What should I expect from the "noise reduction" mode?

Hi All,

So far, I’ve had great results with speech in a quiet environment. When the noise goes up, it’s another thing altogether. In a restaurant I can hear people talking three tables away, just like they were sitting at my table. Left side, right side, in front and behind. It doesn’t seem to make any difference. Apparently there is no adjustment for only increasing directionality, and the more aggressive noise reduction settings just cause a hollow tinny sound to everything. What should I realistically expect regarding noise? Thanks.

Dag

Is this what you refering… this is taken from an article written by pamela souza

example is shown in Figure 3. Suppose this patient is at a restaurant. (For now, ignore other hearing aid features like directional microphones or digital noise reduction). Let’s imagine that his dining companion’s speech reaches his hearing aid microphone at a level of 70 dB SPL. Now suppose someone seated at a nearby table is also talking, and the speech of that person (who is further away) reaches the hearing aid microphone at 50 dB SPL. For the distant talker, the output level is 68 dB SPL (gain 18 dB). For the close talker, the output level is 70 dB SPL (gain 0 dB). Although the desired effect of compression—that soft inputs receive more gain than louder inputs—is maintained, the output difference between the distant talker and the close talker is only 3 dB so the patient may perceive those sounds as of similar loudness.

Figure 3. Input output function for a hearing aid set for a compression threshold of 45 dB SPL, and compression ratio of 6:1.

If this patient comes back for a follow-up and complains that the distant speaker was as loud (or nearly as loud) as the close speaker, we might lower the compression ratio (Figure 4). Now the speech of the distant talker receives 18 dB gain, for an output of 68 dB SPL. The speech of the close talker receives 8 dB gain, for an output of 78 dB SPL. Now the output difference between the speech of the distant talker and the close talker is 10 dB, so the patient will perceive the close talker as louder. These compression ratios are higher than would likely be used in the clinic, but the concept is the same: the higher the compression ratio, the more similar the outputs for sounds of different intensity. The lower the compression ratio, the more dissimilar the outputs for sounds of different intensity will be.

Figure 4. Input output function for a hearing aid set for a compression threshold of 45 dB SPL, and compression ratio of 2:1.

Hi xbulder

That sounds exactly like what I’m hearing. So it’s really an issue with compression. Curious. Thanks, I’ll talk with my Audi.

Dag

The aids referred above are all WDRC aids with compression.

There is another technology called ADRO, (wide) adaptive dynamic range optimization which solves this hearing in noise problem to some degree. This system analyzes the input sound and if it meets certain criteria increases or decreases the gain quite slowly. So all sounds maintain there relative real loudness.

America Hears.com is one of the few companies pushing this technology. I have used their aids and this system works beautifully provided you have a mild to moderate loss or even a severe loss. But, if you have a severe or profound loss you may have severe recruitment…if so the ADRO works so slowly that it allows sharp fast loud sounds to come through at full loudness which can be uncomfortable and cause masking of other frequencies. The America Hears aids do have a MPO/MOL (maximum output circuit) that instantaneously cuts out sharp transients but the problem with all this type of circuit is that those hoh with severe recruitment have such a limited dynamic range that they need to clamp down so far on the MPO/MOL that it starts to distort louder passages in speech.

You could try their aids at no risk as they have a 60 day 100% return policy. Ed

the adro, this is hansaton method- i believe it is the same thing as
the phonak choclear bionics or somehting right?

this is a concept it never caught up

Hi ed121

Right now, HearPO doesn’t offer products from America Hears. I can get Phonak, Rexton, Sonic Innovations, Unitron, Siemens and Vivatone. My Audi has experience with Oticon, Phonak and Widex. So right now, it looks like Phonak is what’s available. I need to talk with him about getting something outside of HearPO, but that may violate his agreement with HearPO. Don’t know yet, but am seeing him tomorrow and will ask.

It’s been frustrating. I get good speech improvement in quiet environments, but noisy locations are still a challenge. It’s like the noise reduction features just don’t work. Maybe if I tried an Oticon Delta (what he sells the most of), he’d be able to do a better job with the programming. This is my first hearing aid, so it’s difficult to keep reasonable expectations. I don’t have anything to compare to.

Dag

i think you could get an an audeo with similar results with the delta…

Or perhaps a Pulse or the Dot from GN should be an alternative

Check out “My eval Phonak SAvia vs Starkey 1200”. I found that the adaptive (digital) noise reduciton features ( one channel manual adaptive, other automatic) did not deliver the relief from noise as manufature promised. The Savia reduced speech along with the noise so was no help.The auto reduction was crazy making as both Savia and Starkey kept changing from mild to max reduciton every minute or so. (Starkey every 30 seconds) The Manual noise reduc channel in Starkey reduced noise to a reverberation that interferred with speech.

This digital noise reduc technology is in infancy and right now really doesnt give more ( or as much, in my opinion ) as the old mechanical directional mics. ( Two mics, one in fron, one in back. Push button back mic shuts off and you get 30 db reduc in sound back and sides.If noise behind you really helps with converation restaurants; also car.

