preamp vs external crossover audio level control

[bldozier]

Hi,
The pioneer sa, intergrated amps bass and trebile, are these controls set to netural if using an
Eternal sf850, or d23 external crossover. Would the crossover do the adjustment here and the preamp
Basically do just balance control, with filtering.

[bldozier]

Here are the
Pioneer spec 1, sa9500, and 9500II,
With the spec and 9500II having netural (0) controls, and the 9500 and its
turn over control, but no zero setting in the turnover section, I bought a tx 9500 so
The sa 9500 for the preamp section was the choice,

66061
66062
66063

So I would set the preamp section to 0 and use tbe external crossover,
66064

What about in the case of the sa9500?