Niles Audio SVC4 4 channel, 4 multi zone high power stereo speaker control selector switch with volume controls. Tested and works great, you can connect 4 pairs of speakers which makes it 8 speakers running at the same time, you can also use 2 sources to connect to it. It has individual volume control knobs for each channel so you can control the volume for each pair speakers! The price is $50 firm, not negotiable.