What type of limiter is in my amp and how does it work?

The limiter found in the Bass 350™, Silverado™, SM-900™, Workingman's^®, WorkingPro™, and the X-Series is a soft-knee type limiter. The circuit is located after (post) the master volume and before (pre) the power amplifier. The circuit is driven by the master volume control. It's threshold (starting point) is preset by the factory so that the user can get maximum overall apparent volume without unduly overdriving the power amplifier. The limiter in the older SM-400 and ST-220 differs according to its position in the circuit and the fact that it is continually adjustable.