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Or even desirable?
There seems to be a gerat deal of variations in pick-ups with a huge market for boutique designs in the aftermarket .
Including those of the same type. Bareknuckle for example has many different "humbuckers" with varying degrees fo output and resonant frequencies.
Take the humbucker for example. The differences in the variations involve the resonant frequency.
The object to design a pick-up variable peak resonant frequency control(passive)we don't want to have to change batteries.
Maybe something with a small screw adjustment on the side of the cover.
Players could adjust the resonance to a position they prefer using their ears.
Antoher advantage would be when using different amplifiers, the guitar could adjust to make a more preferred response.
I was thinking of something like the use of a small adjustable 3rd coil for example, in the dual coil
humbucking pick-up, might work or using multiple taps off the coil at various locations.
for example all three strat pickups in one and using a micro switch select the position.
I have some old pickups which I have been experimenting with.
Anyone else delved into the magical electric world of pickup peak resonance?

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

Pretty interesting Wiiliam!
I'm amazed at the different sounds different humbuckers have.
Maybe you could play with one of the coils in a humbucker?
Maybe put a pan pot between the two coils?
I'm interested in your experiments!
Dan

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One such circuit which is interesting is the Varitone circuit used by Gibson and Epiphone in the BB King Lucille guitars.
It is made up of a resonant circuit or a 'tuned circuit".
It uses capacitors and resistors in series with an inductor.
The use of the inductor is vital in getting the Varitone to work effectivley.
What about visa versa?
Gibson calls for a 1.5 Henry inductor which is quite substantial.
In constructing and installing Varitone circuits in guitars I discovered by accident
that using smaller value inductors are sufficient to give the Varitone effect.
Granted most feel that there is only one varitone position that sounds good )

I have found the Varitone circuit can be a great tool for isolating a guitars sound in the mix.
A useful tool.
This has lead to further investigations in this area.
In using small variable inductor or RF Coils ranging from in the hundreds of uH's - the type used in Ham Radios. The concept is to remove the use of the resistors which I am lead to believe are there just to prevent switch "pop".

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

Were those old low impedance pickups in Les Paul Recordings, Les Paul Triumphs, and L-5 solidbodys active or passive? I don't think there was a battery in them way back in the Stone Age.

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"Act your age, not your shoe size" - Prince

Hi Chris, thanks for the interest. Yes, I believe they were passive.
The idea of what I am trying to achieve is not quite the same.
Basically I am trying to build a pickup which has a variable peak resonant frequency which is what gives a pickup its character.
In the end the idea of having a small screw on the side of the pickup cover which when turned tkes that pickup from something like a vintage PAF to something more contemporary like the popular Seympur Duncan JB.
So in the end one would have a pickup which, when using Duncans as an example, could be adjusted right across the model spectrum from the '59, Pearly gates, JB etc. As many different variations as possible with the simple twist of a screw.
Of course precision perfection is out of the question as there are many more things involved in the nature of the sound the pickup produces, such as magnet composition and wire type and so on but I think that something close may be a worthwhile pursuit, if not only for practical reasons but for interest sake.
The basic pickup design has not really evolved very much other than just more variations of the same.
I though alumitones might be a good platform as there is more room to add the components but I don't really wish to $pend.
so I am using cheapo pickups to start.
Here is an early proto type using the coils from 2 P 90's as a platform and the variable inductor between them.
You can see the inductor is small about and there are smaller ones available which might be incorporated into a pickups case.
One idea may be to have a "multi-tapped pickup" I am considering building a winding machine. that way you could wind a pickup with 2 taps for example and have a selector switch for 3 different numbers of turns-similar to a multi tap transformer.

thanks to google for this found on another site:

"First off, you will not increase the resonant frequency of the pickup unless you start to pull turns of wire off the coil. Any capacitor scheme will only create a 6 db/octave smooth roll off, no resonance there. The first thing that will do is remove the pickup's resonant peak. Just the use of a passive volume/tone control will pull off that peak and reduce bandwidth.

To create a variable resonant peak circuit, you need to go active. Alembic created this design back in the mid 70's. You use a opamp preamp with a high input impedance, 1 meg or more. This protects the bandwidth of the pickup as any passive scheme will lower it significantly. Then a active filter circuit is used. A sallen-key 2 pole low pass filter was used in the Alembic circuits, with a 3 way switch for resonance. One position is flat, one with a small peak, the third with a larger peak. A dual 100k reverse log pot is used for tuning the frequency. It sweeped from 12 k down to 500 hz. The idea was when combined with a wideband relatively flat pickup the user could tune the resonance and bandwidth to emulate other pickups on the market.

