Differences between NAL-NL2 and Adaptive Phonak Digital

Hearing Aids
#43

You can re-derive the CR by noting that the input curves are 15dB apart.

At 250Hz the output curves are 15db or 14dB apart so CR is 1.0 or 1.1.

At 4kHz, the NAL2 curves are: 50-65dB = 8dB; 65-80dB = 5dB. 50-80dB (30dB) is compressed to 13dB.

  • 50-65dB = 8dB , CR=1.9
  • 65-80dB = 5dB , CR = 3.0
  • 50-80dB = 13dB, CR = 2.3

This gradual rise of CR with level is useful and natural. In music studio dynamic control they say “soft knee” or “Over Easy®”.

#44

I presume this is DSL v5 (for adults). Correct?

#45

Correct!

And here are some more characters to keep the forum software happy.

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#46

Thank you so much for your post. I will try NAL-NL1 tonight :slight_smile: