Double Bass Locating harmonics

[Les Fret]

I don't understand that explanation. Where are the 4th and minor 3rd?

going down (towards headstock) on the string from the 12th 'fret' you have: (notes between brackets indicate the 'fret')
root (12) 3rd (9), 5th (7), octave (5), 3rd (4) 5th (+3), 7th (-3)

going up (towards the bridge ) it are the same intervals.
So on each string the natural harmonics form a 7 chord.

 

[tstone]

>> I don't understand that explanation. Where are the 4th and minor 3rd?​

Since Mr. Tom Gale does not appear to be around at the moment, I will attempt an answer.

Say we're talking about the G string. Touch it lightly at its midpoint and you get the second partial, a G an octave above the open string.

Now move your finger up the fingerboard (towards the bridge) the distance of a perfect fifth (i.e., 7 "frets") from the first touching point, or node, and you will find the third partial, a D.

Move it up a perfect fourth (5 "frets") from that second node and you will get the fourth partial, another G.

Move it up a major third from there and get partial number five, a B. Move an additional minor third and get a D.

That succession of 8ve, 5th, 4th, M3rd, m3rd comprises the intervals Tom Gale was referring to.

If you start at the middle of the string and move your finger towards the nut instead of towards the bridge, the physical distances between the nodes will be the same, but the succession of intervals will not follow the neat progression of 8ve, 5th, 4th, M3rd, m3rd.

By the way, that neat integer progression breaks down after the 6th partial. The seventh partial is non-diatonic, lying between a major sixth and a minor seventh, so the interval you have to move your finger is somewhere between a major second and a minor third. But on most basses, you will have run out of fingerboard by that point anyway ;-)

 

[robobass]

I think of it from the physicists point of view, i.e. nodes lie at successive divisions of the string. touch exactly in the middle and you produce an octave. Touch a third of the way from either end and you get a twelfth. A quarter of the way = second octave, etc. Down at the nut end, the higher nodes don't correspond to actual note positions on the fingerboard.

 

[Les Fret]

>> I don't understand that explanation. Where are the 4th and minor 3rd?​

Since Mr. Tom Gale does not appear to be around at the moment, I will attempt an answer.

Say we're talking about the G string. Touch it lightly at its midpoint and you get the second partial, a G an octave above the open string.

Now move your finger up the fingerboard (towards the bridge) the distance of a perfect fifth (i.e., 7 "frets") from the first touching point, or node, and you will find the third partial, a D.

Move it up a perfect fourth (5 "frets") from that second node and you will get the fourth partial, another G.

Move it up a major third from there and get partial number five, a B. Move an additional minor third and get a D.

That succession of 8ve, 5th, 4th, M3rd, m3rd comprises the intervals Tom Gale was referring to.

If you start at the middle of the string and move your finger towards the nut instead of towards the bridge, the physical distances between the nodes will be the same, but the succession of intervals will not follow the neat progression of 8ve, 5th, 4th, M3rd, m3rd.

By the way, that neat integer progression breaks down after the 6th partial. The seventh partial is non-diatonic, lying between a major sixth and a minor seventh, so the interval you have to move your finger is somewhere between a major second and a minor third. But on most basses, you will have run out of fingerboard by that point anyway ;-)

I think we mean exactly the same. But I refer to the intervals in relation to the tonic, so you have the 7 chord. Tom was referring to the intervals from one note to the next when going up

 

[Tom Gale]

>> I don't understand that explanation. Where are the 4th and minor 3rd?​

Since Mr. Tom Gale does not appear to be around at the moment, I will attempt an answer.

Say we're talking about the G string. Touch it lightly at its midpoint and you get the second partial, a G an octave above the open string.

Now move your finger up the fingerboard (towards the bridge) the distance of a perfect fifth (i.e., 7 "frets") from the first touching point, or node, and you will find the third partial, a D.

Move it up a perfect fourth (5 "frets") from that second node and you will get the fourth partial, another G.

Move it up a major third from there and get partial number five, a B. Move an additional minor third and get a D.

That succession of 8ve, 5th, 4th, M3rd, m3rd comprises the intervals Tom Gale was referring to.

If you start at the middle of the string and move your finger towards the nut instead of towards the bridge, the physical distances between the nodes will be the same, but the succession of intervals will not follow the neat progression of 8ve, 5th, 4th, M3rd, m3rd.

By the way, that neat integer progression breaks down after the 6th partial. The seventh partial is non-diatonic, lying between a major sixth and a minor seventh, so the interval you have to move your finger is somewhere between a major second and a minor third. But on most basses, you will have run out of fingerboard by that point anyway ;-)

Very well said.
Tom Gale

 

[damonsmith]

I think there is some confusion here about the difference between the 4th partial and the 4th scale degree. The 4th partial means the 4th division in the string, which is the location of a harmonic.
The 4th (for example C on the G string) scale degree does not appear in the overtone series, theoretically it does appear in the subtones.

The order the scale degrees appear in in the overtone series in terms of partials is 1, 1, 5, 1, 3, 5, b7 and so on.

Because harmonics are infinite every traditional stopped pitch on the bass has a coresponding harmonic when the pitch is played in tune and you lift your finger to touch the string.
I don't have all day to give you all 12 (not mention the harmonics mirror at the octave), but in half pos. on the G string you get: an Ab over Ab an A over A and D over Bb. That means an Eb can be found over the first Eb on the D string, but it is VERY unstable, not to mention the harmonics start deviating from western tunning after the major third.

You can figure this out with a tuner pretty easily. The upper partials can end up being useful but can take time to really get to speak, they each need a little different bow pressure, speed and placement to speak clearly.