2 x Behringer AMP800 4ch Headphone Amps
 
Can run 8 sets of headphones off one unit
 
Both units have some issues however can still be useful for a home studio setup
 
One unit works well except Channel 2 only the left side works, all 3 other channels work fine and the power input connector is loose
 
The other unit has a small hum on channels 1-3 and channel 4 is quite noisy
 
Both come with power supplies