I’ve been trying out different hearing aids lately, and the Oticon Real is my favorite so far. However, I still have some questions and would like to gather more information on certain aspects.
1. Distortion/Speech Clarity
With the Oticon Real hearing aids, my best speech clarity is around 60 dB. Increasing the volume actually decreases my ability to understand speech (based on freefield measurement: https://imgur.com/a/lMnzJ7c). However, this issue doesn’t occur with the Omnia hearing aids, and with my older LiNX 3D, my speech clarity is even better at 55 dB. The hearing care professional suggests that it’s a limitation of my brain and cannot be solved by using different domes or settings. 1a. What could be causing this?
2. Choosing the domes
I’ve visited four hearing care professionals so far, and they all seemed to randomly choose a set and adjust it through trial and error (“does this feel too big?”). Maybe I’m being overly particular, but I can feel significant differences between 6, 7, and 8 mm domes, even though the differences don’t look that significant to me. One HCP suggested open domes, while another recommended power domes. 2a. Is there a guideline for selecting the appropriate domes and speaker wire length? 2b. Why are there so many different suggestions? 2c. I found Phonak domes to be more comfortable than Oticon domes. Can I use Phonak domes with Oticon hearing aids?
3. Real Ear Measurement
One of the hearing care professionals didn’t perform REM at all. 3a. When should a Real-Ear Measurement (REM) be done in general? 3b. Is it necessary to do a new REM when using different domes with the same hearing aid?
After trying the Real hearing aids, I tested the Omnia hearing aids. The HCP said we didn’t need to do a new REM because she transferred the REM from the Real’s to the Omnia’s. 3c. Is it really possible to transfer REM between different hearing aids?
4. Insertion Gain
My HCP mentioned that the insertion gain is the same across different devices. 4a. Can I directly use my insertion gain settings 1:1 on other devices? 4b. How do hearing aid manufacturers incorporate their hearing philosophy into devices if the insertion gains are identical?
A few years ago, I visited an audiologist at the hospital who fine-tuned my LiNX 3D hearing aids for optimal hearing. The adjustments resulted in the following gains: https://imgur.com/a/cr49BD5. As you can see, there are minimal gains in the lower and higher frequencies (even compared to NAL-NL1 recommendations), but there is a higher increase in the mid frequencies. 4c. What are your thoughts on this? Is this widely used or a well-known technique?
5. Feedback settings
One of my HCPs always sets the digital feedback suppression (DFS) to the maximum level. 5a. Is there a downside to this? If not, why isn’t it set to the maximum level by default?
I would greatly appreciate your insights on these matters. Many thanks in advance!
I’ll try a few.
2) Re: domes. With your loss I think you’d do best with custom molds. They will allow the most gain without generating feedback
3)REM is recommended for anything that changes the acoustics so new hearing aids and any change domes/molds
5) With your high frequency loss I think it would be challenging to get adequate gain without feedback, hence the choice of max feedback suppression. Feedback suppression does introduce some distortion so if you don’t need it, it’s likely better to have setting set lower.
I’ll let others chime in.
@elderflower , what is your subjective experience? Do you feel that your speech comprehension is better with one particular model of HA that you have tried?
You say the Oticon Real is your favorite so far. What do you like about it? What is most important to you? Many users like the “natural” sound of Oticon. As for me, speech comprehension, especially speech-in-speech-noise comprehension, is the most important thing. I would prefer unnatural, robotic sound where I could understand a speaker’s words better, over “natural” sound that might not produce as good speech comprehension. Others might prefer more natural sound at the expense of speech comprehension.
Do the Reals, or the Omnias give you better overall speech comprehension compared to your present HAs? If not, why spend the thousands of dollars to replace them?
Sorry, I’m not very familiar with how the free field measurement process works to measure speech clarity so I can’t really offer any comment on this question. If you can elaborate on what this free field measurement process is, maybe it’ll help me understand it better. Is it just a word recognition test, but instead of listening through the headphones in a quiet booth, it’s played through the speakers at various loudness levels? Word Recognition Score is completely different than Speech Clarity. Word Recognition Score is based on single word hearing in a quiet environment and the ability to recognize what the word is. Speech clarity is the ability to understand a sentence or two or three or more of normal conversational speech in a noisy environment. So when you talk about speech clarity in a free field measurement, it puzzles me about the details on how such a thing would be carried out inside an HCP’s office environment?
