intactaudio
I looked up L-Pad, I see what you mean about 2 stages to maintain impedance shown to the crossover (or amp).
https://en.wikipedia.org/wiki/L_pad
The original electro-voice AT37 Attenuator was indeed an L-Pad, maintaining a 16 ohm load to the crossover. (AT38 was the 8 ohm version)
I remember it having the dual 'stacked' design.
https://products.electrovoice.com/binary/AT37%20and%20AT38%20EDS.pdf
I replaced them years ago with 16 ohm L-Pads, (also dual stacked design) the ones I just removed, I still have them. The speakers sound awful without them.
When I wanted to put level controls back in, why not new? I searched and found the ones I ordered, not understanding about constant impedance shown to the crossover.
They do seem to be a single resistance design, thus they would vary the impedance shown to the crossover, thus affecting the crossover frequency. Their screw terminations mean I can avoid solder, try em, keep or return them.