It helps a lot! My current Phonak V90s were fit with Adaptive Phonak Digital, which I’d bet is an attempt to maximize the proportion of new users who evaluate their first HAs as acceptable or better. But I’m going to switch to the Costco KS9 or possibly Marvel M90 very soon, and based on your description I’d say I’m an NAL-NL1 candidate. I’ll be interested to see how my Costco HIS reacts to that suggestion tomorrow.
What I typically do for my Phonak fittings (or most HA manufacturers), is I run Real-Ear at 100% adaptation level in the manufacturer’s proprietary algorithm. If it is not too far off of NAL-NL1 targets, then I will leave it in the “Adaptive Phonak Digital” settings, but adjust gain to hit NAL-NL1 targets. If the Adaptive Digital settings are eons away and it’s going to take a huge amount of tweaking to get it to hit NAL-NL1, then I will straight up change it from “Adaptive Digital” to “NAL-NL1” settings, which should get me closer. I keep a close eye on my compression ratios though. You don’t want them to over 1.8 (and definitely not over 2.0 or you can get some distortion with sound quality). Some providers may run REM, but that does not mean that they necessarily use the formulas to hit targets. Or that they’re proficient at adjusting the devices. And hearing aids are only as good as the person who programs them. So, my advice to you is: shop for a provider, not a device. You can buy a hearing aid just about anywhere these days. But you want to get a provider who really knows what they’re doing when it comes to programming. Best of luck to you!
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I don’t have the Target software so can’t model the Adaptive Phonak Digital for you. Here are some of the others. What I find is that these prescriptions cannot really be generalized that much. They “react” differently for different losses. What the formula does for you can be quite different that what it does with a different shaped loss.
NAL-NL1: This formula is the earlier version of NAL-NL2. As you can see the low frequencies are attenuated somewhat, while the midrange has the most gain. It also has the most compression, which is the difference between the top (soft sounds gain) and the bottom line (loud sounds gain). The high frequencies are kind of rolled off and have no compression. You may hear that as a loss of the detail and the air, as you need a fair bit of gain there.
NAL-NL2: This is the updated version, and is more commonly used. Notice that it is a smoother gain across the whole frequency range from 500 Hz up. There is also a lot of compression used from 500 Hz up. This one should sound more lively and brighter than NL1 in my opinion. It can be set for child or adult, as well as for tonal and non tonal. Tonal is apparently used for those speaking Asian languages where the same sound at different frequencies apparently has a different meaning.
DSL v5: I have to disagree a bit with DrLaura on this one. While it was originally developed for children it has been updated a long time ago to have a correction for either children or adults. It is currently on version 5 of the updates. This one has a steady increasing gain vs frequency with the most gain of the three at the highest frequencies, It also has the least compression. Soft sounds are not going to be amplified as much, and loud sounds amplified more, although the compression reduction is more on the soft side of the normal sounds.
I have an appointment at Costco for next Friday and I am going to give DSL v5 a try. I am currently using the Rexton proprietary SmartFit which is fairly similar to NL2. It is pretty good, but I am annoyed by distant sounds seeming to be too loud. For example if someone flushes a toilet in the bathroom down the hall, it sounds too loud to me, and competes with normal sounds in the room I am in. It may be a big bust, but I am going to give it a try.
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“Shop for a provider” is certainly the consensus top advice among pros. But it’s tough: how to do this shopping? E.g., how do I interview a variety of Costco fitters, and what do I ask them? (Costco has a huge price advantage. I guess I could think about spending 300% [$4,500] more for a top-notch provider if I could find one.) After tomorrow’s Costco appointment I do have appointments on Mon. and Tues. with independent providers; if I’m persuaded (somehow) of their competence relative to the Costco one’s I hope one of them will accept an unbundled deal. Bundling (charging $5000+ for a pair of aids with lifetime service) makes no sense to me; I might move hundreds of miles away in a year.
And back into the weeds… why start your Phonak fittings with the proprietary algorithm and then use NAL-NAL1 standards to adjust or evaluate it? Why not just start with NAL-NAL1?
I frequently have adult patients using DSL 5.0, but most of them are patients who have had hearing loss identified in childhood and have been hearing aid users for years. It can be very difficult to transition these patients out of the DSL algorithm once they are grown (they don’t want to suddenly stop using DSL just because they turn 21). So, I did not say that DSL cannot be used for adults, but it is the algorithm most commonly used and widely accepted for hearing aid fittings for children.
