Hi @TauriskYou mentioned frequencies and as you know sounds are...

Hi @Taurisk

You mentioned frequencies and as you know sounds are built on frequencies. In church music there was the 'devils' interval named as such due to it's dissonance but it also involved two notes played thus two frequencies and was avoided by composers and tutors alike for a long time - today it is simply known as tritone and has been in use for a while now - as far as I know, particularly in jazz where tritone substitutions are common.

Whilst each note emits a certain frequency, it's hard to imagine just listening to one note - though there is a composition titled 'One note samba' where the melody note essentially stays the same but not the harmony - a lovely composition.

The following gives a little more insight to certain frequencies and their usage - perhaps worth viewing or rather, listening:


Then according to the following the standard pitch reference used for tuning is concert A and is set at 440 Hertz but there are other Hertz values also assigned:

https://music.stackexchange.com/questions/18969/why-is-a4-the-standard-pitch-reference-for-tuning

Seems a rather complex issue but fascinating.