Pickup Location Difference?

[NickCormier]

I have a question for you guys..

Im about to make my first guitar, and I was just curious about pickup location on the scale.. Does it really make a huge difference on the placement of them??

I am looking at using 27 frets, but I also want a neck hum... on a 26" scale. So will this be able to work with the neck pickup? I know people make a big deal about 24 frets sounding bad on the neck pickup because the neck pickup is back further...

Anyone care to explain? Thanks

[Sambo]

Right... the 22 vs 24 fret theory goes as follows.

If you have a 22 fret guitar, the pickup is effectively under where they 24th fret would be. Now, this is a harmonic node (as the 12th fret etc are). Now the theory goes that if you place under the 24th fret (ie you have a 22 fret guitar) you loose some of the harmonic qualities as the pickup doesnt pick certain parts of it up. How much of this is true, how much is voodoo is up to you, but they do certainly sound different.

In terms of your 26-27 fret axe. its dooable. PRS did one in their early days, Caparsion make them and i'm sure a few other companies do too. Be aware it will sound different. Obviously, the closer you move the pickup to the bridge, the more like a bridge humbucker it will sound. Think of a strat... the middle pickup is somewhere between the bridge and neck in terms of tone. move it either way, and it will get closer to the sound of the pickup its closer to.

And for what its worth... i prefer the 24fret guitar neck pickup tone to a 22fret one. think it sounds more... rounded and less wooley!

S

[NickCormier]

But for terms of actual position, like hypothetically just say I put the bridge pickup 1mm away from the bridge itself, It wouldnt make a big difference?? Like it would still be audiable, etc..

[unklmickey]

Right... the 22 vs 24 fret theory goes as follows.

If you have a 22 fret guitar, the pickup is effectively under where they 24th fret would be. Now, this is a harmonic node (as the 12th fret etc are). Now the theory goes that if you place under the 24th fret (ie you have a 22 fret guitar) you loose some of the harmonic qualities as the pickup doesnt pick certain parts of it up. How much of this is true, how much is voodoo is up to you, but they do certainly sound different....

hi Sambo,

i can see you and i have been reading some of the same stuff about pickup placement, and it has colored your perception of why you are hearing differences.

whaddaya say you and i take a look at a few things and see if we can distill a little truth out of this issue.

IMHO the spacing of pickups relative to each other tends to a be more important factor, than issues like the "harmonic node" at the 24th fret.

certainly the proximity of the bridge pickup to the bridge is a huge decision. if its too close, things get very "brittle".

but when it comes to the position of the neck pickup, when used alone, i think you can debunk the importance of the harmonic node, very easily.

lets look at the "theory". if we put the neck pickup exactly where the 24th fret would be, it is indeed at 1/4th the length of the string. this seems like it might be somewhat important.

but, this all goes out the window, the moment you put your finger on the fretboard.

let's imaging you are at the second fret. now the string length is shorter. the 1/4 length point is now where the 26th fret would be. .........hmmmm?

and of course the process continues as you move along the fretboard, in the direction of the bridge. you can now see how important the real estate where the 24th fret would be, probably isn't................unless of course we only play open strings.

now comes the hands on testing, if you are willing to participate:

if you want to take this to extremes, next time you have a standard strat (3 SC pickups) in your hands, play some notes, open or near the head end of the fret board.

then switch between Bridge, Middle, and Neck singles. (forget the 2 and 4 positions for now, that's a whole 'nuther story.)

make a mental note of the different chartacter of the 3 pickups.

now move to the 21st (or 22nd if ya have one) fret. play some notes, and again switch between the 3 pickups.

which 2 pickups sound almost exactly alike?

the answer will surprise you until you examine things closely. then it will make perfect sense.

you will begin to look at pickup placement, from an entirely different perspective, than you had before.

tell me what you think, after you've tried this.

thanks,

unk

[Maiden69]

The reason why the difference in the tone you hear is a matter of physics... the string vibrates i an ondulating pattern... the closer to the ends the smaller the ondulations and the "higher " the frequenzy. The closer to the middle the more round or bassy the note will be! this is why te neck bridge on a 24 fret sound a lot tighter than the 22 fret. Also if you place the bridge pup too close to the bridge the sound can be too thin. I don't think that there can be an exact placement, but I will have it at least 1" or more from the saddles.

