Another issue is wether you use an inline filter to roll off low frequencies to the midrange drivers. If you use this filter, which goes between the preamp and power amp, the midrange drivers can play louder and cleaner since they don’t have to deal with low frequency energy. However, this also means anything else connected to the power amp’s speaker binding posts will not get the low frequency signals, like subwoofers using high level connections.
So if you are going to use an inline filter for the midrange, you have to use line level on the subs from the preamp or whatever you are using as a master volume conrol.
Mike