Dogs can hear at up to 40,000 HZ. We can only hear up to 20,000 HZ. If it was possible for us to hear from 0.1 HZ to 1,000,000,000 HZ then it will be cool to hear high sounds and low sounds. But unfortunately we cannot hear that High or Low.

There are dog whistles you can buy that emit a high frequency. Dogs can hear the whistle, we cannot hear it because dogs can hear higher than us.

Every octave adds something to the music. The high notes add brilliance. The low notes add depth and make it sound like its played in a theater. I wonder what the music will sound like if add frequencies beyond our hearing For example if we could add 8 HZ to the music what kind of depth will It give? Or if we could add 200,000 HZ to the music what kind of brilliance will It give?

Even if we could hear a huge frequency range lets say from 0.001 HZ to 1,000,000,000,000 HZ. Frequencies as low as 0.1 hertz will be hard to produce, it speaker will have to be big, move a lot of air, and use up a lot of power. Frequencies as high as 1,000,000,000 HZ will be hard the produce too because it will required a fast CPU to produce and a high sample rate.

The higher the sample rate and more notes that are playing. The longer it takes the computer to write the wave. We could try writing out to disk first then playing back. But that will take up a lot of space. The computer has to do more work to make higher frequency sounds. The speaker has to do more work to make lower frequency sounds. Another thing with very low frequencies is that the notes have to be long.

In music notes can be harmonious (meaning that they do go together or they sound nice together) or discordant (meaning that they don’t go together or they sound bad together). Simple ratios like 3/2,5/4,5/3,4/3 are harmonious. More complex ratios like 7/5,7/4,16/15,7/13 are discordant.

The interval between C and C# is called the minor second and is discordant.
The interval between C and D is called the major second and is neither discordant nor harmonious.
The interval between C and D# is called the minor third and is harmonious.
The interval between C and E is called the major third and is harmonious.
The interval between C and F is called the fourth and is harmonious.
The interval between C and F# is called the diminished fifth and is discordant.
The interval between C and G is called the fifth and is harmonious.

Chords are made out of 3 notes.
A major chord is made of base note, a note 4 semitones up and a note 7 semitones up.
A minor chord is made of base note, a note 3 semitones up and a note 7 semitones up.

You can change a chord from a minor chord to a major chord or from a major chord to minor chord. By just moving one of the notes up or down a semitone.

For example a major chord is C E G. a minor chord is D F A.

If you move all three notes of a major chord up or down one semitone. Then it still remains a major chord, the same thing with the minor chord. You can repeat this many times as you like and it will still remain a major chord or a minor chord. In fact you can play the chord in different keys and It will still be a major chord or a minor chord.

The same thing happens the melody you move all the notes up or a certain frequency and it will still sound same except for its pitch. In fact you play the same melody in different keys and it will be still be recognizable.

There are whales songs that whales use to communicate with each other. They could have notes from 16 Hz to 128 Hz they can sort of complex in a way. They might have a melody. The whale songs do have a pattern.

Philip Clapham, an Marine biologist saids that the songs of the whales are probably the most complex songs in the animal kingdom.