Ask the Audiologist

Widex Senso Plus™ DSP hearing aids

As you know from our article on digital signal processing hearing aids, Widex was one of the first companies to offer digital signal processing hearing aids. Their circuits have proven to be very popular with our customers over the years, even with the increased competition presently on the market (some offices sell over 16 different brands and models of dsp hearing aids, and the number keeps increasing).

Since Widex first introduced the Senso, they have added models including ones with directional microphones, telephone coils (for non-CIC models), power circuits for severe hearing losses, a non-automatic model with a volume control (P series), and BTE models in colors (beige, brown, gray, red, yellow, blue, green, and black).

They also released the Senso Plus™ circuit. The Senso Plus uses the same basic digital signal processing ideas, but adds several new features. To refresh your memory, the basic Senso has three independent channels for sound processing, uses time domain processing to disquingish speech from noise, selectively reduces noise signals, has automatic feedback control, and is completely automatic in operation.

Sound Stabilizer™
The Sound Stabilizer brings the hearing aid gain back to normal more quickly after a long lasting burst of sound. This means that dynamic changes in signals sound more normal to the user.

Speech Intensification System™
The Speech Intensification System listens for speech signals in the presence of noise, and will automatically boost the amplification in the frequency most important for speech intelligibility, while reducing the gain at the frequency containing the noise. This system reduces the masking effects of noise on speech. Widex found in laboratory tests that this resulted in a significant improvement in recognition of monosyllables as compared to Senso (not Plus) in both party and car noise situations.

Automatic Output Control
This AOC circuit limits the output in high signal and high gain situations to avoid clipping. This will reduce distortion in loud music and other situations where there might be overload of the circuits.

Extended Dynamic Range
The Senso Plus now can process input signals up to 100 dB SPL linearly, without saturation or temporal distortion. Many digital hearing aids compress the input signals into an 84 dB SPL range, while the Senso Plus can handle signals up to 110 dB SPL without significant distortion. This is a tremendous improvement for music and other high dynamic range signals.

Widex improved the cellular telephone immunity with the Plus circuits. (Phil's comment: "I must say that I have worn Senso CIC hearing aids for years and have used a variety of cell phones, including digital ones from Cellular One and Bell Atlantic, without any interference or feedback.")