LP caveat was to have ten ft at least from the spkrs.@blindjim I sit closer than 10 feet; they work fine if you're sitting down (this is all about the tweeter blending properly). You need to be 10 feet or more only if standing up. The power supplies are simply set to a particular current to energize the field coils and then left alone.
And I never delved into what or how the adjustments on the driver’s power supplies or other controls accomplished or why?
My speakers are the T-3s and IMO/IME they have bass very similar to that of the T-1s; the T-3 cuts off at 22Hz instead of 20Hz, but I had John make my T-3s a bit taller so they would cut off at 20Hz :) the mids and highs are nearly identical.