sda-srs crossover mod

You could probably achieve what you want by an external 2 way DSP crossover and change the internal wiring accordingly to disconnect the original crossover. The crossover point is around 2000 hz. Done correctly would probably result in a pretty good loudspeaker. But it won’t be a Polk SDA speaker anymore. There’s more to the crossover than the SDA crosstalk elimination. If you got one of the larger speakers the tweeter part of the crossover is quite complicated and I would not tinker with it. Even if the speakers are old they’re very well engineered even by today’s standards. What you refer to as crosstalk is exactly the opposite since it’s out of phase and thus eliminates (lowers) crosstalk for better stereo imaging. Just as your noise cancelling headphones eliminate noise by playing the surrounding noise out of phase.