Analog vs Digital

In a land where technology reigns supreme, hearing aids are no exception!  After I explain hearing aid benefits to patients, so often I am asked of the hearing aids, “Are they digital?”  These days, the answer is a resounding “Yes”.
What is the difference between analog and digital hearing aids?
Analog hearing aids were what were available for many, many years, up through the late 1990s and early 2000s.  Analog hearing aids take an incoming sound wave and amplify it so it’s louder, but unchanged.  They can have screw settings called “trimpots” on them so that the sound can be slightly modified or adjusted.  They can also have volume controls on them as well.  Otherwise, the sound and sound quality remain relatively steady and unchanged.
Long term analog hearing aid users can have some difficulties switching to digital hearing aids, as they are used to the analog sound and they perceive that the aids sound “louder” than digital hearing aids.  It can also be an adjustment for long term analog hearing aid users to get used to hearing soft sounds again after having worn analog aids for a long period of time.

 


Digital hearing aids, on the other hand, have a computer chip in them that take the sound and convert it to a digital code.  The digital aids have multiple adjustable channels and bands, like an equalizer on a stereo.  Each channel or band can be used to adjust compression and/or gain in the frequency range of the channel.  Wide Dynamic Range Compression (WDRC) is the way that the instrument gives different amount of amplification to different sounds; ie soft sounds are amplified more than regular sounds and loud sounds are not amplified at all and can be compressed.  The amount that sounds can be compressed or amplified, as well as the level at which compression is activated can all be adjusted in a digital hearing aid.   Gain refers to the amount of loudness or amplification we give the input signal or sound that you hear.   Much research shows that WDRC is the primary way to maximize speech intelligibility, making very soft sounds audible, conversation comfortable and understandable, and loud sounds tolerable.
Digital hearing aids have also introduced “extras”, like directional microphones, noise reduction, accessories like remote controls, Bluetooth compatibility, etc.  One of the most-touted features of digital hearing aids is their flexibility and the amount of adjusting that can be done in your hearing healthcare professional’s office by simply hooking your hearing aids up to the computer.  Hearing aids can be programmed and reprogrammed in a number of minutes if you don’t like the way something sounds or if your hearing loss should change in the future.
The vast majority of hearing aids on the market today are digital, not analog.  The same hearing aid is not right for everyone, and there are those who prefer an analog sound to a digital sound; in my experience, the people who prefer that are long term wearers.  Do not be surprised if you are not offered analog technology at your next appointment as very few manufacturers still produce an analog aid.  As I said before, hearing aids are no exception to the rule when it comes to technology…it really has changed our industry in a profound way.
Until next time,

 

Dr. Kristin