys who want noiseless pickups are the shred metal guys if they're using a strat that is, and fusion jazz guys. These guys all play really loud and are such wussies they can't stand noisy pickups. They also tend use alot of effects trying to add back some life into the tones. You would think with my connections with Shrapnel Records that I'd have them lined up wanting my pickups, NOT. They want noiseless and DiMarzio and Duncan both have signed contracts with them all mostly. I went through a stage like that a long time ago, had EMGs and Lawrences, needed a pedal to get any kind of tone out of them and at the end of the day went back to noisy pickups because they just sound way damn better. Even after working and working on humbuckers trying to get some life out of them I eventually pull out one of my P90 guitars and breathe a big sigh of relief, there's just no match for a noisy single coil P90 :-) For me too, its kinda the same thing with amps. I had a Hot Rod 4x10 Deluxe with the channel switching pedal and my blues junior. Well, at the end of THAT day you just cannot beat the tone of an old handwired Fender amp cranked up with nothing between the guitar and the amp but a cable. Does that make me old fashioned? Hope so :-)

[mac1amps]

I'm certainly with you when it comes to the "purist" sound of non-hum cancelling [single coil style] P.U.'s, as well as non-master volume amps "cranked" to get a true power tube break-up. With that said, I can also understand many pro calibre players insisting on using "noiseless" P.U.'s, at least in a typical live performance scenario (I'm NOT talking about Metal-Head Shredders either). It tends to get much noisier in live performance situations due to the interference of light systems, not to mention the fact that many "clubs" have horrendous electrical wiring which only adds to the obnoxious noise levels. Add ANY effects to the equation and you have some overbearing 60 cycle. In a recording environment, it is usually MUCH easier to get around these obstacles, but not so much at gigs.....I'm also a big fan of P-90's. A few years ago I bought a P-90 "Gold Top" (a guitar I've always wanted to own), only to find that it had P-100's ("stacked" for hum cancelling). I quickly bought/installed a set of real P-90's. AHHHHHH! MUch better, even with a little 60 cycle "thrown in".

[corduroyew]

Why not make a separate pickup that is hidden away somewhere in the guitar. Put a switch on it so you can turn it on and off. Then when you are in a situation were the hum is unbearable you can flip a switch and turn the hum off but when hum isn't a problem and you just want to sound good then let it hum.

[David Schwab]

Single coils don't sound good because of the hum, they just sound better than the stacked pickups, because the stacks seem to lack something. After all, humbuckers sound fine, but they sound different, and it's because of their noise canceling setup.

I recently made two stacked pickups. One was a Tele bridge pickup. I was replacing a Lawrence pickup. The other two Lawrence pickups in the guitar sound fine, they are the old original pickups, but the bridge pickup was one of the ones Stew-mac used to sell, and it sounded weaker.

So I decided to try making a stacked pickup. There's several ways to make them, but I used the Duncan style, where the magnets go all the way through both coils. I had a set of Duncans in a strat once, and they sounded very good.

I wanted a louder pickup, so I wound it as hot as I could with 43 ga wire, which was about 6,500 turns on each coil.

With the two coils wired in non hum canceling mode, the pickup is very hot, and has a great P-90 sort of tone, just a bit brighter. It doesn't hum that much either.

In hum canceling mode, the pickup is very bright, and has a glassy top end. It is very Tele sounding, and the output about matches that of the Lawrence pickups. It doesn't have as much low end as in non hum canceling mode, but it's not bad. It's also lacking in mids, compared to the over wound sound of the non hum canceling mode. I was surprised how extended the high end was for that amount of wire I wound on it.

It ended up sounding a lot like a Tele, but with no hum. But that wasn't what I was going for!

This made me realize why the commercial stacks have so much wire wound on them. The noise cancelation also seems to cancel low end, as you would expect two coils wired out of phase. So the work around is to wind the thing much hotter, to restore the mids and bottom, and to take some highs off... but then it doesn't sound like a single coil either.

I think this is why the Barden style dual rail pickups have become so popular lately. They have a fuller tone.

An alternative is to do a true dummy coil the way Alembic does it. The problem with hum canceling coils is either they pick up the strings, and that changes the tone through frequency cancelation, or you have them in a location with no magnets where they don't pick up the strings, but then they load down the pickups.

By using active circuitry, you can cancel the hum without canceling some of the single coil's frequencies, but then you are starting with a different tone again. I think if you could load the coils to sound like passive pickups, that might work. It works pretty good with EMG single coils. I think the reason they don't sound quite like "real" single coils is actually due to their use of "tone modeling" which I think gives the pickups a plastic tone.

