If someone has 70db HL and gets 70db HA gain, does he hear 0db?

To answer your question simply, no.

The reason behind this is sound mapping. For arguements sake lets take a "normal hearing" person with 0db loss from 1Hz to 20kHz. If you present a varied signal to the person that is has sounds across all frequecnies upto 120db you are working with 120db dynamic range.

Now take a person with 70db HL and try to amplify the same sounds so that the person is able to hear them. The person with 70dB HL only has 50dB dynamic range. This means all sounds have to be mapped to fit into 50dB dynamic range. Since you are compressing the dymanic range, it won't be the same.

The answer of coarse is much more difficult than this but you really would need to understand the sound processing technology behind hit for it to make complete sense. Most high end hearing instruments use both expansion and compression to supress noise floors and fit the entire range into the dynamic range of the person wearing them.

C1
 
CrazyOne said:
To answer your question simply, no.

The reason behind this is sound mapping. For arguements sake lets take a "normal hearing" person with 0db loss from 1Hz to 20kHz. If you present a varied signal to the person that is has sounds across all frequecnies upto 120db you are working with 120db dynamic range.

Now take a person with 70db HL and try to amplify the same sounds so that the person is able to hear them. The person with 70dB HL only has 50dB dynamic range. This means all sounds have to be mapped to fit into 50dB dynamic range. Since you are compressing the dymanic range, it won't be the same.

The answer of coarse is much more difficult than this but you really would need to understand the sound processing technology behind hit for it to make complete sense. Most high end hearing instruments use both expansion and compression to supress noise floors and fit the entire range into the dynamic range of the person wearing them.

C1
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What happens if that person just wears an analog HA or a digital with every feature disabled? Would the reciever/microphone on the HA be capable of detecting a 0db HL(which does NOT mean 0db SPL) sound and properly amplify that? I am trying to find out the maximum possible aided scores depending on the extent of hearing losses. Is it as simple as reading the specifications for max gains?

I did notice that max gains is based on a 50db SPL input sound. I am wondering if this is one reason im not quite getting max gains? In the lower frequencies, the input sound could be 25-30dba(A weighing) would the HA still be capable of outputting the same gains as a 50dba sound? If not, this of course puts a floor on my absolute aided hearing. My audie said 15db aided is realistic but not 0db! Ive never seen anyone get 0db even with CIs for the matter.

As for dynamic range, doesn't the UCL and pain threshold increase somewhat with more HL? For a hearing person, discomfort is experienced at 90 to 115db but I don't experience discomfort till around 130db. Also see my long reply to you in the other thread.
 
john57 said:
Steve,

I believe that the lowest db that the implant will start to start sending stimulation is heavily depended on what the sensitivity control is set for. The sensitivity control tells the implant what db level of sound before the external processor will send to the implant. One CI moment that I had was able to hear a piece of paper failing on to a carpet floor. I must be hearing at a low dB level. I am not sure if the 25dB is the lowest hard limit that the CI Implant can start stimulation since I have seen for some at certain frequencies can do better that 25dB. Some day I will confirm what the lowest dB level that the implant can start sending stimulation but on my implant I use the sensitivity at 8 which is far from the maximum setting that the implant can start stimulation but that works for me most of the time.
Click to expand...

I can hear the paper floating down to the floor but not the whole way down...just at different points where the paper turns around in the air and also when it hits the floor. I actually just tried this just now. And I have the sensitivity set to 0.
 
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