How much difference in sound when coil is closer/further from the magnet?

[Marko Ursin]

I'm planning to make an individual coil bass pickup once again. How much difference can I look for when winding the coil directly over the 5mm alnico rod vs when the coil is wound over an 8mm plastic bobbin (inside of which is the same 5mm alnico rod)?
I'm trying to make this one fit in a guitar humbucker size cover, that's why I'm trying to fit the same amount of wire in a smaller diameter coil.
Marko

[David King]

Marko,

It isn't clear to me what you're asking. Doesn't the same magnet fit into the bobbin?
The wire has to go somewhere, either towards a taller, thinner coil or a shorter, fatter one.
If you have a 1.5mm air-gap between the inside of your coil and the outside of the magnet you will end up with less capacitative coupling i.e. If your start lead is Hot and you magnet is grounded you'll gain some treble. However I've always herd (sheep) that air-gaps kill the high end so you'll just have to tell us what happens.
The flux lines have to pass through the coil for the pickup to work.

[FunkyKikuchiyo]

I THINK he's asking about the space between the coil and the slugs/magnets. So, the difference between being wound directly onto magnets versus onto a bobbin, and then once dealing with bobbins the difference in the thickness of the wall.

I haven't done direct experiments so I won't comment on the effects except that I notice the closer it is the more defined the sound seems to be; I just wanted to see if I could help with the language barrier.

[Marko Ursin]

Here's a pic to help my poor explanation. I've made the coils like the one on the left, now I'm planning to make them like the one on the right. The bobbin on the left one is made of acrylic, on the right the end plates are made of acrylic. The grey piece is 5mm Alnico rod, brown is the coil.
I hope this helps to understand my English.
Marko

[peskywinnets]

The recent pickup experimenting I've done, is pretty much a coil wound direct onto a steel blade...the problem is I don't have the other variant to compare against (ie wound around a bobbin, with the blade being inserted into the bobbin afterwards) .....but even if I did, you'd be in the domain of my subjectivity! (& of course it's custom on here to say that everything you make sounds the nuts!)

Best just to slip on your Nike T-Shirt & "just do it"...rather than pontificating about it - things can get pretty heated around here wrt theory!

[Marko Ursin]

I'm going to do this, no doubt about it. I suppose it will work as there is a lot of pickups wound directly over slugs or magnets. I'll let you guys know when done.
Marko

[peskywinnets]

I suppose it will work as there is a lot of pickups wound directly over slugs or magnets.

If you were just wondering whether it'll work or not - I can confirm yes it does (just be extra careful about ensuring your windings don't short to the slugs/rod - perhaps some PTFE tape around them?), if you're wondering whether the outcome sounds better/worse, then that's when you need to decide for yourself!

[Marko Ursin]

If it sounds close the same as the ones I've made so far I'd be happy with it. And if I don't like the sound I'll try something else. With my very, very limited knowledge of pickup making I think there is lot more than just the coil distance from magnet that makes the sound. We'll see (or hear) how this one will turn out.
Marko

[Mark Hammer]

Anything that obliges the turns to be started further away from the magnet itself will automatically make the average circumference of the turns larger/longer. That will affect the inductance. As well, the bigger the circumference, the greater the DCR for the same number of turns. Bigger circumference is not automatically a bad thing, or lead to bad tone. For example, the Fender Jazzmaster pickup has a shallow profile that makes the outer turns have a big circumference. But if you consider that the Jazzmaster has the start of the coil wound up right against the polepieces, there is some treble preserved. Higher DCR is also not intrinsically a bad thing, but unless the electronics that follow the pickup anticipate a higher-impedance load, you can lose some treble. However this is not a case of the "sound" of the pickup being poor, but rather a question of goodness-of-fit between pickup and context.

[Marko Ursin]

So to make it easy for a beginner like me everything has an effect for everything and the "goodness" of the sound is in my ears? Right?
I have recorded the pickup made with acrylic bobbind´s and I'll record the new pickup as well and listen what the differences are.
MArko

[Mark Hammer]

Yes.

Much of what you will see on this forum assumes that the pickup is being used with standard electronics, and that you are trying to make the pickup produce a "classic" tone. It is all good advice, but that does not mean that a different approach to making the coil or space between magnets and coil can not sound good if the electronics are adjusted to suit the pickup.

[Triad]

If you put the wire closer to the magnet you end up with more highs... that's for sure. I know there are tons of theory behind this stuff but hei, I'm more an "action guy" than a student.

[salvarsan]

Think about it like this: the biggest magnetic field variations happen close to the magnet and guitar string. Windings that sit in that spot give the most signal.