2.a. I would think dome selection can simply be common sense. The HCP would look into your ear canal to determine whether your ear canal is a typical size or smaller or bigger, then dispense the appropriately common sized dome base on their assessment of their experience on what size dome is a good fit for what ear canal size. Then go up or down a size based on your feedback after you’ve worn it for a little while.
2.b. Probably due to inexperience or laziness or a combination of both in trying (or not wanting to try) to professionally do a good guesswork for you based of their experience, if they have any/enough experience.
2.c. I think usually the answer is yes as long as they fit snugly the same way. Also, if you use closed domes with vent holes, just be mindful that one with a single vent in one brand would give you a different response versus one with a double vent in another brand. It would be best to match the number of vent opening(s) closely to get a more accurately matched prescribed amplification. For open domes, the vents are fairly big and wide open so it’s not as critical to match them more closely.
3.a. REM should be done in your initial fit. If you change your fittings (like go from open to close domes, or from domes to custom molds), or change receiver size, you should probably do REM again because the physical fittings can alter how the sound is delivered to your ear canals.
3.b Yes, in general. But let’s say if you switch from an Oticon open dome to a Phonak open dome, then maybe not necessary (imho). Or if you switch from an Oticon closed dome with 1 vent hole to a Phonak closed dome with 1 (same size) vent hole, then probably no. But if you go from an open dome to a close dome or a power dome, regardless of same brand or different, then REM should be redone because the openness or closeness of the domes will cause a difference in the leakage of the sound output that reaches your canal.
3.c I’m not an HCP, but in my opinion, your HCP is not correct to transfer the REM result from one hearing aid brand/model to another hearing aid brand/model, because that is based on an assumption that the Real and the Omnia aids deliver the exact same sound output volume at every single frequency, which is highly unlikely, even if possible. REM is done to make up for not just the variances in the physical fittings (domes or molds) of the hearing aids, and the variances in your own ear canals compared to other people’s ear canals, but also as importantly on the variances of how the actual hearing aids perform. If the hearing aid underperforms and does not deliver enough amplification at various frequencies (in combination of the fitting and ear canal variances), REM would catch this deficiency to let the HCP know to boost up the gain to the target (or conversely, if overamplified against target, then to tame down the gain to the target).
Even if you replace your Real hearing aid with another exact same brand/model/tier Real hearing aid, who’s to say that they would deliver the exact same amplification performance? More than likely, they will, but variances in the manufacturing process (if loose tolerances are condoned) may still result in slightly different amplification between one aid and another.
But I would not argue with my HCP if they transfer my REM adjustment from one Real hearing aid to another as long as they’re the exactly same brand/model/tier. But transferring REM adjustment between one brand of hearing aid to another brand? Heck, no. That’s just lazy and a lame excuse.
OK, the insertion gain of 1 dB in one device may be the same as 1 dB insertion gain in another device, regardless of whether they’re same or different brand or model or tier, as long as they’re accurately calibrated somehow to be actually 1 dB.
4.a But to take the gain curve from one brand/model/tier and copy it to the gain curve of another brand/model/tier is a big no no in my opinion. The gain curve is a result of many things, the amplification prescription based on your audiogram, then your fittings, then your REM adjusted amplification, not to mention the processing parameters anywhere from the fitting rationale selected, to the program of choice (like music or speech in noise or outdoors), to technologies like frequency lowering, sudden sound stabilizer, wind handling, feedback management, the amount of noise reduction selected, the personalization for either clarity/sharpness or comfort/softness, etc and etc. Many, if not all, of these things can affect what the gain curve will look like. To just copy the gain curve of one device over to another is just a lazy cop-out to replace doing the proper job of fitting and adjusting to arrive at a proper and effective result.