Ideally having a true single coil tone without the hum would be the way to go. As long as the tone was there, I don't think we'd miss the hum. But one seems to negate the other.

When I get a chance I'd record some sound clips of the Tele.

Happy New Year everyone!

[Spence]

It puzzles me that a stacked design can work at all. After all, the second coil is usually so far from the strings that the magnetic field of each pole will hardly create a current in the second coil. The types that use long magnets common to both coils must be choking themselves at the point where the two coils butt against each other.
Fender's noiseless coils use Smarium cobalt magnets in this manner with a thick steel plate between each coil bobbin. They weigh in at around 12 K Dcr which gives them the power needed to work.
I still believe that if a stacked 'single' can work then it can be made to work better than they currently do and be made to fit under a standard cover.

[David Schwab]

Originally Posted by Spence

It puzzles me that a stacked design can work at all. After all, the second coil is usually so far from the strings that the magnetic field of each pole will hardly create a current in the second coil.

In the type of stack where the bottom coil has no magnets, such as by DiMarzio, you don't want the bottom coil to pick up the strings at all. Just the hum. That's also why you see shields between the coils, to shield the bottom coil from the magnetic field..

Originally Posted by Spence

The types that use long magnets common to both coils must be choking themselves at the point where the two coils butt against each other.

Well since the magnet runs through them, they are just two parts of one big coil, with a spacer between. My pickup used a steel blade with two ceramic magnets on the bottom, touching the blade like on a P-90.

If you listen to each coil separately, the top coil sounds like a regular single coil, while the bottom coil has very mellow tone, with less top end. This is likely because it is farther from the strings.

But think of a tall single coil... the bottom half of the winding is also father away from the strings. Just as a fat squat coil has the outer wraps farther away from the magnets.

I think having the bottom coil sound different is probably a good thing... just as mismatching coils on a humbucker should avoid cancelations.

Next I'm going to try mismatching the coils on the stack and see what I get.

Originally Posted by Spence

Fender's noiseless coils use Smarium cobalt magnets in this manner with a thick steel plate between each coil bobbin. They weigh in at around 12 K Dcr which gives them the power needed to work.

Bill Lawrence designed those pickups. That's not as much as the DiMarzios, which are like 24K... at least the one I had. It had a bottom coil with no magnets or slugs, and a metal U shaped shield under the top coil.

Originally Posted by Spence

I still believe that if a stacked 'single' can work then it can be made to work better than they currently do and be made to fit under a standard cover.

It's a tricky thing. Lawrence is probably using very thin wire. His sidewinders sounded very good, but are a bit on the mellow side.

[Possum]

well you are all forgetting the Suhr dummy coil thing that was real similar to what Joe Gwinn came up with a couple years back. A large low turn coil mounted on the back of the guitar, with some kind of tuning system to tweak the cancellation. This is probably the absolute best way to kill hum and not destroy your single coil tone. There is a patent for a bucker sized pickup that used a low turn outer coil away from the magnets to kill hum but my experiments kind of along the same lines didn't work real well and that patent talks about hi-fi tone if I remember. I don't think that pickup was ever manufactured probably because no one liked how it sounded........

[David Schwab]

Oh I didn't forget about the Suhr system. It's kind of hard to do something similar with it being patented and all. Another person who came up with an idea like this was Rick Turner. He mentioned it in a discussion about dummy coils over at MIMF, and did so quite a while before the Suhr system was patented. The sound clips of the Suhr dummy coil I have heard sound great.

[Joe Gwinn]

Originally Posted by Possum

well you are all forgetting the Suhr dummy coil thing that was real similar to what Joe Gwinn came up with a couple years back. A large low turn coil mounted on the back of the guitar, with some kind of tuning system to tweak the cancellation. This is probably the absolute best way to kill hum and not destroy your single coil tone.

I didn't invent it - it's a very old idea. I had forgotten Suhr. While googling for something else (in October 2006), I stumbled upon a perfect bit of prior art on the matter of using dummy coils for humbucking, something that anticipates US application 20050204905 (to Chilliachki):

"Air-core induction-coil magnetometer design", Kari-Pekka Estola and Jaakko Malmivuo, J. Phys. E: Sci. Instrum., Vol. 15, 1982.

