I’m new to DIY hearing aid programming, and my first experience at it has been dramatic. I have moderate high frequency hearing loss, and the quality of sound I am getting now is far better than what I’ve had for the last 4 years --since I stared wearing HAs on a regular basis. I used a different (unique?) fitting protocol, and I’d like to share it with others here.
My HA software (Starkey Inspire) has a Fine Tuning section where you can specify the output volume for a dozen diferent frequency bands (200Hz to 8000 Hz) for any of 3 input volume levels (soft, moderate, and loud). The control looks just like a traditional EQ device with sliders you can move up and down. I cleared out all the existing settings (noise correction, automatic learning, etc) and took each slider down to zero for all input levels. I set the compression to 1:1. In a sound editing program (Sony Sound Forge Pro), I created a .WAV file with a sequence of tones (each 3 seconds long) that corresponded to the frequency bands on the EQ control. Then, with my hearing aids connected to the programmer and wearing a good quality set of headphones (Bose Noise Cancelling), I played the tones. From hearing-test software I had used previously (freehearingtestsoftware.com), I found that 200Hz, for me, had the least loss of all the frequency bands, so I used that as my baseline and set the playback volume of my headphones to a moderate level. For each subsequent tone (going from low to high), I would adjust the slider so that it had the same perceived volume as the previous tone. After I was done, I set the compression to maximum for all frequencies and input levels (3:1) and set the attack/release speeds to the maximum allowed.
When I finished, my hearing aids sounded FAR better. I watched a one hour TV drama with a standard loudspeaker and didn’t miss a single word. Before, I would need to wear headphones and then I would still miss a lot of words (and sometimes could never understand them even on repeated playback). The sound quality of my 2006 Volvo’s stereo has been “degrading” and I was just about to buy a new unit to replace it with. Now, with my HAs adjusted, it sounds beautiful. The bass and treble controls sound best at or near the center positions most of the time.
For some reason (probably due to the traditional, convoluted fitting scheme), both audiologists had way over amplified the mid range frequencies and under amplified the high end frequencies. I had been setting the bass and treble of my car stereo all the way up and even bought a sub-woofer to try to get a more balanced, less distorted sound. Now I see that I was trying to compensate for an over-amplified midrange. For non-music sounds (just walking around in life) the volume of everything is much lower than before (with the over-amplified mid-range cut back and the compression set to maximum). The world is quieter but the detail (high frequency information) is still there. The whole thing feels “lighter” and is just much more pleasant and closer to how I remember normal hearing.
I still have more tweaking to do (setting the EQ for soft, moderate, and loud input levels separately and experimenting with different compression strategies), but I had to share this with everyone here. My situation cannot be that unique.