" I see by one of the provided spectrums the 1X (975 cpm) is about 2.45 mm/sec for the same measurement point. The overall is 6.072 mm/sec and there is a substantial amount of higher frequency above 5 kHz."
That is why I questioned the value of balancing! Some of the OP numbers could be filtered 1xSS or overall levels. I will wait for the OP to clearify the balance numbers with 1xSS amplitude-phase and overall level for each measurement point and each configuration.