Section 4.3 is the key:

"4.3. Differential magnetometer construction
Biomagnetic signals are often embedded in environmental magnetic noise. We have adopted two different methods to overcome this inconvenience. Firstly, the measurements have been carried out in an aluminium eddy-current shield and, secondly, we have constructed an asymmetric first-order gradiometer. The second coil has 4.5 times the diameter and (1/4.5)^2 of the turns compared with the primary coil in order to obtain the same effective area. Because of the big difference in the coil radius the coils can be placed on the same level. The second coil decreases the intrinsic signal-to-noise ratio by a factor of 0.2 dB but it rejects the existing magnetic noise by some 50 dB."

So, there are two coils, one 4.5 times larger than the other, with turns count of the smaller being 4.5^2= 20.25 times larger than that of the larger. That's my area-turns product. The smaller coil is the pickup coil, while the larger is the dummy.

The authors, in 1982, speak of this as commonplace, not claiming discovery.

There is a patent for a bucker sized pickup that used a low turn outer coil away from the magnets to kill hum but my experiments kind of along the same lines didn't work real well and that patent talks about hi-fi tone if I remember. I don't think that pickup was ever manufactured probably because no one liked how it sounded........

I think that the coils (inner and outer) are too close together, and so were not able to keep out of each others' way.

[ken]

Many 1930's U.S. made ACpowered radios with large electrodynamic "field coil"
speakers used a 'humbucking' dummy coil winding of one or two turns in their fields. When I read of the Suhr hum system I couldn't help thinking of it.

Ken

[David Schwab]

Originally Posted by Joe Gwinn

I didn't invent it - it's a very old idea. I had forgotten Suhr. While googling for something else (in October 2006), I stumbled upon a perfect bit of prior art on the matter of using dummy coils for humbucking, something that anticipates US application 20050204905 (to Chilliachki):

Rick Tuner was talking about dummy coils on the MIMF forum, since he had designed a system like that when he worked at Alembic, and mentioned the same thing... a large area low impedance coil which wouldn't impact the tone too much for passive pickups. His comments where quite a bit before the Chilliachki application.

I have the post at work. I wouldn't be surprised if Chilliachki read Turner's post.

[Spence]

I suspect the fine tune resitors on the Suhr system are for the purpose of matchine the DCR of each pickup.

But that's a system outside the confines of a standard single coil pickup cover.
That's the challenge. Now I have an idea which utilizes something that I'm sure no one has done before. I'm not bothered about patents, I really don't care because someone, somewhere will cheat on me anyway. So if it works I'll let you all know.

[Sweetfinger]

Originally Posted by Possum

the guys who want noiseless pickups are the shred metal guys if they're using a strat that is, and fusion jazz guys. These guys all play really loud and are such wussies they can't stand noisy pickups. They also tend use alot of effects trying to add back some life into the tones.

You shouldn't make broad generalizations like that. Its like saying all Brits have bad teeth, or all Asians are good at math. I don't much care for shred metal, or fusion, but I REALLY HATE HUM! I can't have it, and mostly I play moderate level blues. That's the reason I've gotten pretty good at installing dummy coils. Players who want noiseless pickups come from the whole spectrum- country, jazz, blues, rock, punk, reggae, etc. Its just another piece of their overall tone preference. I've seen many otherwise fine players do a whole set out of tune and seem to not care one bit... I prefer my guitars tuned, but I doubt that I would be lambasted as a "wussy who can't stand a little sour note here and there".

The problem is that for people who are very sensitive to the subtleties of single coil tones, there hasn't been a simple hum-cancelling design that fits in the same space as a regular pickup and retains the same response. The newest crop of designs is MUCH better than even ten years ago, but not quite there. I don't think that two stacked coils will EVER get much closer than they are right now and side-by-side or rail pickups just don't do it either. There probably is a design that's been done that really nails it, but is probably way too expensive or impractical to be of commercial use. I've been thinking of a design that should work in theory, but I haven't had the time or money to work on. I've never seen another design like it, or read any references to anything like it. I should probably patent the intellectual property and sell it to someone with the resources. I just want a P-90 in the bridge that doesn't hum....is that too much to ask?

[Possum]

Well I wasnt saying that ALL players who dislike hum are shredders or fusion guys, or else I would have to put myself in that group back ten years ago or so. What I was saying is that fusion and shred guys just plain don't play single coils with few exceptions. Even alot of jazz guys who's idols are old time jazz guys mostly use humbuckers; they forget that most of those old killer jazz players used P90s and Charlie Christian blade type pickups, to me those tones sounded better back then. Even Scott Henderson who has recorded with a real strat at one time or another is endorsing the Suhr product now and loves it. I know alot of these guys personally as I have done album design for them and since getting into making pickups some time ago, none of them have been interested in my work because I don't make noiseless pickups, plain and simple.

