Interesting… I hadn’t heard of the Nura. So thanks for putting me on to it. Mine just arrived this afternoon.
While I think the premise of otoacoustic emission measurements, possibly leading to more accurate room-level audiology, is intriguing, the jury still seems out. I have to state, that after a number of hours carefully listening to it, it is lacking quite a bit. Either their measured audiology for my hearing is poorly done, or the premise of otoacoustic emission measurements doesn’t work very well after all, or else, what they do with that information to correct the sounds is poorly done. I strongly suspect the latter.
I could tell by listening to extreme dynamic range material that they are using some form of compression. The difference between very soft and very loud was not as great as what I know it to be in the recordings. And that by itself is not particularly damning. It is likely a linear dynamic range compression over the entire loudness range, and not particularly frequency specific.
But they aren’t restoring anywhere near what I am accustomed to hearing with Crescendo. The Nura playback sounds flat and lifeless, compared to an enthrallingly deep and wide soundstage that you could just tumble into with Crescendo.
In general, just about anything you do for hearing assist sounds better than doing nothing. And whenever you listen to something new, it can also sound better, even when it might not be. But I am severely disappointed in Nura. It is very bass heavy, even after turning “immersion” all the way down. And that bass extends well into the lower mid-range to around 200 Hz. The highs are enhanced, above doing nothing, but not nearly enough to recapture the extreme highs that are in there. And I can’t escape the feeling of lifelessness in the Nura playback.
For a good test of dynamic range response, try listening to a recording of Rimsky-Korsakov’s Scheherezade. The very beginning has the first violin playing solo in a very high register and pp levels. Then at the other extreme, the 4th movement contains some jarringly loud trumpets.
If they were doing something as lame as mere equalization, then I shouldn’t be able to hear much of the violin, while the trumpets would have knocked me out of my chair. I know that from experience with a graphic EQ from way back when I didn’t know anything about hearing.
But the Nura playback did allow me to catch some of the pianisimo high register of the first violin, yet not all of it. And the trumpets sounded rather tame - perceptibly louder to be sure, but not blaring as they really are. So that argues for linear dynamic range compression, much like car stereo playback systems. And maybe it even has some frequency selective behavior, but certainly not tuned to each critical band of your hearing. Perhaps a half-dozen bands or fewer.
Maybe, in the face of market realities, these devices are not really aimed at those of us with hearing loss. Perhaps for wider audience with more normal hearing, the Nura customized playback sounds good to them. And perhaps, for fear of possible damage liabilities, they are intentionally limiting what it could do for the hearing impaired audience.
It was worth a listen, to see if any progress has been made on the other side of the universe. And perhaps some progress has been made. But it still falls disappointingly short, by a long shot. At least they didn’t turn oboes into muted jazz trumpets, like most hearing aids do.