Ask the Audiologist

Starkey AXENT Hearing Aid

February, 2002. Starkey Laboratories, America's largest hearing aid manufacturer, introduced the line of Genesis digital signal processing hearing aids, The Axent is the leader of this line.

The Axent allows the audiologist to adjust the amplification in 4 different frequency bands (or channels), and to adjust the edges of each of these frequency bands. It allows the audiologist to further refine the frequency response of the hearing aid in 8 smaller bands. Further, it allows the audiologist to select the directional response of the directional microphones from three different patterns.

The main new feature of the Axent hearing aids is their ability to differentiate speech from noise. The Axent uses a Starkey Labs patent-pending method to determine whether the incoming signal is mostly speech or mostly noise. It estimates the speech to noise ratio and adjusts the response of the hearing aid accordingly.

The Axent noise management algorithm reduces the gain in the channel (frequency band) in noisy situations where the speech to noise ratio is poor. That is, the amplification of the hearing aid is reduced when the noise becomes much louder than the speech. As the ratio gets worse, the gain is reduced further. This allows a noise that affects just one or two bands to be reduced while the speech signals in the other bands come right on through! The result is an amazing improvement in the patient's ability to understand in a noisy situation.

The Axent also uses multi-channel expansion to reduce quiet background sounds that some hearing aid wearers find distracting, like computer fan noise or refrigerator motor noise. The Axent monitors this background noise in each of its channels to selective reduce this type of noise without affecting the other channels.

The Axent has an active feedback cancellation system that monitors its output, listening for feedback, and adjusts the feedback filter to subtract the feedback signal from the input.

The Axent has three memory positions that can be set to the user's preferences. The memories are selected by a push button on the face plate. The Axent is one of the few hearing aids that has room on the CIC case size for the push button, allowing memory changes even in the smallest, nearly invisible, CIC hearing aids.

Other options include an "automatic" telephone coil switch, which turns on the T-coil when a telephone headset is brought near the hearing aid. This is helpful for people who don't want to be bothered by having to push a switch to turn on the T-coil (We have had people report that their hearing aid was dead, when it just was set in the T-coil position--this would prevent that kind of mistake.)