Variable Mid frequency correction box or Pleiades vocal microph9one correction box

At your risk. A variable passive filter to correct for bass, mid heaviness due to proximity effect, Fletcher Munson equal loudness curvs, voice effort curves, low frequency small room standing waves etc. It is the usual Pleiades filter but the inductor is a multitap inductor, currently 12 position. Then in series is a 1K military quality potentiometer. Then in series there is provision for 3 swichable capacitors, say 10nF, 100nF, 1uF. capacitors are for creating a Shure SM7 type notch or band reject filter for removing a high frequency peak, or even for attenuating the fundamental of a singing voice. So all L,R,C are in series and the total connected across the microphone output. The toroidal core used is the Magnetec nanocrystaline M-059-03F6. Starting with 2 turns then multiplying by 1.42 to find yhe next number of turns for next tap. 1.42 times 1.42 makes roughly 2 so frequency cutoff is advancing in octaves. So 2 turns 0.6mH, 3 turns 1mH, 6 turns 2.4mH, 8 turns 4.3mH, 11 turns 8mH, 16 turns 17mH, 23 turns 35mH, 33 turns 73mH, 46 turns 141mH, 66 turns 290mH, 94v turns 600mH. Everything with be attempted to be fitted inside an orange color Hammond guitar pedal size aluminum box. Ie the 2 Neutrik male and female XLRs, the inductor under a 12 position 1 pole rotary switch, the 1K potemtiometer, the 4 position 1 pole switch and the 3 or 4 capacitors. Gray-silver colored knobs. Maybe a provision for disconecting the filter by a switch or an unconnected inductor rotary switch terminal for EQ in or out. Further reading for the bass, mid heaviness effects in the listener's brain mentioned in sentence 2: A Brief History of Early Motion Sound Recording and Reproducing Practices - John K. Hilliard - Journal of the Audio Engineering Society, Volume 3, Number 4, 1985 April