Parametric EQ to replicate someones hearing loss?

Bit of an odd one, but I’m hoping someone on here could help with a better understanding of sound / eq / panning audio tracks than I have :slight_smile:

Long story short - After many operation, one of my children (Ted) has hearing loss in both ears, though it effects one much more than the other. He had a desease called Cholesteatoma

Summary

A cholesteatoma is an abnormal collection of skin cells deep inside your ear. They’re rare but, if left untreated, they can damage the delicate structures inside your ear that are essential for hearing and balance. A cholesteatoma can also lead to: an ear infection – causing discharge from the ear

Essentially the disease ate away the inner ear bones and now he has prosthetic bones - though they don’t have much to attach to… anyway, like I said, long story…

I have these hearing test charts:

What I wanted to try was set a parametric EQ in Bitwig to replicate these so my wife, other son and I can hear what Ted can/cant hear. Any thought about this? would I have two audio tracks, hard paned and then a EQ on each track to replicate?

Then I wondered if this could be reverse engineered so I can boost what’s missing for him? He’s due to have a hearing aid fitted soon, but I though it may help him work out what’s missing. maybe.

Thanks for any help!

Cheers
Bruce

I think simulating it would kinda work like you said, on headphones.

I d be careful with going the other way though. You d have 40db boosts which is VERY loud and might actually cause other damage. Consult a specialist before attempting something like that.

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And: sorry for your little one! Hope the hearing aid will help him well.

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What‘s with these two almost opposite line graphs for the right ear though? Or am I just not fully awake yet and need another coffee :thinking:

Thanks @dtr. Makes sense about that being a lot to boost, I’ll check with someone first but obviously run the volume very very low and check my self. It was really only an after thought about reversing it. It was more for my Wife and I, and his brother, to have a little more understanding of what he goes through.

And thank you, he’s been amazing through all of this and takes it in his stride. His mum and I have had more trouble dealing with it all haha. Kids!

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I need more coffee too! To be honest, its the solid line that I know is the one to look at, but can not remember what the dashed line is all about. I’ll have to check.

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just putting this link here to help anyone looking at the graph. I’m still getting my head around it to be honest

I THINK the dashed line is Bone Conductive hearing…

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Just looked it up. THR AC is Air Conduction Threshold and THR BC (the dashed line) is Bone Conduction Threshold.

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I’ve had a go at this in Bitwig, where doing separate EQ for the left and right ear is fine (using the Stereo Split plugin), but the EQ+ device (I also tried Fabfilter ProQ) isn’t the right tool for the job – all the relative adjustments I made all affect each other and it’s impossible to simply draw in a curve like the one represented in the chart:

So, there must be a plugin that enables you to simply draw in a line to match the charts (or at least their relative values). Maybe others can suggest a decent one to try?

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Well I’m not sure if I’ve done this correctly or not… I can’t get a -45db drop from EQ in Bitwig. But anything under -25db is deemed as hearing loss… so I’ve dropped the levels from -25db (so the first point on the Right ear is 250Hz is at -35db on the chart so I’ve put it at -10db. 500Hz at -20 etc…

Hear Like Ted.bwproject (30.8 KB) Bitwig Beta 4.4 file

EDIT: just like @Craig has mentioned (Thank you! :black_heart:), its Q factor I guess is an issue…

I’ve done one for each channel.

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I think Audacity is free and has a freehand mode:

https://manual.audacityteam.org/man/filter_curve_eq.html

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