Look at Don Lancaster's Opamp Filter Cookbook for low pass filter examples including the sallen key and multiple feedback filters.

Jim Williams
Audio Upgrades "

Oh well its fun messing with old pickups.
There are so many excellent ones out there these days there is not much else do with the old ones from the junk box.

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

Interesting thoughts.
I think your best bet is a multi tap wound pickup,
like you said.
I can't think of a way to increase or decrease resistance short of more or less wire.
I like both standard wound, and over wound,
standard wound sounding more musical,
over wound more full and fat.
Keep working on it,
you might come across something cool!

I installed one of them Alumitone Deathbuckers. That's a whole-nuther type of pickup.
The pickup sound is totally flat, no color or distinctive resonant frequency.
It's a perfect pickup to run through distortion and effect pedals.
Run through a clean channel, it's quite bland.
It might be cool to run it through some varitone type circuits.

I'm not much of a pedal guy, I play through a nine-tube Carvin half stack with real tube distortion.
I've made some mods to the amp, my next mod will be replacing the volume pots or adding resistors to have better control at the lower end. Knob at 1 is quiet, at 2 the windows shake.
I'm afraid to try past 2.

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thanks for the encouragement Alan. Ya I think the muti tap thing is a good exploration. Although its hard to say how having the unused wire sitting there will behave in regards to noise.
perhaps if it was ground when not in use.
Anyhow I'm sure the way tech is going in this day and age it will most likely happen.
Just think how wonderful it will be to have a digitally emulated pickup similar to a variaxe only you can use your own guitar!
;-(
Its fun messing with these things. I have found that the Bareknuckle Nailbomb in the bridge was great for use in my DIY 6aq5 champ. sounded great. but I moved the guitar and that p/u went with it...oh well.
Learn by doing...I guess.

I tried the alumitone strat set when they first came out; in a beautiful white with tortoise guard squire strat
they were so clean I wanted to wear a tux and play Cole Porter tunes.
Its just nice to see someone try something a bit different. At first I thought them a little odd but after that, I think the Alumitone is here to stay.

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

Might want to check out Dialtone Pickups. http://www.dialtonepickups.com/

Hey, those dialtones look pretty cool.
Not as expensive as I thought they'd be.
Dan, you might want to try a smaller amp.
My favorite ever was a Fender Princeton blackface.
Sold it, and really don't regret it.
Those smaller 12 watt amps sound amazing,
because you can turn it to 10,
and be in the same room it is.
Nothing else like hearing the power tubes distorting!
Old Fender Champs sound really good too!
Make sure it has tube rectification tho!
I never had volume problems playing small clubs and wineries with either one.
A!

Watched 6 vids or so.... Sounds like it has a Morley Wah in it. Frank Zappa might have liked it. I don't see the point.

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"Act your age, not your shoe size" - Prince

Zappas cool..."Music is Best"


dialtones...ha ha sound they work pretty good once you get over the antiquated rock music noise and actually get to the review examples.

big problem though as they are ACTIVE w a 9volt batter- so that just doesn't do it for me.
Well one point of having a specialized option may be when creating music in a recording studio.
Sometimes thick mixes with lots going on it can be especially hard to find a notch to put the guitar noise in.
Its nice to have lots of colors when creating music.
Something like this might make it easier. I can see it for live use too, maybe when playing jazz fusion or something with a lot of keyboards and analog synths in it.

I'm still going to make something just for fun. but you'll have to tweak mine with a small screw-driver-in the side of the case.
having the control right on the p/u doesn't work for me Artistacally its too much avaiability.
I figure a single coil on a hum bucker frame should give enough real estate.

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

I've been doing development work on a low-z active system for the past decade, although it has only really started coming together over the past few years. It has all come down to combining the pieces that people got right with the technology they lacked at the time to make it a reality. The way I see it: if I'm standing on Les Paul's shoulders to see the best solutions, I'm probably getting something right. Since it's a product under development I don't want to give everything away (unless you want to sign a NDA), but I have fully independent control of Gain, Resonance Frequency, Q, and a couple of other tricks. It also allows for options such as mixing humbucker coils for intentional mismatches that can produce desirable effects. In my case I'm willing to go as far as using active circuits that are completely analog but capable of digital control/programming, or switchable modules capable of duplicating the response of any other pickup. I shared too much with a guy who is approaching the same problem but wants to use DSPs, and he already has investors now.

