I know, I'm crazy, but what about superconducting pups?

[Whiskey_Funeral]

But you literally would not be able to stop a note sustaining until you raised the coil above the temperature at which it stops superconducting. The pickups would literally be unusable. Unless of course you write music that consists of one neverending note of course.

Like if you play in Sunn O)))

 

[SYLrules88]

if you die, can you send me your Krappy Guitar? wait, its left handed...

a few posts in here actually made me laugh. all in all, i know nothing about superconductors, but i love reading about new and interesting ideas. as far as the note sustaining forever, surely you could find a way to alter the flow of liquid nitrogen so the pup could heat up above its critical temp.

good luck with this idea! there's sure to be plenty of nay sayers, but if everyone stopped trying to invent or reinvent something because they were told they were crazy, id be writing this paragraph with a quill and ink.

 

[bishopdante]

Most really powerful laboratory magnets for equipment such as MRI scanners are built using superconducting field coils.

The windings in the design of a superconducting field coil is extremely critical, partly because the forces can be destructive and so few windings are required.

There's also a fair argument that superconducting field coils are unnecessary for guitar pickups, and that a conventional field coil with sufficient current running through it would produce a perfectly strong enough magnetic field to overcome the string tension completely and stick the strings to the pickup, thus preventing a resonant note from forming.

Where superconducting field coils might prove more useful is for the building of speakers, which would allow cones of much greater sizes and weights to be manipulated using a much smaller voice coil and a larger gap for the voice coil to move in. A superconducting speaker might well require no additional suspension, with the diaphragm being held in place entirely with magnetism.

For reference, a bench-top superconducting field coil approximately 15cm in diameter is powerful enough to levitate a garden table.

The limit of power is how much 'leccy can you fit through it before it boils off the coolant. The interesting thing about how superconductors work is that they have no resistance because they actually don't conduct electricity at all, they force it to run magnetically along the surface of the metal.

 

[Rizzo]

Don't want to ruin the party, but just a rational thought: if no one thought about that or actually did that until now, it's probably because it is impossible, unpractical or inefficient.
It's not rocket science after all, so...

 

[Dusty Chalk]

Pfff ^ The world would still be flat, with thinking like that.

Correct me if I'm wrong, but what this will accomplish is to greatly reduce the resistance of the pickup, while leaving the inductance the same, neh?

Honestly, I have no idea what that would do to the sound. (Does anyone?) I guess there's only one way to find out.

Dibs on "superconducting pups" as a band name.

 

[GuitarBizarre]

Guys, you do realise that room temperature superconductors don't exist?

https://en.wikipedia.org/wiki/Room-temperature_superconductor

You'd have to keep the material in question below -135C at all times for this to work.

Also, as mentioned, resistance in pickups isn't actually a contributing factor to the sound - capacitance and inductance are. Capacitance is largely independent of the metal's conductivity.

Finally - There are already a lot of ways for us to very accurately record the position of a string at a given point, with sufficient accuracy and samplerate to far exceed human hearing - we just don't use them because pickups are cheaper to make and work "well enough".

Why go for such a stupidly overwrought system when you could just use one of those?

 

[Dusty Chalk]

Also, as mentioned, resistance in pickups isn't actually a contributing factor to the sound...

Then why is it always listed as one of the specs? There's the whole "overwinding" and "underwinding" thing, so doesn't it contribute to whether it's a high gain pickup or a medium or a vintage gain?

And in answer to your other question: it's an experiment. Personally, I'd do something like a lapsteel, except it wouldn't be in my lap.

 

[GuitarBizarre]

Then why is it always listed as one of the specs? There's the whole "overwinding" and "underwinding" thing, so doesn't it contribute to whether it's a high gain pickup or a medium or a vintage gain?

And in answer to your other question: it's an experiment. Personally, I'd do something like a lapsteel, except it wouldn't be in my lap.

Overwinding and underwinding affect the sound because they increase the capacitance of the pickup, not because they increase it's resistance. If you take a pickup, wire a resistor between it and the output jack, and let rip, you get the same sound but quieter. (Volume pots do exactly this, but they bleed some of the signal to ground, instead of converting it to heat via resistance, which is why they cause high frequency loss as you roll them down - because the HF gets to ground a little faster than the LF)

They do also increase it's output, but that comes at the cost of capacitance. If it didn't, every pickup would be wound to about 40K or something stupid, because there'd be no reason not to just get a stronger output and boost your Signal-to-Noise because of it. In reality, this severely hurts the high frequency response, so pickup manufacturers try and find a happy medium based on the output level needed and the sound desired. Too low, and your pickup's output won't be high enough, and you'll have to add lots of gain and you'll get a lot of noise because of it. Too much, and you'll get a nice black noise-floor but you'll have no top end in the sound.

