This is the schematic of the 7-pole LPF used in the QRP Labs 40-meter LPF:
The plot from Elsie 2.77 for the above filter looks like this:
The actual SA response curve looks like this:
The curves are remarkably similar. Knee around 8.8 MHz, about 36 dB down at 14.08 MHz. Loss at 7.04 MHz is a bit worse on Elsie, but that is based on Q values of 40 for the coils and 200 for the caps — both are probably a bit better.
