I’ve got a pair of 3A Sigs. I’ve found that most bass problems stem from speaker / listening position placement rather than component issues.
I used the ’odd dimensions’ method from the manual. Have you tried moving them around using this procedure? I also find that my speakers sound best without any toe-in. Try changing that aspect as well. Also try to measure how high your ears are from the ground. This would affect the cabinet tilt-back angle (and as a result frequency response).
You could also be sitting in a null in the mid bass frequencies. Experiment with moving your seat back and forth a few inches. You might find it makes all the difference.
Finally, you can adjust the contour controls. Try reducing the level of the midrange by 1-2 dB. This might give you the mid bass balance you seek.
Hope this helps!
I used the ’odd dimensions’ method from the manual. Have you tried moving them around using this procedure? I also find that my speakers sound best without any toe-in. Try changing that aspect as well. Also try to measure how high your ears are from the ground. This would affect the cabinet tilt-back angle (and as a result frequency response).
You could also be sitting in a null in the mid bass frequencies. Experiment with moving your seat back and forth a few inches. You might find it makes all the difference.
Finally, you can adjust the contour controls. Try reducing the level of the midrange by 1-2 dB. This might give you the mid bass balance you seek.
Hope this helps!