The behaviour of the output filter is directly dependent on the connected load. The key figure for this is the nominal impedance of the loudspeaker. As there are known to be different types – usually between 4 and 8 ohms – an adjustment to the speaker impedance can be switched on the rear of the device. This individual adjustment linearises the time response of the filter in particular.
Incidentally, this dependency is an inherent feature of every PWM amplifier. As far as we know, however, we are the only manufacturer to address this issue and offer a solution. It may sound quite good on average even without this adjustment. However, on average, quite good is not a goal for us. Correct matching is crucial for truly harmonious music transmission!