I stumbled across an interesting post on musiclibraryreport.com.
It links to a really cool interactive frequency range chart. It shows major musical instruments and their frequency spread related to an 88-key piano.
While the chart focuses on musical instruments, I found useful for sound effects mastering as well.
Field recordists with a music background will find the info familiar. What’s different is the way the chart is presented, for two reasons.
I like how it expresses the information in the Spectrum Data box. Hover your mouse pointer on the spectrum. The box shows how altering frequencies will affect listeners.
For example, adding excessive frequencies in the high midrange “can bring on listener fatigue.” Frequencies above 16 kHz are “sensed more than heard.”
It’s interesting to think about how sound can affect the listener in an abstract sense irresepective of what the sound actually is.
Perhaps the area below the image of the keyboard is more useful to sound editors. Frequency ranges are defined by keywords. Want to add more ‘edge?’ Play around with the frequencies between 3900 and 5500 Hz.
I like this since I usually tweak my recordings based on feel and feedback more than surgically notching textbook frequencies. Changing the feel of a sound based on abstract effects like ‘mud’ or ‘punch’ is a compelling way to approach mastering a sound effect.
Basically it is a great cheat sheet that has some abstract ways of looking at technical data.
Would it work for sound effects?
It made me wonder if it would be possible to create a similar chart for sound effects.
Field recordings are generally more complex. They can comprise many different voices. They alter over time. Some sounds are broadband, or work in harmonics so the chart would be more complex.
My first thought is that a list of common frequencies to remove or notch would be helpful. Some ideas:
- fluorescent light buzz
- monitor whine
- air conditioning hum or HVAC
- compressors, fridges
- truck backing beeps (when they interfere)
- line buzz
Of course not every monitor whine, for example, will occur at the same frequency. However common sounds would have similar frequencies or harmonics so a range of frequencies may work.
Or perhaps frequencies to enhance or diminish aspects of ambiences:
- thicken crowd
- lighten background city rumble
- enhance birdsong
- lessen wind buffets
- give definition to ‘white noise-like’ sounds: waterfalls, rain, ocean, wind
How about sound design? Some frequencies to accomplish an emotional response:
- increase oppressiveness
- add grit/lo-fi
- brighten, lighten or add sparkle
- annoy or needle
And maybe equalization tricks or filters:
- fake an off-stage effect: put vocals behind a door or a wall, or filter birds for an interior perspective
- fake distance – make a closely recorded sound clip seem far away
- add radio or a phone effect to vocals
It would be interesting to see which frequencies are commonly affected though. Food for thought.
What would you like to see in a sound effects frequency chart? Do you have any go-to equalization tricks?