A line stage has three duties. First, it switches the various sources. Second, it controls the playback volume. And third, it conditions the signal in such a manner that even long runs of cable between line stage and power amp will not have an influence on the sound. The most important of course being that the preamp has as little as possible – ideally none – influence on the signal's musical integrity.  

 As usual for Brinkmann, we didn't accept any compromises when developing the »Marconi«. The volume control, for instance, is purely electronic andworks in two planes. First, the sensitivity of each of the six inputs (two of them balanced) can be adjusted individually and saved, thus eliminating the obnoxious jumps in volume when switching between sources. Second, the “actual” volume control consists of a motorized potentiometer that can be operated either remotely or with the knob on the front plate. This potentiometer digitally controls ICs which in turn adjust the playback volume passively with discrete resistors in precise steps of 0.5 dB. The utmost immunity against any influences can only be achieved with balanced signal processing. Which means that for a stereo preamp, four complete amplifiers are required since the signal is processed both in phase aswell aswith a 180 degree phase shift.