This is one of those posts where you think, 'Well I could have told you that!'. Yes, probably true, but I like to have proof of things, and I like to quantify things, because I like science. Good job really.
Anyway, wearing masks and maintaining a social distance in COVID 19 times makes it difficult to hear in three ways. One: you cannot see the person's lips. Even if you think you can't lipread, you very likely are taking cues from expressions and from lip shapes, even if you don't realise.
Two: speech intensity/volume dissipates rapidly over distance. So because the person is a few feet further away, their voice is a fraction of the original volume. People sometimes tend to compensate for this, so they will speak a little louder if you're further away, but they are not very good at getting it right, and the words can get distorted and shouty if they are not careful.
Three: the mask absorbs speech sound, or in the case of hard visors it reflects sound. Particularly high frequency sounds which are more prone to bouncing off hard surfaces. This means that low frequencies dominate more than they should, and speech is dull/muffled sounding.
If all of this is in addition to that hearing loss you have been putting off having tested, you will rapidly start to struggle.
The graph above shows the actual difference that a certain type of mask and a 3 foot distance has on the physical sound characteristics of speech. On the left the green line shows volume of speech at a normal 3 foot speaker distance, averaging about 55dB. The frequency (pitch) runs left to right, so at the left end of that green wavy line is low pitch speech and the right end is the highest pitch speech sounds - such as S and Th.
The graph on the right of the page shows an additional 3 feet of 'social distancing' and an N95 mask. This gives us the pale orange wavy line, and you can see that it is way under the green line, especially on the right end. Speech is reduced by around 10dB on average - this might not sound a lot but it's half the intensity - and the greatest losses of 15dB are in the high frequency end where our clarity-giving fricative speech sounds reside, and where the adult population is already struggling.
This research was produced by Starkey, who are using it to back up their 'mask mode' feature on their in-the-ear custom rechargeable aid. This is a great aid, and it has onboard artificial intelligence which sharpens up the speech when you're struggling - all you have to do is tap the hearing aid twice.
However, while I do sell and recommend the Starkey aid for those who want a rechargeable, custom-made device with nothing hanging behind the ear, I can also add a program to your existing hearing aids for you to use when you are struggling. A program can be accessed easily by your phone app or by pressing a button, and we can set it so it increases the volume by around 10dB and adds extra oomph in the high pitch areas which are dampened by the mask.
As always, get in touch if you are having difficulty - advice is always free and friendly for all.
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