Up to this point in the series we’ve focused on characterising each sound with a single frequency representing its pitch. In today’s article we’ll consider the other frequencies present in musical sounds.

Compound frequencies, harmonics, blah blah blah!

Right?

No; actually in the real world, most sounds are made up of more than one frequency. We’ll forgo the actual full-on physics formula for sound creation, as that is way past our scope here…BUT…what IS of importance is that most sounds have a blend, or ratio, of multiple frequencies that resonate to create the sound that you hear. Hence the term ‘compound’ frequencies.

Harmonics

Now, speaking of this resonance business; all of the frequencies contained in a sound except for the main (‘fundamental’ or ‘dominant’) frequency are called harmonics. Usually, they are found at precise multiples of the main frequency. The pattern is this: Click to read the rest…

Today we’re taking a quick breather in the Frequency Fundamentals series, for an introduction to two important topics for audio engineers: EQ Feathering and Spectrum Analyzers. Once you’re familiar with both of these, you’ll be ready for the final part in the series, on harmonics of sounds.

…Here is the answer to the mystery bonus question at the end of the last article. If you’ll remember, I asked:

What is EQ feathering?

Answer: EQ feathering is a way of applying, or rather spreading equalization through adjacent and tangential frequencies on both sides of the main frequency that you are trying to adjust, thus resulting in a smoother tone curve.

Confusing?

Don’t go away just yet. Let’s look at a working example….it will be a much clearer answer! Click to read the rest…

We now continue our discussion of the 10 audible octaves. We left off at Octave 5 in Part 1. Onward….

Characteristic Sounds: Bands 6-10

Octave 6 (640-1280Hz)

This is midrange land again. Remember Octave 5, and now 6 are referred to as the projection octaves.

Specifically, here in Octave 6 rests the difference between Click to read the rest…