iTunes Equalizer, also called EQ or 10-band graphic equalizer, a handy built in equalizer to let you decide which band you choose to increase, or decrease in frequency (HZ, hertz).
How to Use Equalizer in iTunes
iTunes Equalizer has included 20+ presets for you to easily change the original sound of your music, including Electronic, Jazz, R&B, Rock, etc. For example, If you choose "Electronic", the bands of low ends and high ends have been boost up. This will cause a noticeable effect on your sounds like an electronic style. You could also make your own presets by click the top drop down list. Get it by Windows > Equalizer or simply Option+Command+2
Understand Each Equalizer Slider
If you want to make a custom Equalizer settings, you need to understand what each iTunes Equalizer slide means.
32 Hz: This is the lowest frequency selection on the iTunes Equalizer. This represents the lowest of bass or kick drums frequencies.
64 Hz: This second bass frequency starts to become audible on decent speakers. Again, mostly bass and drum instruments will reside in this region.
125 Hz: Many small speakers, such as in your laptop, can just about handle this frequency for bass information. Therefore, if you turn it up, you'll hear more bottom in your mix.
250 Hz: Guitars and pianos will have a large amount of low end in this frequency range.
500 Hz: Some of the low end of vocals and the mids of bass instruments sit here in a mix.
1K: Most instruments such as guitars, pianos, and snare drums reside in this region.
2K: This frequency is similar to your voice makes when you hold your nose and talk.
4K: 4k is the main frequency that a large portion of many instruments and many electric guitars sit in.
8K: The majority of cymbals and hi-hats are subjected to this region. The upper range of synths, pianos, guitars and many vocals have a lot of information in this range.
16K: The humans can hear just above 20K, hence, this is true high end. If you boost this up, your mixes will sound "sizzly".
Perfect Equalizer Settings?
Someone has generated a perfect equalizer setting? Are you searching for it? I don't think there is a perfect iTunes Equalizer setting, but you can have a try. Here are the suggested settings.
+3, +6, +9, +7, +6, +5, +7, +9, +11, +8 (each slider from left to right)
iTunes Equalizer Tip:
1. Use Command + Option + 2 or Ctrl + Shift + 2 to open iTunes Equalizer quickly.
2. The use of any iTunes equalizer setting other than "flat" means that special effects have applied to the sound. You're no longer listening to the music as recorded on the master.
3. There is NO 'perfect' iTunes equalizer thing. The equalizer settings that generate good sound may probably be unacceptable to another person. Only one thing to confirm: By applying iTunes equalizer, the sound is less "true" than the original one.