4-Input High-Z Mixer PUBLIC

4-Input 1-Output High-Impedance Mixer for Guitar.

4-input 1-output high-impedance mixer for guitar. Controls Include: Levels 1 through 4, Output Gain, and Volume. Inputs will accept signals from passive or active guitars, effects, effects chains, guitar preamps, or guitar processors. Recommended for 6/7-string guitar (not suitable for 8-string guitar or bass-guitars). General frequency range per input: 62 Hz to 10 kHz. Maximum gain = +2.8 dBV @ 630 Hz per input with all controls at 50% and using a 1V 1kHz input signal. Maximum gain = +21.5 dBV @ 1 kHz per input with all controls at 100%. Note: Circuit gain is proportional to the number of inputs used. Maximum gain = +14.8 dBV @ 1 kHz with all inputs given a 1V 1kHz signal and all controls at 50%, or +33.5 dBV with all controls at 100%. Do not use with all controls at 100% except as a worst-case test while breadboarding. The circuit can be the basis of a stomp-box or rack-mount project. The batteries can be replaced by a regulated dual-polarity +-9V DC power-supply providing >= 30 mA of current. Output phase is inverted compared to input phase. To make in-phase, install an extra capacitor in the signal path at the output.