If those are stepped attenuators, isn't having only 5 positions leave some big jumps from one setting to the next? I suppose that the preamp will take up some of that. That's the one thing I didn't like about the Pro 700's. But setting the attenuators on the amp to about the 2-3 O'clock position and then using the pre made it just right. I also used a regular PL-700 pot on them in some cases.
not sure if they can work