[GregP]

The differences in placement for the neck pickup in 24-fret vs. 22-fret aren't related to harmonic node. The myth of the "harmonic node" has been dissected and debunked in numerous threads. Of course, there IS going to be a difference in tone, but it's not related to the harmonic node.

[CrazyManAndy]

This is one of the best places I've found concerning the subject:

http://www.till.com/articles/PickupResponse/index.html

A lot of math, theory, and such so be prepared . As a side note, if I recall correctly, pickup position matters more the closer you get to the bridge. For example, the difference between the neck and middle pickup would be less than the difference between the middle and bridge pickup. Though, I am not an electronics expert.

CMA

Edited February 1, 2007 by CrazyManAndy

[Sambo]

Right. Anyone doing a physics major here?

I think the thing many people forget is that a string isnt just vibrating in one way, its more than one (hence why you get more than one harmonic when you pluck a string). Now, if your pickup is under a harmonic node, where there is NO vibration at that exact point, then your pickup IS NOT going to pick up that harmonic. Hence, you get less harmonics in your sound under a harmonic node. The neck pickup in a 24 fret guitar is probably under a harmonic node, but maybe not one thats audible under normal conditions anyway, so the difference might not be as noticable.

As for the difference being more closer to the bridge ya get, i can see that.

And just for reference, the human ear isnt a useful tool for assessing tonal constituents of a guitar signal. Get a decent oscilloscope.

But to be honest, the actual difference is negligable in any ways. It, as with most things in building and choosing guitars is a matter of taste.

S

PS: OOOOOOOOOH --> http://www.till.com/articles/PickupResponseDemo/index.html

[Robert_the_damned]

Right. Anyone doing a physics major here?

first year phyiscs degree here!

I think the thing many people forget is that a string isnt just vibrating in one way, its more than one (hence why you get more than one harmonic when you pluck a string). Now, if your pickup is under a harmonic node, where there is NO vibration at that exact point, then your pickup IS NOT going to pick up that harmonic. Hence, you get less harmonics in your sound under a harmonic node. The neck pickup in a 24 fret guitar is probably under a harmonic node, but maybe not one thats audible under normal conditions anyway, so the difference might not be as noticable.

This is correct. A pickup in the exact 24th fret possition will pickup virtually no even but lots of odd harmonics (ie no 2nd but lots of 1st and 3rd). HOWEVER, guitar pickups sample the string over a very long length (I'd estimate a humbucker is 'listening' to at least two and a half inches in length of the string, obviously getting weaker signal further you go from the pickup), and so you wont get a case of a pickup not getting any of a particular harmonic unless its got virtually no thickness (a single coil isn't even close to this 'point' pickup)

And just for reference, the human ear isnt a useful tool for assessing tonal constituents of a guitar signal. Get a decent oscilloscope.

Oscilloscopes are good but wouldn't be that helpful in this case as its very hard to judge wave forms like guitar signals (they're very complex). A spectrum analyser is what you want but they're about the cost of two new gibsons plus a bit.

But to be honest, the actual difference is negligable in any ways. It, as with most things in building and choosing guitars is a matter of taste.

most sensible comment yet.

http://www.till.com/articles/PickupResponseDemo/index.html

That's essentially a virtual spectrum analyser with a gutiar pluged in. As I'm sure you can all see there isn't a huge differance between the two pickup possitions but there is a big differance between a bridge and neck pickup. (This program is good but not acurate, for instance the freqency responce 1 inch from the nut should be exactly the same as 1 inch from the bridge but it isn't on that program)

Robert

[Mickguard]

Related question: what about the effect on sustain? I've been playing more and more on the neck pickup lately, in part because the brige pickup's combination of needle-sharp tone and shorter sustain.

In the meantime, I've got a single-pickup guitar in the works---and I've been thinking that maybe I'll be better off placing the pickup closer to the neck, if not in the traditional neck pickup.

Any thoughts on the pros and cons?

