====== 5 Band constant Q mini equalizer ======

~~META:description abstract=A 5 Band constant Q equalizer, based on MFBFs.~~
{{tag>audio effects}}

A 5 Band constant Q equalizer, based on MFBFs.

===== Features =====

  * Use 220k alps sliders (15mm travel, led in cursor)
  * PCB must fit in 35x90mm space
  * 12dB boost/cut
  * powered from 2x15V psu

===== Design =====

==== MFBF formulaes ====

{{schematic>mfbf.svg}}

<m>R_{1}=Q/{2 G pi f C}</m>

<m>R_{2}=Q/{2 (2Q^2-G) pi f C}</m>

<m>R_{3}=Q/{pi f C}</m>

Gain : <m>G=1/{2{R_{1}/R_{3}}}</m>

Center frequency : <m>f={1/{2 pi C}}sqrt({R_{1} + R_{2}}/{R_{1} * R_{2} * R_{3}})</m>
===== Electronics =====

  * [[http://sound.westhost.com/project75.htm]]
  * [[http://sound.westhost.com/project63.htm]]

{{:projects:5_band_constant_q_mini_equalizer:5band_constantq_eq.xls|MFBF calculations}}

{{schematic>schematic.svg}}