Characteristics of Musical Sounds

Musical sounds have some characteristics that differentiates them from all other types of sound and they include:

1.  Pitch 
2.  Quality or Timbre
3.  Intensity or loudness

What is Pitch

Pitch can be defined as the highness(height) or lowness(depth) of a musical sound, note, voice or musical instrument. Pitch refers to how light or how deep a sound, or
note can be. A note or sound that is light is said to possess a high pitch while one that is deep is said to have a low pitch.

For human beings’ adult males are said to have a low pitch as their voices are usually deeper than that of female counter-part while women & children usually possess a high pitch as their voices are usually lighter than their male counter-part.

On a piano keyboard the pitch increases as you press the keys from the left towards the right, in other words the sound produced by the keys to the left are deep while those to the right are light. 

The pitch of a bass drum & bass guitar is very low while the pitch of a lead guitar & saxophone is high.
The pitch of the roar of a lion is lower than the pitch of the meow of a cat.

Pitch is related to the frequency of vibration of the sound. The higher the frequency of a sound the higher will be the pitch of the sound & vice-versa.

In four part harmony arranging the four voice parts in increasing order of pitch we have bass, tenor, alto & soprano(treble). The bass voice has the lowest pitch while the soprano has the highest pitch. 

What is Quality or Timbre

Quality or timbre can be defined as the harshness or smoothness of a musical instrument, voice, note or sound. Quality is the characteristics of a musical sound that actually differentiates a note of the same pitch played on different musical instruments. 
Quality or Timbre can be defined as tone colour. Every instruments possesses a unique(tone) colour or sound.
If I play note C of identical pitches on the piano, lead guitar, saxophone, & bass guitar what is actually going to make you recognize the. sound is coming from a particular instrument is their quality. 
The quality of a sound makes it possible for you to differentiate between car horn & gun shot.

Intensity or Loudness

Intensity can be defined as the degree of loudness of a musical sound. Loudness is related to the distance of production. There are various Italian terms that are used to indicate & express the degree of loudness in a musical performance whether vocal or instrumental or both.

Some Italian terms & their meanings

Italian Term	Symbol	Meaning
Piano	p	Soft
Mezzo Piano	mp	Moderately soft
Pianissimo	pp	Very soft
Forte	ff	Loud
Mezzo Forte	mf	Moderately loud
Fortessimo	ff	Very loud
Cresendo	< or cres.	Gradually becoming louder
Decresendo	> or decres.	Gradually becoming softer