EAS is the combination of two technologies, each responsible for a specific frequency range. Here is how it works:

• A cochlear implant converts everyday sounds into coded electrical pulses. These pulses stimulate the auditory nerve. The brain interprets these signals as sound.
  
  1. High frequency sounds are picked up by the microphone of the DUET 2 Audio Processor and converted into a special code.
  2. This code is sent to the coil and is transmitted across the skin.
  3. The implant interprets the code and sends electrical pulses to the electrodes in the cochlea.
  4. The auditory nerve relays this signal to the brain.
• Acoustic amplification turns up the volume on the sounds that the cochlea is still able to hear. For EAS, only the low frequencies are amplified.
  
  1. Low frequency sounds are picked up by the microphone and are digitally processed and separated.
  2. Sounds are amplified by the loudspeaker located in the ear hook and relayed via the ear mould to the ear canal.
  3. Sounds reach the undamaged areas of the cochlea responsible for processing low frequency sound.
  4. The auditory nerve relays the signals to the brain.