4.b Exactly. To begin with, most hearing aid mfgs have their own different proprietary fitting rationales, based on many things, like the hearing loss profiles (ski slopes or cookie bites or flat loss or reverse ski slope or reverse cookie bite, etc), and all of these nuances in their fitting rationales will affect the end result of the prescribed gain curve, not to mention all the parameters mentioned above in 4.a. So even laymen like you and I already see through the farce that tells us that all insertion gain curves are identical between devices. I don’t really know where they’re coming from to be telling us that gain curves are identical and can just be copied from one brand/model to the next. If it’s from the exact same brand/model/tier for the same settings as a replacement to a defective hearing aid, then OK. Otherwise, it’s nonsense.
Without know the interaction between you and your HCP that arrived at these curves, nobody can really know what to say about these end results, except that if you’re happy with this end results, then OK, your HCP must have done a good job. But it’s not possible to look at the end results like these and be able to determine what techniques they use. There seems to be a lot of emphasis in the 2 KHz range while your hearing loss is flat. It may not be any set technique used per se. It might just have been trial and error adjustment based on the many sessions they spend with you to arrive at this final result from a differently looking original beginning result.
I can only comment if this question pertains to the Real Feedback Management setting, which is the new Real Optimizer feedback prevention technology. If it’s in regard to other brands/models/feedback management technologies, then my comments here don’t apply. But yes, in general, if you don’t really have any issue with your HCP setting the new Real Optimizer Feedback Management setting to Normal, which is the max level (other than Low or OFF which are the other 2 levels), then it’d be the appropriate thing to do, to set it as Normal. There’s no downside to it, UNLESS you start hearing fluttering sounds on occasions (that is designed to stave off feedback when the potential for feedback to occur is detected), and this fluttering sound happens often enough to annoy you, then it can be changed to Low to minimize the fluttering issue. But in return, the potential for feedback to occur may be higher if you set this to Low or OFF. But if it must be at Low or OFF, then your HCP can activate the older traditional Feedback Analyzer that is still available to supplement the newer Optimizer Feedback Management feature.
I lean towards Oticon because I had bad experiences with Resound’s reliability in the past (my LiNX 3D had to be repaired yearly). Oticon’s Real feels sturdy and gives me more confidence. Also, Oticon’s MFI is more convenient for iPhone users compared to MFA. And I like the quick (un)mute control buttons while streaming.
However, the Omnia has an advantage in speech comprehension, based on both my feelings and the freefield measurement, which makes the decision harder.
I’m sorry! Yes, it’s a word recognition score (it’s called free field speech recognition test in my country). Can a word recognition score be used to compare hearing aids?
One of my HCPs tested my Phonak Lumity hearing aid in a simulated noisy environment using speakers by the way. So it would be possibile in some sense.
Thank you for explaining!
Once gain, thank you for explaining.
This confirms what I thought.
Highly informative, thanks.
I’m also confused because it’s not focused on NAL-1 or NAL-2, yet it provides clear speech results despite its 2 KHz range focus.
As I said in question 1a, I’m encountering distortion. Could this distortion be caused by the feedback manager, as you mentioned in your response? Could you offer more clarity regarding the characteristics of the so-called “fluttering” sound? How can I identify or recognize this particular sound?
Distortion is a very general term that simply implies inaccurate representation/reproduction of something. It can be due to saturation clipping, feedback, fluttering, etc. Even frequency lowering (like with Speech Rescue) can be labelled “distortion” because it is moving sounds from one frequency area to another (lower area), so technically it is an inaccurate rendition of the original sound.
If the distortion you hear is fluttering, then maybe it’s due to the RealSound Optimizer feedback management. The easy way to see if that’s the real cause or not is simply to set the Feedback Management to OFF in the Automatics page of Genie 2 to see if the distortion you hear goes away or not.
In terms of offering more clarity on the fluttering sound, I cannot describe it myself because I’ve never heard it, because I’m still wearing the OPN 1 which doesn’t have the Sound Optimizer feedback prevention technology. But if you do something that normally would cause feedback before (like cupping your hands on your ears, lean your head on a pillow on the side, but now it doesn’t cause feedback anymore, but you notice some kind of rapid sounding anomaly, then that’s the fluttering people are talking about. Maybe somebody who’s reading this and have had first hand experience with hearing this fluttering can chime in here and describe it more clearly for you.
