Is there supposed to be a volume difference between the single coil and humbucking portions of the EMG-89?
There is a noticeable difference in gain between the single-coil and humbucking portions of the EMG-89. It’s design reflects the fact that single-coils generally have less gain. Obviously, there are tone differences as well, but the gain difference is also a factor. You can compensate for the gain difference by putting an EMG-PA2 (pre-amp booster> on the single-coil portion of the EMG-89. However as the gain of the single coil is increased, there will be less difference in sound between the single-coil and humbucking portions of the EMG-89.