In the picture to the left, notice a small piece of hardware between the computer screen and mirror.  The patient's hearing aid and computer software are interfaced through this hardware using specially designed cables.  The  main advantage is that with today's digital products, more fine tuning can be incorporated into the patient's hearing aids.  The disadvantage is that for any modification to be made, the patient must be hooked up to the audiologist's computer. 

• Multiple Programs: Two to four separate programs that are appropriate for different listening situations can be loaded into the device. For instance, the user can use one program for listening in quiet, another program for listening in a background of noise, and a third program for speaking on the telephone. Switching from program to program can be done by means of a remote control or with a toggle switch or push button on the instrument.
• Wide Dynamic Range Compression: A major problem for people with sensorineural hearing loss is discomfort as a result of changes in sound intensity. Typically, patients' tolerance for low-frequency sounds is different than their tolerance for high-frequency sounds. By accounting for these differences, digital/programmable hearing aids can be set so that low-intensity sounds will remain audible, moderate-intensity sounds will be comfortably loud, and high-intensity sounds will be loud but not uncomfortable for all frequencies.
• Reduction Of Background Noise: By using two separate microphones, one facing toward the front and the other facing toward the back, hearing aids can effectively minimize distracting noise from the back while emphasizing the desired signal from the front. This has been one of the most substantial advances in hearing aid technology, because it directly addresses a common and difficult complaint of patients with sensorineural hearing loss: listening in a background of noise.
• Feedback Suppression: Because a hearing aid does not create a perfect seal with the ear canal, some of the amplified sound will travel around the shell and escape into the air. Under certain circumstances, for instance if a hand is placed over the aided ear or if a telephone is placed on the ear, this escaping sound will be reflected back into the microphone of the hearing aid and be re-amplified. As this continues to occur, acoustic resonance occurs which can produce an annoying whistling sound. Digital hearing aids are able to sense when this feedback will occur and will automatically compensate for the unwanted sound so that feedback occurs much less often. This is one of the most important advantages of digital hearing aids.
• More Natural Sounding Perception Of One's Own Voice: Most people who are new to wearing hearing aids comment that their own voices sound different to them. This often occurs simply because something has been placed in the ears. For instance, just covering your ears with your fingers will probably give you an echo-like perception. Several manufacturers have developed hearing aids that can be fitted with only minimal occlusion of the ear canal so that your own voice sounds more natural. This kind of fitting typically is limited to people with high-frequency hearing loss but normal hearing in the low frequencies.