Stereo to Μono mixer for guitars with stereo pickups

Stereo to Μono μixer for guitars with stereo pickups
Custom made mixer for use with a 1978-Gibson ES-355 guitar or any other guitar that has stereo output pickups with common ground.
With this mixer the stereo output of a guitar (the two pickups) is summed into a single mono output. You can use a Y stereo to mono cable to connect your guitar to the mixer.
Channel-1 has a phase reverse switch just in case you need to adjust and match the phase e.g. if your pickups have 180° difference in phase.
It actually is a 3-to-1 mono mixer that features separate volume controls for each channel and a phase reverse switch for channel-1. The volume controls offer +6dB amplification in the max position (0dB is at 12 o'clock position). If you use the first two inputs for your stereo guitar you can also use the third input to connect a second guitar with mono output or you can also leave it unconnected.

The dpFX 3 channel mixer (3-to-1 mixer) is a mono mixer suitable for pedals & instruments; guitar, bass or any other instrument with similar pickups.
It can be used as a summing box that can take up to 3 mono-signals and combine them into a single mono-output. It can also be used to combine the two channels of a stereo signal into a single mono-output. It makes use of low distortion, low noise op amps & features high-impedance JFET inputs that can be driven by instruments (guitar, bass etc) or line level signals as well.  Each input has a volume knob ranging from mute, up to +6dB gain.
It works with standard pedal power supplies and has a very low current consumption. The mixer is always on when power is connected (external LED is lit when ON)

▹ Input impedance: 5MΩ
▹ Output impedance: 100Ω
▹ Voltage required: 9Volts DC (max 12V)
▹ Polarity: Center Negative
▹ Current consumption: 15mA (@ 9V)