Loudspeaker systems, which for technical reasons are not suitable for emitting strong bass signals, can use so-called virtual bass systems. Therein, low frequencies are replaced by their harmonics. However, virtual bass cannot always adequately replace real bass, such that tonal discrepancies may result. Methods and systems are disclosed to improve the bass reproduction of virtual bass by mixing the generated harmonics with a reduced original bass component of the input audio signal. The mixing ratio of this blend can be variable and can be determined automatically. For example, the mixing ratio can change when a level threshold is exceeded, when a temperature rises above/drops below a threshold, a calorimetric threshold is exceeded, or at fixed times of day.