When you choose the "style" option for ACMP,
the bass and the pad you are hearing are the same sounds of the bass channel and the pad channel of the style you are currently using.
Mixing Console(style part),then press C and then 3 for bass channel's sound and 6 for pad channel's sound.
On my s750 for the fixed option it has a "finger bass"(GM & XG folder) and I think a live! strings voice for pad sound.