Check page 12. Yes it has boost. It helps the low end of the THT bringing up the response some where the THT falls naturally. Experiment with both the SS filter setting and the parametric EQ to get best freq response and lowest distortion. I use the 16Hz setting. If you want to push the hell out of the THT, use the 20 or 25Hz setting. Excursion maximum should be around 20Hz for THT. The 25Hz setting should allow you to push all kinds of power into the THT for max output. I sacrifice output for extension in my setup, I get good ouput into the high teens that way at 10dB below reference (above this level, my mains complain some, they are the limiting factor in my system).