Booster with 5-Band Tone PUBLIC

Special 5-band tone-control circuit using dual op-amp IC.

Special 5-band tone-control circuit using dual op-amp IC. Controls Include: Input Gain, Drive, three Mid controls, Bass and Treble controls, and output Volume control. "Special" means the circuit in especially designed for electric guitars where the Mid controls do not affect signal levels, like Bass and Treble, but shift the centers of specified frequency bands. Input stage is built around a TL082CP dual JFET-input op-amp IC with two low-end cutoffs (80 Hz and 40 Hz) and one high-end cutoff (18 kHz), which reflect frequencies optimized for 6-string guitar in standard tuning. Suitable for stomp-box or rack-mount applications. For overdriving to get distortion with large input signal, replace the specified IC with an NJM5532M, but which will drain the batteries more quickly. In that case, the batteries should be replaced by a regulated dual-polarity +-9V DC power-supply providing at least 40 mA of available current. Total gains per frequency with all pots at middle positions, and using a 1 V p-p 1 kHz input signal, are; -4.6dBV @ 16Hz, 0dBV @ 20Hz, +3dBV @ 25Hz, +10dBV @ 40Hz, +20dBV @ 100Hz, +23dBV @ 250Hz, +22dBV from 630Hz to 1.5kHz, +21dBV @ 4kHz, +17dBV @ 10kHz, +15dBV @ 15kHz, and +13dBV @ 20kHz. Absolute maximum total preamp gain = +46dBV @ 250Hz.