Nodes?

[unusual71]

Ok so my friend was telling me if you have your neck pickup where the 24th fret would be(after a 22fret board) that you get some kind of node, or something to do with nodes like that. I'm building a guitar and would like to know of any specific pickup placement for like a round, warm tone? or somewhere i definitaly should not place the pickups? thanks in advance

[daveq]

I'd like to hear what others have to say about this but I've always thought of that 24th fret node as being a bit of a myth. I mean - I know it's definitely there but pickups don't lock in on just that one place on the strings.

The other thing is, when you start fretting other notes (other than the open note), the placement of the nodes start moving around.

I guess in general, there probably is a spot where people tend to like the pickup to be placed but I have a feeling that too many people assume it's because of that 24th fret node.

BTW - nodes (as I understand them) are the places on the string where the vibration is minimal.

[KeithHowell]

Yes from my university physics days a node is the point in a waveform where it crosses zero. ie the vibration is zero. The anti-node is the point with the most displacement which is the peak of the waveform in a sin-wave.

Keith

[erikbojerik]

Yep.

The idea behind placing a pickup at the 24th fret position was to pick up harmonics when playing open or on the first few frets. When you pick an open string, you don't get actual nodes at the 12th & 24th frets, but if the sustain is good you can get smaller standing waves on top of the fundamental that correspond to the notes at main harmonics (12th fret, 24th fret, etc).

As you fret in the first few positions, of course the harmonics move but at the 24th fret position they don't move so much. For example, if it 1 inch from the nut to the first fret, the 24th harmonic (1/4th the fundamental) will move by 1/4", still close enough for the pickup to see it (if placed correctly).

As I recall, the strat pickup placements are dictated by that (neck @ 24th fret, middle @ 36th fret, bridge @ 48th fret) but I've never actually measured their positions from the nut to verify this.

[thedoctor]

To put it VERY simply, nodes are the effective PLAYED length ( in other words, fretted length) of a string divided by an integer. An integer is any number without fractions or decimals. Whole numbers. The 12th fret is the open-string length divided by 2. The 24th fret is the open-string length divided by 4. Etc. As you fret a string you change the location of integer nodes and that makes it impossible to place a pickup under a node in all times. A compromise is in order and that is why you find slanted pickups on some guitars. They are trying to cover more nodes and get a more even output and harmonic balance. Hey, I think my old Dodge has a harmonic balancer! I'm gonna try plugging it in to my Strat!!