To get some clarity on what the technology is doing (not the same as what the fluttering “sounds” like), below is a screenshot that explains it. As you can see, it’s a time lapse (on the X axis) of somebody saying “What can I have for dinner tonight?”, except the in between the “can I have” part of that phrase, denoted by the vertical rectangular box, a flat hand is placed closed to the ear to “force” feedback to happen.
These are spectrograms, showing the level of spectral energy in colors over that 2 second time lapse. Dark blue is very low energy, blue is low energy, green is medium energy, yellow is high energy, and red is very high spectral energy, the kind that can trigger feedback to happen. The Y axis denotes the frequency range of the speech sentence between 0 to 10 KHz.
The bottom spectrogram is for the OPN, and the dark red part of it when the hand is put over the ear is showing very high enough spectral energy that would cause feedback to occur. The middle spectrogram is that of the OPN S (with the OpenSound Optimizer feedback prevention feature) with the STMs (Spectro-Temporal Modulations, or the “breaks”) inserted 8 times in the light blue color for the duration between 0.4 to 0.8 seconds where the flat hand was over the ear, to “stave off” the energy build up seen in the OPN in order to prevent feedback from happening. These STM breaks seems to be in the 2 to 3 KHz range of frequency. So if you can hear it, it would be some kind of “sound” at around 2.5 KHz, repeated 8 times in less than half a second. What does it sound like exactly, I don’t know. But a rapid 8 times repetition pattern in less than half a second is described as a “flutter” by many folks who can hear it. It’s not always a guarantee that you would hear or notice it, but even if you do, as long as it’s not annoying enough, this short half a second “flutter” would still be preferable to full-on feeback.
That is plausible, especially if the distorted sound is loud enough. I agree that it doesn’t hurt to try to tame it down. You can always turn it back to the original value if you find it not to be the culprit after all.
Do note, however, that if we’re talking about the Real here, there’s no more Transient Noise Management. The Sudden Sound Stabilizer (located in the Fine Tuning section of Genie 2, with 5 values beside the OFF) now replaces the TNM that used to be located in the Automatics section, which is no longer there in Automatics anymore for the Real.
But based on all the feedback I’ve read so far on this forum about the Sudden Sound Stabilizer in the Real, I haven’t heard anybody complain that it causes sound distortion for them.
The Transient Noise Management (TNM) that existed before the Real (for the More and OPN S and OPN) is a lot more crude compared to the Sudden Sound Stabilizer. When I have it set on my OPN 1, the sudden loud sounds (like the pop of a tennis ball when struck with a racket) becomes muted (as intended), but I wouldn’t really call it distorted. And it would only apply to sudden and loud sounds. Normal sounds don’t sound distorted in anyway even if I have TNM set to High.
Yeah, OK, I see that those 2 threads you mentioned your read about were for the More, so TNM (and not the Sudden Sound Stabilizer) would apply in those situations like you said. I was just saying that in the case of the Real (which is in the title of this thread), TNM wouldn’t apply to the Real, because TNM is not available in the Real. However, your point is still valid that sudden sound handling, whether by TNM or by the Sudden Sound Stabilizer, may contribute to distortion.
Not sure if in the first example you gave above, the complain from the OP in that thread was really about sound distortion per se, though. It seems to be more about the processing of the sound which seems to make it harder for the OP to understand speech, thereby the OP prefers to turn it all OFF. The kind of processing features of the sounds that the OP in that thread dislikes are not necessarily bad, however. It’s a matter of personal preferences. Most other people (myself included) would prefer to use all of those features instead of turning them off because they usually help with speech understanding, not hurt speech understanding.
In the second example you gave above, it looks like the poster confirmed that the issue was due to the MoreSound Optimizer Feedback Management and not TNM, because it was able to be solved completely by turning off the feedback control. That “submarine wooshing past” sound as described by the poster there apparently must be that “fluttering” sound described by others created by the STM breaks in the MoreSound Optimizer.
I am with you, @Volusiano. My hearing loss is mostly conductive and not that bad compared to many here. For the most part, I am OK with the digital features of my More 1. I have been using with success the “lecture” program in noisy and crowded places. However, I use a program with considerably less “digital assistance” for situations I regard as “intermediate”: a bit of echo here and there, a few people talking around, soft ambient music in the background, etc.
In these situations, I feel those digital features take a bite out of speech cues, which hinders comprehension.
