mrgigi, with only one source what you need is the Placette RVC (remote volume control) which i use and am told sounds the same as the Placette passive pre. I have tried the BAT50SE in my system and prefer the Placette although in some systems the BAT50SE can have a better balance with added weight and body.
i have compared the Placette RVC to the volume control in the Audio Aero Capitole 192/24 version 1 and preferred the Placette RVC. the volume control in the Capitole added a coloration and obscured detail. again, in some systems this "warmth" may be preferrable. you do need the additional interconnect as Ultrakaz mentions but that has far less effect on the sound than the mediocre volume control that Audio Aero uses. it is important to keep the interconnect from the Placette to the amp as short as possible to reduce/eliminate any impedence problems.
i have compared the Placette RVC to the volume control in the Audio Aero Capitole 192/24 version 1 and preferred the Placette RVC. the volume control in the Capitole added a coloration and obscured detail. again, in some systems this "warmth" may be preferrable. you do need the additional interconnect as Ultrakaz mentions but that has far less effect on the sound than the mediocre volume control that Audio Aero uses. it is important to keep the interconnect from the Placette to the amp as short as possible to reduce/eliminate any impedence problems.