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RE: OK now I am totally confused...

First of all, neither Ralph (I am sure) nor I want to take the responsibility for what might happen as a consequence of any of these mods. So, neither he nor I want to be on record as advocating anything that goes against the advice given by Sound Lab (i.e., Dr. West) regarding the use of their speakers. I can only tell you what I have done, at my own risk, to my speakers, and what the results were. Dr. West is on record as stating that it is not "safe" to remove the parallel resistor that comprises part of the hi-pass filter in front of the SL toroidal treble transformer. Dr. West stated that in part that resistor is in place to protect the toroid against musical transients that might damage it. In practice, I can tell you that I and a few others did remove that resistor; in my case I also changed the value of the capacitor from 36uF (factory) to 22uF. (I did this while I was waiting for the Australian transformers that now completely replace the toroid to arrive at my home.) The reason I reduced capacitance from 36 to 22uF is to preserve the crossover point or the "knee" of the hi-pass filter at about 550Hz. That is the factory-implemented crossover point when the resistor is in place. I calculated the value of 22uF based on measurements made with my own relatively new 845PXs. (Ergo, I cannot guarantee that this is the best value for anyone else's speakers.) I can tell you also that there was a big improvement in sound with the resistor gone and the capacitance at 22uF, and there were no ill effects on the toroid. If you were to remove the parallel resistor and NOT alter the capacitance, then the crossover point would be at a lower frequency (~350Hz). This, IMO, increases the risk that the toroid could be damaged; it was not designed to handle extreme low frequencies. Proceed at your own risk.

One mod I can recommend unconditionally is the removal of the "Brilliance Control", which is anything but. If you have not done that, try it.

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