Following XBuilder’s sugggstion am test driving two older gen aids with "mechanical " direcitonal mics (we really need standardize terms for these features) Widex Brava and Starkey Cierra. Both are BIG improvements in noise (for me) over current generation Savia and Starkey.

My Audi has had similar complaints from othe patients (not all) He feels at least, the manufactures should allow the auto noise reduction channel to be set to manual; so consumer could have one channel set in mild reduction and other mod or max permanent. (Yes he tried to do this , no avail)

I hope they stop with the bells and whistles and crazy nomenclature and start developing noise reduction that really works.

Dear Lucky man…
Some of the GN products allows you to customize how much noise reduction you want per program… the noise reduction can be set to be from 3db up to 10db… I believe the Pixel and the Metrix and azure can be program this way…

In addition, you can set the instruments so that they are always on omni,
or softswitching, adaptative directionality, etc…

you might want to consider perhaps a Pixel

Hi All

I had another adjustment last Friday, and I’m happy to say that I think we’re finally on the right path. Speech in quiet is still great, and I’ve finally seen an improvement in speech in noise. It’s much more “comfortable” now. Probably not a great way to describle it, but it no longer sounds like the whole restaurant is now sitting at my table. I can hear my companions, and everything isn’t drowned out by the ambient noise. Much better. He has one other idea, but wants to discuss it with the Phonak “trainer” first. Stay tuned. :cool:

Dag

deaR LUCKY MAN:

I have taken the time to check the aventa fitting software from resound…

for example, I have check the canta 7 modelo 780-d bte
you can customize the noise reduction per program (laser)

you can set noise reduction to be soft moderate and strong…
yes it can be done…

on top of the main fitting screen there are 3 taps, basic , restauran and change the 3rd one to party

on the center you see there will be the word LASER
if you click here you can set up how much noise reduction you want…

i think this is what you want…

THIS is a really old instrument… but i suspect you can get the same from
a pixel or a metrix…

Dag - If possible, please let us know what you’re audi did to adjust your aids for noise. I’ve got Phonak MicroPower V’s and am having similar problems in noise. I’m hearing too much distant sound and not enough of the sound I need to hear right in front of me. Thanks

Background noise is one of the biggest issues that people with hearing loss have and it is also one of the biggest issues that people who wear hearing aids experience. First off it must be understood that there is no such thing as a hearing aid that takes away all of the background noise. If somebody told you that, they lied.

Hearing aids can help in background noise but there certainly are limits. THE factor that governs understanding in noise is the signal-to-noise ratio (SNR). The signal is what you want to hear, the noise is anything else. In environments with very poor SNR (like a bar, sports arena, etc), no matter what hearing aids you have, you will have significant difficulty understanding (as does someone with normal hearing). Hearing aids can improve the SNR if the speech and noise are spatially seperated, that is the noise is coming from one direction and the speech from another.

There are several features that can be activated in the hearing aids when it gets noisy:

  1. Digital noise reduction- This is almost always based on a estimation of the SNR in a number of frequency regions (Channels). If the noise is louder than the (presumed) signal, then that channel is attenuated. For real-world environements, this doesn’t change your ability to UNDERSTAND. It really just makes listening more comfortable or easier.

  2. Directional microphones- This feature basically amplifies sound more in the direction you are facing and less for non-frontal azimuths. Premium hearing aids from a number of manufacturers use adaptive directional microphones that turn down in different directions depending on where the noise is coming from. Hands down, directional microphones have been shown to help in noise more than any other feature.

  3. Noise programs- Many hearing aids do this automatically, or can be programmed to a manual noise program. Usually this is a combination of the above two items, as well as reduction in the overall volume. That’s why sometimes it sounds like the aids are “shutting down” in noise. Some people love this feature, some don’t. The bottom line here is that it can be adjusted by a knowledgable audiologist. The frequency of occurrance and degree to which the hearing aids “shut down” in noise can be adjusted in the fitting software. Usually the “noise program” includes the activation of the directional microphones (if available), an increase in the digital noise reduction, and a reduction in the overall gain and or output.

I hope this helps and isn’t too overwhelming. The bottom line is… in a very poor SNR, you will still have trouble. Directional microphones will help in noise. Digital noise reduction is there to make the environment more tolerable.

Hi Lucy

Not being a professional, I don’t know the details of the fitting software, but his comment was that he made an adjustment to the speech in noise program only (didn’t effect other programs) to reduce the input from the sides and focus more in front. Perhaps one of our resident professionals with Phonak experience can help guide your Audi. The speech improvement in quiet has always been good, and now noisy situations are much better as well. I was considering turning these in and trying something else, but no longer. I go back to see him in a couple of weeks, and I’ll ask what he did, but you may be able to get an answer here faster. Good luck.

Dag

Hi Lucy

One other thing: Take a look at the second post in this thread (from xbulder). He references a problem with the way compression is set up that could also be part of the problem.

Dag