http://electroharmonix.ronsound.com/art ... ttack.html
I could read:
Someone has more info about this unit or even a schematic ?The KO Attack EQ operates on a single 9 volt battery which supplies power to the LM324 quad op-amp that is the sole chip in the effect.
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In reality, the Attack Equalizer is a glorified 3-band rotary EQ. The controls are labeled as (l-r): Fundamental, Blend, and Attack but the schematic lists the controls as Bass, Mid, and Treble. After seeing the schematic, former EH engineer Howard Davis remarked:
"If I were to redo it, I'd certainly improve those PRIMITIVE low pass and high pass filters! Also, what is called the "midrange" control is actually a direct signal level control, not a bandpass, as a midrange control should be."
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The main (only) disadvantage to this model is that the circuitry was changed to accomodate 2 4558P dual, internally compensated, high performance op-amps, which required positive and negative power supplies. This resulted in, yes, 2 nine volt batteries for operation which are switched on or off by a rear-mounted power switch.
thanks in advance,
analogguru