Kitz Forum

Chat => Tech Chat => Topic started by: renluop on June 15, 2018, 11:33:15 AM

Title: I have new cloth for my ears!
Post by: renluop on June 15, 2018, 11:33:15 AM
More seriously rather, I've had my NHS hearing aids updated. Instead of Oticons with thick tubes and earmoulds, it's Siemens with thin tubes and  in the ear. Best of all there's volume control!

Things seem to be improved since audiology has been outsourced from the hospital trust to local suppliers. The one I used was more informative and proactive.

Getting round to the technical, the volume has three settings, the steps being 2 dB. I remarked, that seemed quite a lot, but was told that an increase of 6 dB, (I hope I've got this right) was perceived as half that.

Strange!
Title: Re: I have new cloth for my ears!
Post by: roseway on June 15, 2018, 11:45:43 AM
In the days when I took an interest in audio, 3 dB was generally considered to be the minimum discernible volume change. 3 dB is a ratio of 2, so +3 dB is a doubling of power, and -3 dB is a halving of power.
Title: Re: I have new cloth for my ears!
Post by: 4candles on June 15, 2018, 06:53:00 PM
Exactly so roseway.
In my GPO/PO/BT days, trunk, junction and private circuits were usually lined up to be 3dB end to end loss at 800Hz
Title: Re: I have new cloth for my ears!
Post by: renluop on June 15, 2018, 08:17:36 PM
2 dB or 3 per step, even if halved in perception does seem to make some difference to me. The matter of perception's modifying the effect confuses me. Explanation, please?