The Apart SVC4 is a unique multiple stereo volume control. It gives you the possibility to adjust (or switch off) the volume in 4 different zones. SVC4 can be used with a standard HiFi amplifier.In case you only want to adjust 2 zones, you can use traditional 8 Ohm loudspeakers. If you want to adjust the volume in 3 to 4 zones, you have to use 16 Ohm loudspeakers. You may use 2 loudspeakers per zone.The SVC4 uses internal resistors. In this way you can adjust (or switch off) the volume in one zone, without influencing the volume in the other zones.Built-in in a compact black metal housing, such is very durable due to the step-by-step volumes.