One of the most important parts of a digital audio system (but often overlooked or taken for granted) is the stability of the master clock. Since various manufactures make different manufacturing decisions, usually based on their economic needs, the quality of an internal clock in many converters leaves something to be desired. Happily a solution is possible so long as the device in question can synchronize to an external clock.
The Big Ben is a dedicated master clock source using Apogee's new C777 clock. Unlike the general implementation of the phase lock loop (PLL) that uses a combination of analog and digital elements, the C777 clock utilizes an entirely digital process, developed using the most advanced Direct Digital Synthesis (DDS) technology along with DSP based digital filtering. This allows the unit to intelligently manipulate incoming signals and adapt to them accordingly delivering the most aggressive jitter reduction ever.
Adaptive Loop Filtering (ALF) maximizes Big Ben's clocking ability with an intelligent low pass filter. Because the C777 has made all incoming signals into data (1's and 0's) the unit is able to dynamically compensate for excessive jitter and even improve already acceptable clock signals to levels unattainable until now. No matter what the input looks like, ALF can adapt and overcome all obstacles to create a stable, reliable, low jitter clock source.
Additionally, SureLock ensures that even if the unit encounters the ultimate disturbance in clocking, a dropped signal, it will compensate by remaining locked on the last relevant frequency sent by the delinquent device. When the signal resumes, Big Ben will gradually, and smoothly re-synchronize without interruption. The unit also provides the option for real-time digital format conversion.