In recent decades, chatter has been a complex phenomenon facing machining industries. Although several toolholder manufacturers attempting to enhance the potential of the chatter-free boring process, numerous obstacles and downsides are challenging their efficiency. This study aimed to discover the sources of the unpredictable behavior of anti-vibration toolholders with a focus on SECO Tools' Steadyline boring bars. We used experimental modal analysis (EMA) and analytical modeling to detect the sources of nonlinearities and efficiency limitations. Understanding the system's dynamic behavior can help to improve the existing products and provide new technological solutions