Can I use an L-pad before series crossover

Hi. I ve build Tony Gs Andromeda’s Unfortunately my bass driver ca26 only measures 88.5 dB not stated 90.5 thus sounds a little thin. Is there a way of attenuating entire mid/tweeter series section in this 2.5 way design ? Could I use L-pad before the crossover? I wanted to attach a schematic but don’t know how so you may have to look it up sorry. Thank you all for reading