Fitting SW protocols / Rationales

My Audi recently switched the programming of my Bernafon Verites from Bernafit NL to NAL-NL1. Looking at the gain reports it looks like the Bernafit NL did less amplification for the low frequencies than the NAL-NL1 but I had problems with feedback in the higher frequencies with Bernafit. Tried tulip domes but was uncomfortable in my right ear likely due to a narrower ear canal. NAL-NL1 settings better with regard to feedback but other changes were also made so I am not sure if that was the reason. What is the difference between the different fitting protocols Bernafit, NAL-NL1, and NAL-NL2? How is the Bernafit supposed to be better?

Hearing aid companies create default fitting rationales, or prescriptions. Each company has their own formula. These formulas that prescribe the hearing aid gains are generally intended to assist new hearing aid users in accepting the quality and loudness of listening to amplified sound.

NAL-NL1 and the newly developed NAL-NL2 will tend to be louder than the company’s formula. The NAL-NL2 formula is new and brings many improvements to the older NAL-NL1. Some of these improvements relate to the age of the listener, the amount of hearing loss, and gender. NAL-NL2 is a work in progress for most hearing aid manufacturer’s and not widely available.

MedRx has recently made available for download REM software version 2.8, which includes NL-2. I find Phonak’s target matches these targets pretty much exactly.

I believe only siemens has NAL NL2… Other should join soon

Siemens had a window of time where they were the only company with access to NAL-NL2. MedRX has now implemented NL2 as well. I’ve done a few cross check’s against the NAL-NL2 standalone and their target generation looks fairly accurate. The other manufacturer’s will probably follow suit in software releases this spring and summer.

IIRC it wasn’t that far from the Medrx target ‘box’ anyway.

Generally NL2 targets aren’t drastically different from NL1 but the logic behind NL2’s target generation is much improved. Some patients will find NL2 to be slightly quieter than NL1, which is a welcome change.

The presentation hosted on NAL’s website does an excellent job of introducing NAL-NL2. http://www.nal.gov.au/nal-software_tab_nal-nl-2.shtml

Somebody mentioned about it being a bit less harsh. Probably less influence on the research now from over-amped analogue wearers.