The signals captured by the array were outputted from the stethoscopes to 4 different
channels on the preamplifier and sent to the computer via the firewire port. The signals
were digitized by a Texas Instruments digital signal processor (TIXIO2200A), and placed
into the computer’s main memory. The signals were removed from main memory and
written to the computer’s hard drive by the developed software (using the MATLAB
language). Figure 11 illustrates the sound emitting, acquisition and processing instrument
with an unknown system as the measurand