It's listed as one of the specs because when you wind more wire onto a pickup, you increase its output level - because you'll have more coils of wire in which to induce a voltage when you disturb their magnetic flux. If you measure two identical pickups and get say, 7K and 10K resistance figures, you can assume that the pickup with the 10K reading has more coils of wire on it, and therefore will be louder than the one with 7k. (It will also have curtailed HF response, see below)

There isn't a reliable way to measure a pickups strength of inductance, but it can be inferred, in comparison to other, similar designs, based on the amount of wire in the coils.

That's literally as far as it goes though, and it's important to remember that the output is affected by other factors, like:

• Magnet type - Alnico 1-8, Ceramic, Neodymium, CuNiFe like the old Charlie Christians, etc
• Whether the magnets are the poles - Strat, Tele, Vintage Fender Wide Range Humbucker (Modern ones are PAF style humbuckers under a larger cover), Jaguar etc
• Whether there's a bar magnet underneath some ferrous but non-magnetic poles - PAF, P90, Charlie Christian, etc
• Coil Geometry - Low and flat like a Jazzmaster coil?
• Coil Geometry - Tall and thin like a Strat coil?
• Whether there's a dielectric effect from air gaps or so on (Like Dimarzio "Virtual Vintage" or "Air" Pickups)
• Shape of the polepieces (Rail vs screw vs Hex-Head vs Oversize poles)
• Scatterwound coils, or machine-perfect precision? If you scatterwind, you end up with a larger, less dense coil, which means air gaps and less actual turns around the bobbin - more capacitance for the same size of coil.

Measuring the resistance is just a way of saying "All other things being equal, this pickup will have high/low output because there's more/less wire on it", but that's not why it will also sound different.

It will sound different because having more coils in the same space will result in the pickup having a higher capacitance - and when you increase capacitance in audio signal paths, the end result is a predictable, high frequency rolloff, and a boost in the peak frequency immediately before that rolloff.

More coils = More Capacitance, More Output, Less High Frequencies, and a more drastic peak in the frequency response.

That's literally all resistance figures are good for.

FYI = The reason it gets quoted constantly despite being not that useful in the end, is also the same reason people quote wattage figures for speakers despite having no idea the difference between RMS and Peak Power, or Impedance ratings for those speakers - It's a figure people think they understand based on a constant re-telling of a ridiculous falsehood. But because it's easier to perpetuate that falsehood, than it is to explain to people the reality of the situation, people still do it anyway.

It's a farce, but theres nothing you can do about it but educate yourself.

 

[Rizzo]

Pfff ^ The world would still be flat, with thinking like that.

Didn't get my point. Nevermind
I was just trying to say that not all presumably "innovative" ideas make sense to put in practice or business.
Still, it's good to experiment.

 

[ASoC]

Does anyone ever check post dates before they post in a thread anymore?

 

[leftyguitarjoe]

Holy necrobump batman.

 

[Alberto7]

Idk, I'm glad this got bumped because I'd never seen it before. I've become increasingly interested in electricity, magnetism, circuitry, and circuit materials, and I've been doing soldering workshops, and there's a lot of cool (pun intended) info here that I wouldn't have seen otherwise.

I say someone should do this, if anything because it sounds fun and interesting. Absolutely not practical with any current technologies, but totally fun.

Long technical post

This guy sounds like an engineer. If not, he/she/they should be one.

 

[Dusty Chalk]

Yeah, seriously -- thanks for the lengthy and reasoned response, I actually understood all of it, and appreciate the education.

Does anyone ever check post dates before they post in a thread anymore?

Lollers -- no, apparently I did not.

alm: @ self

So I guess I don't get 'dibs' on the band name? Oh, look, there's already a superconducting pups tribute band...

 

[Nag]

Holy necrobump batman.

Hey, YOU are the one who started this in the first place

 

[Konfyouzd]

... And did anything ever come of this? God forbid we take interest...

 

[Dusty Chalk]

Cool your heels, gents...

Oh, look, I make pun.