Car radio receiver with audio frequency response adjustment

摘要

The audio frequency response adjustment device comprises a low frequency, or bass, and a loudness function to influence the frequency spectrum of an audio signal to be reproduced. A bandpass arrangement is provided for realising each of the bass and the loudness functions respectively. The first bandpass circuit is for realising the loudness function is of a wide band pass type and is centred at a first frequency. The change of gain of the first bandpass circuit is independent of the reproduction volume set by the user. The second bandpass circuit is for realising the bass function, and is a narrow bandpass type of filter, centred at a second frequency. The second bandpass gain is preset.