Oczywisty karmić to może passive preamp volume control kanał Zielone tło Stereotyp
Amazon.com: Passive Preamp Volume Controller, High Precision Passive Preamp Volume Controller, Plug and Play Compact and Portable withConnector for Active Speaker Power Amplifier : Musical Instruments
1pc High End Volume Controller Passive Preamp Stereo RCA HiFi Pre-amp Audio DIY | eBay