There is technique involved in playing noisy pickups, watch a Hendrix video some time, you rarely hear alot of buzz. If your pickups hum loudly turn them off when you're not playing :-) yes some of them have gotten better, Kinman makes decent ones, but I've also made alot of pickups for guys telling me they are tired of sterile noiseless tone from them. I played noiseless pickups for about five years, then one day picked up a friend's cheap strat at band practice and didn't want to give it back to him because single coils are just way richer sounding.....

[Sweetfinger]

If you're playing blues and your phrasing has spots where you don't play, letting the listener 'breathe', there's that dang hum! Ever play a gig where the bar left the jukebox or TV on during your set? Nothing ruins 'All Your Love' by Magic Sam like the lilting strains of Foghat slowly riding over it For me, that's what hum is like,..might as well just set an a.m. radio on top of your amp tuned to Limbaugh.

The only hum cancelling method that seems to work well and isn't terribly complicated is the dummy coil in series, away from the pickup. That's my go-to cure-all. IMO when done nicely, It retains about 98 - 99% of the single coil mojo. You have to have REALLY good ears to hear the difference, where I would put the best of the commercial stack type pups at 90%. You've GOT to get that other coil away from the strings and magnetic field. The more 'art' than science part is that the dummy coil only works really well with narrow coils with moderate turns, i.e. regular garden variety strat style pups. The fatter the coil, and the more turns, the harder it is to get the hum cancelled. On P-90's I have to settle for a bit of residual hum. Pickups with weirdo designs like Gretsch Hi-Lo trons are also tricky.

BTW I actually like the sound of P-100's in certain applications. Send them to me! I will dispose of them properly

[Spence]

[QUOTE=Sweetfinger;10088]I don't think that two stacked coils will EVER get much closer than they are right now and side-by-side or rail pickups just don't do it either. There probably is a design that's been done that really nails it, but is probably way too expensive or impractical to be of commercial use. QUOTE]

If, and I mean if, my design works it will fit inside a regular strat cover, sound just like a single coil and be cheap, noise-free and stacked. Gotta think outside of the box sometimes.

[Joe Gwinn]

Originally Posted by Spence

I suspect the fine-tune resistors on the Suhr system are for the purpose of matching the DCR of each pickup.

Not really. DCR tells you very little about the voltage induced by the humfield. Only the area-turns parameter affects voltage.

Instead, the large coil is loaded by the 10Kohm pot and 10K tone control so the large coil will produce exactly the same voltage (at both 60Hz and at the first few harmonics of 60 Hz) as does the pickup coil.

The DCR of the large coil does matter in that the lower the DCR, the lower resistance of the 10K pots must be to have any effect. But changing the wire size of the large coil has no effect on induced voltage.

The circuit diagram is given in Figure 5 of US application 20050204905, and the operation of the circuit is described in paragraph 0048 on page 3 of the text.

[Possum]

well yer either a hummer or yer not :-) Yes I've played on a small bar stage and on the other side of the stage wall was a huge bank of video poker machines and I'm playing P90s. I don't think audience notice things like hum realisitcally, the bar noise and drums usually mask it out, its not often you get a guitar solo where everyone is really quiet behind you either. Even on that stage though if I pointed in one direction alot of hum went away and I would always shut it off between songs. I can see in a recording environment hum could be a problem but you also have alot more control over that stuff in a studio too. I had a guy do a record with my low wind custom strat pickups and his tech was able to use some kind of star grounding thing to an aluminum guard plate and some trick they wouldn't tell me about that got rid of vitually all hum without killing any tone. It can be done. P90s though are a problem, I know Gibson did a guitar with a dummy coil hidden inside but I knew a guy at the jam that had one and when the hum went away so did the tone :-)

[mick]

" and be cheap, noise-free and stacked. "


Wow , it sounds like the ideal woman...

[Spence]

Nice one Mick. Personally I'd prefer a perfect size 10. You know, just tall enough to do the honours with a flat head to rest my beer on.

Apart from that, I recently did a small gig where my strat started humming a bit. 'Annoyed' was not the word as my strat's so bloody quiet normally. Turned out to be caused by some shit the resident DJ was pissing around with.

BTW, check my new 21 Y O girly singer!

100_2204.JPG

Amazing voice apart from everything else....