To go totally passive, consider your variables and how to manipulate them. You can't use what isn't there in the first place. Les Paul's Studio model had a resonant peak above 100kHz and DC resistance of about 200 ohms (which means you can plug it directly into a mixing board without loading effects). For use with an amp, the circuit included a microphone matching transformer and those are still readily available. Alumitones are a bit odd in that they use the solid metal frame as the primary side of a transformer, which is fed to a current sensing transformer and finally a matching transformer that also sets the resonant peak and other parameters. You can build one with 10AWG wire and off the shelf parts. I would suggest starting off with pickups that have resonant peaks in the 15kHz to 20kHz range. It's easy to shift frequencies down passively with nothing more than capacitors. Q can be manipulated with loading resistors exactly the same way volume pots can make a pickup too bright or too muffled. Good luck.

thanks to you Hugh Evans...for wishing me luck.
As one who works intuitively and lacks real scientific or electronic knowledge; believe me when I say-
I gonna need it!
thanks for the information and good luck with your project as well.

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

ElectroKraft made one. The magnedyne. Tunable with a trim pot.

Sent from my HTC Desire 626s using Tapatalk

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Another day, another dollar.

Hey thanks...So it's possible then. according to info from googling:

"The Magnedyne pickup includes a built-in passive circuit that effectively changes the pickup’s inductance, resistance and capacitance; the elements that change how a pickup sounds. This is achieved without any active electronics and no need for a battery."

http://www.guitarsite.com/news/gear/electrokraft_releases_magnedyne_adjustable_tone_vintage_style_single_coil_pickup/

Looks as though it didn't sell? I wonder if theyre still doing it.
Maybe they didn't consider Aesthetics and the conservative nature of most guitar players?
Or. many folks just don't think its useful enough or dislike advertising.
I've seen lots of pickups with the "Seymour Duncan" and "Duncan Designed" removed. Pros most likely don't care but unfortunately with the lack of money in the pro music business most probably wouldn't give it a second thought while rich musicians have all the tech magic in the world at they're disposal.
Had a great price point though- 89 bucks...

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

Alan,
My favorite amp was a Fender Musicmaster bass made in the early 70's. 20w.
I drove it with a solid state mic preamp.
Cranked up full blast, it had the sweetest "clean" distortion ever, if that makes any sense.
I put a giant reostat in the speaker lead to dial down the volume.
I had two, they were sold in a garge sale for $20 without my knowledge.
Dan

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Interesting, but I'm having trouble finding anything about how they work. One pot leaves no means for independent control over the key parameters. That's why I arrived at active, and have been referring to my project as "rewinder": it can duplicate the effects of changing the number of turns of wire, the wire awg, internal capacitance, and magnetic field strength.

Thus far nothing has turned up from searching patents, or even checking with people I know from other forums who would gladly dissect and study a $90 pickup.

Since you've mentioned that you don't have much of a technical background I can break down the really important stuff into pretty simple but totally effective terms. Depending on how ready you are to really dive in, it's worth getting a basic digital storage oscilloscope that has a built in signal generator. For pickups I have a handheld DSO 203 Quad from Seeedstudio running custom firmware and a wrote a program for the sole purpose of profiling a pickup within a few minutes. If necessary I can even turn volume and tone knobs up all the way, select the pickup I want to study, and then plug in a 1/4" jack directly into the guitar that is hard wired to leads from my scope. If you get one, I would be happy to share my code with you or anyone for that matter. You just select the range of the frequency sweep as well as the number of steps, press start, and when it's all done you'll have frequency and phase angle data that can be studied in any spreadsheet. I'm working to further refine it, but it's proven itself thus far.

Now, back to the original topic. In the simplest of terms all that matters for a passive pickup are:
*Wire AWG
*Number of turns of magnet wire around the bobbin
*Magnet strength
We won't worry about nitpicky stuff such as eddy currents, permeability, etc.

Wire AWG plays a major role in inductance (resistance as a function of frequency, and much more useful than DC resistance), and capacitance. Some people just go with the most readily available and "standard" magnet wire used for pickups. I personally prefer to maintain coil geometry so that the same approximate area under the strings will be as close as possible to the family of pickups I'm replicating. For example, you can fill a Strat bobbin with a few hundred turns of 34awg wire and drop the inductance and capacitance to insanely low values but this applies through a wide range of combinations. Even Amazon has a huge selection of magnet wire aside from the typical 42awg stuff that is normally used... But what you're doing isn't normal, so why worry about getting outside the box?

