I realize this is a long-shot, but figured I might as well ask. I just traced the circuit of my Weber Mass 200 attenuator: Note: this is the basics of the circuit, but I left out the line-out portion of the circuit for simplicity-sake. On the website, Weber says that this attenuator can work with 4 ohm, 8 ohm, and 16 ohm amps due to impedance swamping. My question is, is there some mod I can do to get it to work with 2 ohm amps? A bunch of other Weber attenuators that feature impedance switching seem to accomplish this sort of thing by putting a big resistor of 2 times the desired impedance going to ground right before the dummy speaker coil. This is the schematic of a different Weber attenuator, the Mass 100, which uses impedance switching, not swamping: So what if I put in a switch to switch in a 4R 100w resistor in parallel to ground right before the dummy coil in my Mass 200? Any chance of it working? Or would I blow out my amp's transformer?