Proposed color code for Plaiades microphone equalizers

Pleiades proximity compensating microphone passive equalizers for flat frequency responce from 20Hz to 20KHz at any distance from 4 ft to 0in

                       Red     Orange.   Yellow   Yel/green    Green   Blue    Violet   

Distance of     4ft         2ft          1ft            6in         3in      1/2in      0in

mc for flat 

20Hz-20KHz 

Pleiades 

turnover       25Hz    50Hz     100Hz     200Hz      400Hz       800Hz   1.6KHz

Frequency 

Parallel

Inductor     1.28H   640mH.   320mH     160mH    80mH       40mH     20mH

Inductance

Each EQ is a variable low or high shelving filter by decreasing or increasing the optimum mic to source distance respectively.

Each EQ is implemented inside a Neutrik module female to male XLR 3 part adapter for ease of balanced connection to microphone.

The module in the middle of the Neutrik XLR adapter houses the inductor and is painted externally in the color code as above. The code representing the visual electromagnetic frequency spectrum makes easy the quick  choice of a Pleiadws filter without reading numbers.

The coil inductor is connected in parallel to the microphone signal ie in pins 2 and 3 of the Neutrik XLR adapter (live, return). It may be a made by winding an insulated thin wire several turns on a toroidal core, Magnetec Nanocrystalinne or ferrite etc.

Pleiades filters can be connected in cascade and nature gave the useful property of being able to add turnover frequencies.

For example:

If the use of an AKG D112 is required to record vocals or any source from approximately 20Hz to 20KHz, (this depends on mic and source of course) at less than 3in a green and yellow Pleiades EQ can be connected in cascade giving a compensation turnover of 400Hz + 100Hz = 500Hz