a data processing process and embodiment for optimizing the signal path for multi - modality imaging is described . the embodiment and process optimizes the signal to noise ratio in a positron emission tomography signal path utilizing scintillation crystals , avalanche photo diodes , and charge sensitive preamplifiers in a dual modality mri / pet scanner . the dual use of both and analog pole zero circuit and a digital filter enables higher signal levels or a fixed adc input range and thus a higher possible signal to noise ratio in the presence of significant pileup caused by high positron activity . the higher signal to noise ratio is needed in the pet signal architecture , because of the presence of non - modal time varying electromagnetic fields from the mr , which are a significant source of noise for the wideband pet signal modality .