Reduce compression on Phonak Target

Hey, do you know how to reduce compression on phonak target?

You can’t…

I wish we could.

It’s pretty simple: you either tell the aid to act in a more linear fashion in the prerequisites or just let it default a gain setting, then go into the advanced gain adjustments and set the higher gain values the same as the G50 while winding up the MPOs to their maximum and turning the feedback manager off.

If you do this in a nominal music program, you’ll also inhibit a significant amount of the noise management and speech enhancement too.

You’ll have a nice linear sound and very loud sounds will be very loud. This will probably give you more feedback, auditory fatigue and may result in more long term damage to your hearing.

The only people who should be asking for a fully linear aid are those with a purely conductive loss. For everyone else it’s an impossible goal, due to recruitment. However there is merit in asking for an aid to be more linear in order to preserve normal loudness growth - apply judiciously.

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Thanks for that great explanation.
Looking back at this thread reminds me of all the really smart people this forum has had thru the years. um bongo is one of them.

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Assuming Target is the Phonak programing software, one way is to select 1/3 gain as the prescribing formula for correction. 1/3 gain has no compression, but it also has less gain. There may be other prescribing formulas like NAL-NL2, NAL-NL1, DSL v5, and proprietory ones to Phonak. If you look at each one you may find each uses a different compression strategy.

There is probably a way to go in channel by channel and manually set gain to change compression. Or there may be an overall adjustment to change the the gain for soft sounds, normal sounds, and loud sounds. That is in effect changing compresson.

On a quick look of the standard formula options, I think DSL v5 would give you the least compression. It may be worth looking into. Here is the simulated gains. the top curve is the gain for soft 50 dB sounds. the middle is the normal sound 65 dB gain, and the bottom curve is the loud 80 dB sounds. If there was no compression there would only be one line. You will see that the soft sounds are nearly the same as normal, so very little extra gain compared to normal. The loud sounds are depressed some in gain and are using some compression. That would potentially avoid making loud sounds too loud.

To my amateur eyes the DSL v5 looks like a good fit for your loss. Maximum gain is under 30 dB so feedback is not likely to be a big issue, but you will probably need smaller vents to help boost the bass.

You can.
I did. Eventually.

Tell me how…I’ve been told my audiologists that you can’t. You can only adjust the kneepoint.

I wish I could remember!! :joy:
Seriously, I have spent many days, many hours, playing with the software, various settings and various combinations in order to get the aids to perform how I like them and sound just how I want them to, giving me what I personally consider natural sounds, sounds that I have been used to all my life. If the aids do any self-adjusting (compression) for me, believe me, I can hear it and I hate it!

This is a screenshot of the left ear MPO/Gains and if you look at the bottom, the CR shows 1 all the way. It’s my understanding that a Compression Ratio of 1 is no compression, or at least that’s what I was told. If there IS still any compression, it’s so minimal it doesn’t affect me.

LeftEar

On top of that, I also disable all the other automatic shite - SoundRecover, Noise/Wind Blocks etc. I’m used to hearing the natural sounds of the world just as our hearing counterparts hear it all and that, in my opinion, is how it should be.

ETTO though. (Each To Their Own)

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This sounds/looks very much like um-bongo’s description.

From his explanation I get the idea that hearing aid algorithms are based from G50. All the formulas go from there.

If that is true it sure helps me understand better.

I can’t argue with anything you’ve said on a technical level, that is beyond me. However anecdotally, in my specific experience the day i turned off compression on my HAs (about 2 years ago) was the day i started to understand speech better, I am now able to follow conversations in a way I have never been able to in my life (I was born deaf), so now with the assistance of linear aids my hearing is the best it’s ever been. The effect of switching to no compression was pretty much instant, my brain didn’t seem to need to adjust to the more natural sound, but I suppose that makes sense, as it is compression that needs to be learnt is it?

What you say about loud sounds is very true in my case, sounds can be very loud, I have various ways of coping with this, I can reduce the volume, I have modes with the aggressive noise reduction I can switch to, I also preempt situations and adjust accordingly, for example if I’m walking on my own down the street I will turn down 10 db or so to reduce traffic sounds. I don’t know if there will be any damage to my hearing, I have not noticed any degradation, it’s a risk I’m willing to take at the moment to be able to actually understand what people are saying. This is just my n=1 experience, and I do have an unusual reverse slope loss which may be a factor, but I do though wonder if the people who design hearing aids have got the tradeoff between intelligibility and safety right.

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Glad that you have found a solution that works,