@jon_5912, That’s not quite correct. They’re spec’d at:
90 dB at 2.83 V 1/m
not
90 dB at 1Watt 1/m
You need to drop the sensitivity by 3dB for each halving of impedance below 8 Ohms.
I don’t know what amp you are using to drive which speakers, but it’s not uncommon for an amp to halve it’s Class A output as it doubles it’s output with each halving of impedance.
90 dB at 2.83 V 1/m
not
90 dB at 1Watt 1/m
You need to drop the sensitivity by 3dB for each halving of impedance below 8 Ohms.
I don’t know what amp you are using to drive which speakers, but it’s not uncommon for an amp to halve it’s Class A output as it doubles it’s output with each halving of impedance.