A DSP-enabled
system and method for increasing intelligibility of audio on amplified telephones by providing
digital audio processing customizable based on characteristics of
hearing loss specific to individual end users are disclosed. The DSP-enabled amplified telephone generally comprises a DSP capable of implementing at least one digital
processing mode for
processing audio input, a
volume control for allowing the user to select a
volume control level, and a controller for
interfacing between the DSP and the
volume control. The DSP is optionally programmable to implement a processing mode selected from multiple processing
modes that the DSP is capable of implementing. The mode is selected based upon the user's
hearing loss characteristics. The DSP may be further customized by being programmed with
frequency response,
compression ratio, and / or knee point according to
hearing loss characteristics of the user. The DSP may implement digital TILL, BILL, and / or
PILL (treble, bass, and programmable increase at low levels, respectively), all of which apply more amplification to softer inputs than to louder inputs, as well as input compression, output compression, and / or
finite impulse response (FIR) filter tone control.