Patent ID: 7239711

Claim:
A hearing aid system for in-situ fitting of hearing aids, said system comprising a hearing aid, said hearing aid having a microphone, a signal processor for processing an output from said microphone, a digital amplifier for amplifying an output from said signal processor, an output transducer for converting into sound an output from said digital amplifier, and a control signal receiver means, a control device, said control device being adapted for communication with said control signal receiver means for selective generation and feeding of a test signal to said output transducer a voltage dividing network adapted to cooperate with said digital amplifier so as to attenuate said test signal as fed to said output transducer, and switch means for optionally switching between a first position and a second position, said switch means acting in said first position to connect said voltage dividing network to attenuate said test signal, and said switch means acting in said second position to bypass said voltage dividing network in order to feed said test signal directly to said output transducer.