A good place to start when deciding on a provider would be to find out if they follow evidence based practice and follow best practice guidelines. Dr. Cliff has a great checklist available on his website. It can be found by following this link here: https://assets.website-files.com/5d9aadca574a7d240f2c7327/5dc22dcb06c33a18fd9fe31d_Dr.%20Cliff%20AuD%20Network%20Best%20Practice%20Checklists.pdf
Paying more for hearing aids only makes sense if there is more value added to what the provider is offering. I agree that bundling does not make much sense for most patients, which is why my own practice is unbundled. I practice in Florida, where a great number of my patients are tourists or snow birds, so when creating my practice model, I really could not justify charging for potential appointments that most of my patients were never going to be able to take advantage of. My prices for the aids are based on what manufacturers charge me, and the cost for my service depends on the time and complexity it takes to perform the task.
I’m afraid that the easiest explanation I can give you is that programming hearing aids is both an art and a science. It takes years of study to understand the science, and years of experience to understand the art. Every patient is different and may require me to approach their fitting from a different angle to achieve the desired outcomes. One standard from which I will not waiver though, is in running Real-Ear itself. I have to know what the desired target is, in order to move the patient towards hearing to the best ability of which they are capable. You may find that many professionals differ in their approach to programming, but one fact will remain the same: currently, there is not a way to accurately, independently verify what is happening in the patient’s ear canal without running REM. So, if you fit hearing aids without Real-Ear measurements, then you are just guessing that the device is doing what the patient needs it to do.
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There is a huge difference in the prescription when you click the Child button. instead of Adult. Adds way more gain, and compression. It may be the result of other issues. I’m guessing that most children do not have the high frequency ski slope loss like us old guys. Perhaps the Child formula is not intended to deal with a ski slope loss.
@Dusty directed me to the Phonak Target 6.1 software, and while I am still fumbling around with it, here is what I see as a first fit with Adaptive Phonak Digital, M Receiver, and Power Domes. The dashed magenta line seems to be the feedback threshold, and the recommended gain puts you into trouble at high frequencies. It would seem that custom molds would be in order. In comparison to the previously posted prescription formulas the Adaptive Phonak Digital seems to be most similar to NAL-NL2. Smoothly increasing gain from 500 Hz with quite a bit of compression. I checked what optional programs are available, but it just shows the Marvel M90 ones as I do not have the KS9 connected. To see what the KS9 offers I assume you would have to have a pair connected to the software.
And, I see that by default the Target 6.1 wants to use frequency compression. I would discuss the pros and cons of that with your fitter. I wouldn’t do it. The ideal way would be to try it with and without.
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Child targets are about 7 dB higher (on average) than adult targets. Children cannot use top-down processing to fill-in-the-blanks like an adult can because they have not learned language, so DSL child targets were developed to maximize auditory access. If a provider were trying to transition someone out of child targets and into adult targets simply because they had grown up, that provider would likely be ignorant of the history behind the development of the different precriptive targets. Adult targets aren’t lower because it is better for them to have less gain, they are lower as a compromise for what people will generally tolerate. While there are certainly a bunch of caveates to this, so long as hearing aids are not set at a damaging volume, users who can tolerate more gain generally do better than users who cannot.
People think of DSL as “pediatric” because it was developed first as a pediatric target, and because NAL does not have pediatric targets so if you are fitting kids you have to use DSL. DSL adult targets are just as valid as NAL adult targets; the basic ideals behind the fitting rationals are just slightly different.
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The Connexx software does have a Child setting for NAL-NL2. It does seem to boost gain about 7 dB, and increase compression.
I’m curious what factors you consider when deciding between DSL and NAL? Are there certain types of audiogram that you consider more suitable for one or the other, or is it more based on personality, or ? Thanks.
Hey, thanks @Sierra for that venture into foreign territory! FWIW here’s the same (almost) with the current fitting of my four-year-old V90 HAs. This fitting was done in October when I got a custom mold in the left ear, leaving the right with the original open dome. Strangely(?), when I load the fitting from the HAs, the Instruments::Acoustic Parameters page still shows open domes in both ears. If I change it there to the cShell I have in the left, it wants to do a recalculation and another Feedback & Real Ear test. Since this is just a record of my audi’s fitting as it comes from the HAs in case I need to restore from it in future, I haven’t saved that. Changing to custom mold and doing the recalc changes the left ear curves some, but not above 4K.