[jnewman]

I think the thing many people forget is that a string isnt just vibrating in one way, its more than one (hence why you get more than one harmonic when you pluck a string). Now, if your pickup is under a harmonic node, where there is NO vibration at that exact point, then your pickup IS NOT going to pick up that harmonic. Hence, you get less harmonics in your sound under a harmonic node. The neck pickup in a 24 fret guitar is probably under a harmonic node, but maybe not one thats audible under normal conditions anyway, so the difference might not be as noticable.

This is correct. A pickup in the exact 24th fret possition will pickup virtually no even but lots of odd harmonics (ie no 2nd but lots of 1st and 3rd). HOWEVER, guitar pickups sample the string over a very long length (I'd estimate a humbucker is 'listening' to at least two and a half inches in length of the string, obviously getting weaker signal further you go from the pickup), and so you wont get a case of a pickup not getting any of a particular harmonic unless its got virtually no thickness (a single coil isn't even close to this 'point' pickup)

The statement about a 24th fret pickup not picking up even order harmonics is at best misleading. First of all, the second harmonic actually only has one node, which on an unfretted string is over the 12th fret, and an antinode, or area of maximum amplitude, over the 24th fret. It is not until the 4th harmonic that you get a node over the 24th fret. It is not until the 8th harmonic that you have another harmonic with a node directly over the 24th fret. Then the 12th, then the 16th, etc. This is true but mitigated by the width of the pickup, as you say, if you are playing nothing but open notes. The moment you fret a string, the "24th fret node" has moved towards the bridge and is no longer over the pickup.

The nth order harmonic divides the string length L into sections of length L/n with nodes between the sections. If you want to have a node at L/4, i.e. the 24th fret on an open string, then you have to have sections divisible into L/4. So you get (L/n)/(L/4)=4/n. For there to be a node at L/4, 4/n has to be a whole number, so n has to be a multiple of 4.

If you put a pickup directly under the 12th fret, or half the string length, then for an unfretted note, you would get only odd-order harmonics as any even order harmonic has sections divisible into L/2.

But again, the moment you fret a note, this all goes out the window!

Edited February 1, 2007 by jnewman

[unklmickey]

...I've got a single-pickup guitar in the works---and I've been thinking that maybe I'll be better off placing the pickup closer to the neck, if not in the traditional neck pickup.

Any thoughts on the pros and cons?

well a well respected colleague of mine would say for a HB, put it at the bridge. for a SC put it at the neck.

i don't necessarily disagree with that.

but if i were one who plays much of the time at the end of the fretboard (20th fret), i would NEVER put a SC at the neck.

if you read my previous post after

now comes the hands on testing, if you are willing to participate:

and try that little test, you'll understand why.

(i won't tell you why, it's better if you experience it on your own.)

on a related thought, just like goldilocks, i find the middle "just right".

unfortunately, the place where the middle pickup resides on a strat, is exactly where i pick, so the pickup kinda gets in the way.

so, i think the tonal issues, what kind of pickup, where you play on the fretboard, and where you pick, all need to be considered determining placement in a single pickup build.

i know that doesn't look like it helps much. but, it's the best i can do.

unk

[Primal]

Related question: what about the effect on sustain? I've been playing more and more on the neck pickup lately, in part because the brige pickup's combination of needle-sharp tone and shorter sustain.

As mentioned by Maiden69, as you move closer to the bridge, the amplitude of the vibrating string decreases. When using the bridge pickup, as the note decays, the pickup has less and less vibrating string to detect.

As an example, and one that is only for the sake of demonstration (these values are all fabricated, but still convey the general idea):

At the 12th fret:

Distance traveled by the vibrating string right after being picked = 4mm

Distance traveled by the vibrating string after 5 seconds = 2mm

Difference between the two = 2mm

At the bridge pickup:

Distance traveled by the vibrating string right after being picked = 1mm

Distance traveled by the vibrating string after 5 seconds = 0.25mm

Difference between the two = 0.75

If we do a few calculations, we can determine that after 5 seconds, the vibrating string loses 50% of its energy while the string at the bridge pickup loses 75% of its energy (I'm not sure if this statement is correct since I doubt the relation between the distance the string vibrates and the energy of the vibrating string is linear). Still, you can see how they relate.

That was far more long-winded than I had anticipated.