I agree it may be a phase issue. Maybe the original owner messed with the drivers and mis-wired the woofer on one speaker...if changing wires at the speaker terminals doesn't net a root cause. You could ask the person you purchased them from if he did any experimentation or repairs.
Also, you could purchase a RS SPL meter and a test tone disk and test to see how they measure. Don't forget to add in the corrective values to your findings to get an accurate indication of the measurements.
Good luck in you discovery,
D
Also, you could purchase a RS SPL meter and a test tone disk and test to see how they measure. Don't forget to add in the corrective values to your findings to get an accurate indication of the measurements.
Good luck in you discovery,
D