Mine has Gain Level of 90% (for the gradual adaptation feature), which it’s been forever. I asked my current audi about that and he said he doesn’t use that to change more-or-less overall gain – he ignores it – and does something else instead. (I’ve had several audis due to moving from place to place.)
Not sure why we have different line schemes – I have no dashed lines. But my lines are as follows, starting from the bottom and all at 8k, right ear:
dark red: Gain (80 dB speech)
dark red: Gain (65 dB speech)
dark red: Gain (50 dB speech)
magenta: Feedback threshold
light red: Target gain (80 dB speech)
light red: Target gain (65 dB speech)
light red: Target gain (50 dB speech)
grey: Gain limit
Yes, it defaults to compression (for my audiogram, anyway) but I don’t have SoundRecover turned on. I notice that my diagrams don’t show compression on the right as do yours. I don’t know the function of “Prescribed compression” for this diagram (the alternatives are Linear and Semi linear).
You might be using a somewhat out-of-date audiogram for me. I updated it here within the past few days with my Aug. 2019 one.
Meanwhile, the Post Office says my Noahlink Wireless should be delivered in the next hour or so, and then a bit after that I’m off to Costco to trial (for up to six months) a pair of KS9s. When I get home with those I should be able to see these diagrams for those. I’m curious to see whether the HIS will want to fit with my left-ear custom dome – I assume it’s plug compatible, but I’m not positive. Or maybe without first, and then with.
What power of a receiver are you using? The gain limits seem low. I believe the software picked Medium and that is what my graphs are based on.
I believe the Compression box at the bottom refers to gain compression, not frequency compression. If you change it to linear it should just scrunch the soft, normal, and loud lines together.
For the audiogram, I just used the one that pops up when I click on your avatar.
It appears your gains are being significantly attenuated to avoid feedback, even in the left ear.
My receivers are S/Standard. The alternatives are P/Power and SP/SuperPowerplus.
I updated the audiogram that pops up since you first used one, in case you saved that one. I’ll be getting a new one today.
There should be a M or Medium between the S and the P power receivers. I think the S receiver may be a little underpowered for your loss.
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Learned today at Costco that receiver designations changed after my V90s. For the V90s S is 46/114 (gain/MPO) then P and SP; now M90s have S 46/11, M 50/114, then P and UP. I’m not sure about KS9s; I mistakenly thought I could come home with them today, but they won’t be dispensed until two weeks from today after I paid for them today. Today I had an exam – new audiogram posted in my profile – and a quick fitting so I could try them for five minutes, but the nitty-gritty fitting including REM will be in two weeks. She didn’t think I need the custom mold I have. “No feedback walking around the store, right?” “Right.”
I updated the audiogram, but not really much of a change. Here is what I see with DSL v5. The graph is showing feedback potential starting at 6 kHz. With the Adaptive Phonak it seems to be worse for feedback. This is with power domes in both ears. One thing you have to watch with fitting is that I see a Feedback and Real Ear test tab. Can’t get into it because it needs the aids connected, but if it works like the Rexton Connexx it will cut back gain based on feedback it measures. So when the fitter says “No feedback walking around the store, right?”, it may be that the computer has already cut back gain to avoid feedback. So, no, you don’t get feedback, but you also do not get the prescribed gain.
Thanks, I’ll check out the Feedback and Real Ear issue when I go back. I suspect you’re right. What’s the solution? Skip the test, and then guesstimate what feedback suppression is needed – e.g., closed domes, custom molds?
I tried the different options and the power domes seem to give the best feedback protection in Target. In the Connexx software custom molds with 2.5 mm vents seem to improve things. Not familiar with this software so don’t know if there are any other options…
Thanks for taking the time to lay out some guidelines that integrate science, art, economics & ethics in practice. While I have no hearing loss provider training, some of these elements are present in being a good practitioner of any field. Dr. C’s instrument looks like a great organizer for a provider to make sure they have covered the variables. I’m unclear though how I as a beginning HA consumer would utilize the checklist to decide on a good provider, as it would seem that I would only know if they truly step through all that list with my care AFTER the fact. You & others on this great site stress that REM is non-negotiable & that one element is easy enough to ask up front (which I did when I first connected with COSTCO staff). I’m trying to imagine taking a copy of the multi-page checklist with me & asking them at first meeting - will you do all these steps with me? How would you suggest a consumer might use the checksheet to screen potential providers at the front end of the provider selection? Thanks in advance.