More turns means a bigger signal, but it also comes at the cost of capacitance. That's exactly the reason overwound pickups can sound muddy. A really great example are Fender's Texas Special pickups. They got to conduct a complete study of SRV's Number One and by all accounts the pickups were just what one would expect for a late 50s/early 60s Fender wind. To anyone seeking a vintage Strat tone, don't be afraid of DC resistance in the 5.5k to low 6k range. They sound fantastic. SRV used long high capacitance cables, but approximating his tone by including a 50' cable with every guitar that uses them wasn't an option (I'm sure marketing played a role here)... So instead, they overwound them to all hell so players who just want that one tone while using a high end 10' cable will probably get what they were looking for. Just don't ask them to deliver any spank or sparkle.

Magnet strength does interact with the coil, but as I said above we might as well start basic and can work up from there. They basically define the Q of the response curve, which is a measure of resonance. Stronger magnets will generally result in a much higher peak at resonance, and weaker varieties will be more mellow. If you want to visualize this: google "2nd Order Low Pass Filter". Fender has actually done a really good job with their vintage sets in terms of matching resonant frequency, but most of them would benefit from about a 20%-40% decrease in strength. Contrary to popular belief: AlNiCo V magnets, which are what Fender tends to use, don't lose much strength over time. After all, does anyone ever complain about the tone Hendrix got with brand new CBS Strats? Unless heated to temperatures that would destroy the guitar and pickups, even pickups from a 54 Strat or PAFs have lost less than 1% of their original strength. It's much more likely that the observed difference in magnetism is the result of modern manufacturing techniques resulting in higher quality magnets

Feel free to shoot me a PM anytime. You're going with a challenging route and I'm curious to see how far you can push it. You might also want to check in on the music electronics forum where their are tons of winders with all levels of expertise. And much like OLF, an overall friendly and helpful bunch.

Thanks very much to Hugh and everyone else. I think Ill just stick to fixing them, or at least attempting to, (for the wire she's very small ). I found it frustrating and annoying.
I was curious why I had never seen such things.
I see that Seymour Duncan has put micro switches on pickup rings now in there product called Double Shot-
I think that may be worthwhile for musicians who like the variety.

http://www.seymourduncan.com/accessory/ ... set-arched

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You just pick up a chord, go twang, and you're got music. -Sid Vicious

Just another part to wear out or break...

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"Act your age, not your shoe size" - Prince

And they cost a whole lot more than push-pull pots.

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sometimes $ just can't be a factor...

neat concept...yeah, all parts wear out...in Physics it's called entropy...either way, I've never likes a push pull pot...have always used switches for tapping of a pickup...not sure of what Duncan is doing but from my own body/brain training I'd prefer to have the switches at the bottom side of the ring (yah, just flip it upside down if possible)...

my first PU mod was on my late 70's Les Paul...put in a Duncan SH-6 in the bridge and used CA to glue a simple switch on the bottom of the pick guard (humbucking/single coil)...long story short, ,my 'baby' (84 Jackson Rhoads Custom) also has an SH-6 with retail wiring and is switched for series/single/parallel...

anywho, nice concept but I must say an old school switch seems so much easier to use...fekk the additional hole or whatever

You are getting into serious mad scientist territory. While I doubt if what you are considering is possible, your idea of multiple coil taps seems to have some validity. Myself, I have pondered that since the original telecaster bridge pickup sent some of the magnetic flux loops through the strings to the bridge saddles then back to the pickup through the steel bridge plate and the steel plate under the pickup, could you put an invention in there with a lever to move magnets to send more or less flux to the bridge? Your post has started me daydreaming of a gadget to physically move a humbucker's magnet to have it be more or less strongly coupled to the polepieces. After all doesn't some famous manufacturer make an "air gap" model humbucker where the magnetism must jump a gap at the bottom of the pickup?
Good luck. Have you studied enough physics to know the concept that magnetism always follows closed loops? Have you read the excellent book titled something like "Pickups...Wires and Magnets and the Guitar Became Electric"?

Well I think the Duncan ring is a cool idea- light, easy to install with no changing of the guitar other than the p/u rings and a few solder joints.
Very small and unassuming - push pull pots are for the most part not so good- Ive never liked them and they can be annoying as well as noisy sometimes.
I like simplicity of it, as most times is always good
-you can still keep the stock wiring in place with all their "grail pots and caps" they love so much.
I guess the only way to really have a whole lot of musical pallet is to have lots of guitars
-Ive swapped a few pickups around always with different results on different guitars even though for the most part the guitars were basically the same construction -solid electrics.

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You just pick up a chord, go twang, and you're got music. -Sid Vicious