This midrange filter for sound systems was found in the May 1988 issue of Radio Electronics magazine. The circuit is based on a dual amplifier that must be powered by a symmetrical source.
The LDO series (Low Dropout) TPS80 from Texas Instruments (www.ti.com) can provide output voltages...
The presented circuit uses an operational one of the time. The circuit is from an 80's manual and...
The operation of this circuit is old, but the configuration can be elaborated based on modern...