Harmonics, Fundamentals, you know, all that good stuff..

[OMNIFEX]

Hey!

 

Was wondering if anyone can tell me in bass

frequencies/notes, what would be considered

the fundamental, and, what would be the

harmonic.

 

 

And while we are talking bass notes, when does

the Fundamental turn into the 1, 2, and/or 3rd

Harmonic

 

Lets use a 1/3 octave to make it easier for me

to understand

 

20, 25, 31.5, 40, 50, 63, 80, 100, 125 Hertz

 

I'm trying to figure out what notes are used

to give that heavy bass sound. How much

the fundamental, and harmonic, settings

play a factor in acompishing that heavy

bass sound.

 

 

Thanks !

[Kennykeys]

While I can't answer specifically,I do know that bass guitar sounds are largely made up of harmonics. That is why we can hear notes whose fundamental frequency is lower than the capability of the driver/enclosure. In other words, you don't need a speaker box that can go down to 30hz in order to accurately reproduce a bass guitar.

[J the D]

A note's sound is made up of the fundamental frequency (the lowest frequency in the harmonic structure and the frequency which gives the note its name such as 55 Hz being an A) and a series of higher frequencies that are called harmonics. Generally harmonics fall a set pattern such that the first harmonic (110 Hz)is an octave above the fundamental (55 Hz), the second harmonic is a fifth above that (or an octave and a fifth above the fundamental), the third harmonic is a third above the second harmonic and since a fifth and a third make up an octave the third harmonic (220 Hz) is an octave above the first harmonic (110 Hz)and two octaves above the fundamental (55 Hz). The intervals start getting more funky above the third harmonic but they gone on above our hearing range.

 

The individual tone a note makes is determined in part by the amplitude of the individual harmonics. The amplitude of the first harmonic is typically almost as large as the fundamental. Since the fundamental of a bass note is in the lowest part of the human hearing range most people hear as much or more first harmonic as they do the fundamental. The neat thing is that the brain will sort of reproduce the lower frequencies that are missing when the sound gets to it.

[Jlliu59]

The formula for harmonics is as follows:

 

(n+1)*Fo.

 

Fo : fundamental

n: number of the fundamental

 

so, is the fundamental is Fo=55Hz then

 

1st= 110Hz; n=1

2nd= 165Hz; n=2

3rd= 220Hz; n=3

4th=275Hz; n=4

and so on.....

 

(The hearing range can go up to 20,000 Hz)

 

That said, the 2nd harmonic is actually an octave above your musical 5th. That's how certain musical intervals are related. Higher frequencies are needed to resolve more distantly related harmonics.

 

However, J and D is correct about the the brain filling in the missing low frequencies. There's a phenomenon called the missing fundamental

 

The tone still changes as those frequencies are taken out, but the pitch is still percieved at the same octave.

 

Let's say you you put a sharp high pass filter on a bass note with a fundamental at 55Hz. it will sound very different and lower than a note being played at 110Hz, because it's harmonics are being played at all those frequencies listed above while the 110Hz is only played at 110, 220, 330, 440.....

 

So, a note played on a B string of a 5 string bass, cannot be replaced by some B played an octave higher and EQed.

 

Some of tone also depends on the amplitude change in time. So compression also can make your bass sound fatter.

[J the D]

 

Originally posted by Jlliu59 That said, the 2nd harmonic is actually an octave above your musical 5th. That's how certain musical intervals are related.

 

 

 

You are right. Sorry for my grammatical error. You are determining the second harmonic by taking the fifth up from the fundamental and adding an octave. I'm adding an octave to the fundamental and taking the fifth up above that. We arrive at the same place.

[el_virto]

If i remember anything from my acoustics and electro acoustics classes...

 

You're right about the missing fundamental side of things...that's how Waves MaxxBass processors work.

Also for a clear example of harmonic content hit low and high notes on a piano..the low notes are rich because a lot of the harmonics are audible; whereas on the highnotes it's more muted because the harmonics are above 20k

 

As for the math side of it..the fundamental IS the first harmonic..and each successive harmonic is a multiple of that. The 2nd harmonic is the octave 2x fundamental. 3rd harmonic is 3x fundamental (an octave and a 5th...good representation of this is a 7th fret harmonic on a guitar...cutting the string in 3..octave and a 5th up)

 

1f = fundamental ie A440

2f = 2nd harmonic A880

3f = 3rd harmonic - approx E1320

4f = 4th harmonic - 2octave - A1760

5f = 5th harmonic 2 octave + M3rd = C# 2200

 

numbers may not be exact to pitches depending on your tuning system..but you get the idea

 

correct me if you think i'm on crack...it's 5am and i haven't done this for a bit..