Why is a note sometimes a 4th and sometimes an 11th?

1. Is an 11th the same as a 4th?
2. Is the 4th the 11th?
3. What makes an 11th chord?
4. Why is it called perfect 4th?

Is an 11th the same as a 4th?

The interval can be also described as a compound fourth, spanning an octave plus a fourth. Since there are only seven degrees in a diatonic scale the eleventh degree is the same as the subdominant. The eleventh is considered highly dissonant with the third.
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Eleventh.

Is the 4th the 11th?

So, a note would be described as a fourth if we were talking about interval distances, and an 11th if it was a chord tone (typically preceded by the root, 3rd, 5th, 7th, and 9th).

What makes an 11th chord?

In music theory, an eleventh chord is a chord that contains the tertian extension of the eleventh. Typically found in jazz, an eleventh chord also usually includes the seventh and ninth, and elements of the basic triad structure. Variants include the dominant eleventh, minor eleventh, and the major eleventh chord.

Why is it called perfect 4th?

The term perfect identifies this interval as belonging to the group of perfect intervals, so called because they are neither major nor minor. Play (help·info)), while in equal temperament a perfect fourth is equal to five semitones, or 500 cents (see additive synthesis).