How does Speech Rescue work, and how does it differ from other frequency lowering technology?
Speech Rescue is Oticon's approach to frequency lowering. We have seen other approaches to frequency lowering in the market that are not consistent with our philosophy of getting the most from the speech signal.
We believe that many patients with a severe or even severe to profound hearing loss have better capability in their auditory system than is utilized by these other systems. There has been a movement in the industry of not providing direct amplification, especially in the mid to high frequencies.
Our approach at Oticon has always been to provide as much information from the speech signal as is possible for patients. We understand that for some patients, frequency lowering is an important option and we’ve created a very good solution for that.
Speech Rescue works with Speech Guard E: Speech Rescue captures high frequency information and reproduces it in the mid frequencies, and then Speech Guard E places it in the remaining dynamic range of the patient in a way that preserves as much detail as of the speech waveform as possible.
One of the most popular frequency lowering approaches in the marketplace is frequency compression, where a broad range in the high frequencies is compressed into a lower frequency range. This approach takes a very broad part of the speech spectrum and forces it into a smaller part of the lower to mid frequency spectrum. At the same time, the high frequencies are typically abandoned. There’s no attempt to provide amplification in the highs.
What differentiates Speech Rescue from frequency compression is that we do not compress anything in terms of frequency. We present a full bandwidth including the high frequencies and at the same time, identify particular sections of the bandwidth where the patient might be at risk for misperception because of a lack of audibility or a lack of usability.
We copy that information and replicate it very carefully in the mid frequencies. We call this approach “copy and keep”, because we don’t abandon the high frequencies by default. We keep the high frequencies, while copying that information in the mid-frequencies where there is generally better function.
We just don’t believe that for any individual patient you know for sure whether or not they can use high frequency information effectively. So, we leave it in, but copy the important information and reproduce it in the better functioning mid frequency range.