Amazon.com: Neewer Super Compact 4-Channel Stereo Headphone Amplifier with DC 12V Power Adapter for Sound Reinforcement, Studio, Stage, Choir, Personal Recording, Features Ultra Low Noise (Original Version) : Musical Instruments
Buy Samson Audio QH4 4-Channel Stereo Headphone Amp Distribution Amplifier Black Online | Kogan.com. .
Amazon.com: Fifine Headphone Amplifier 4 Channels Metal Stereo Audio Amplifier,Mini Earphone Splitter with Power Adapter-4x Quarter Inch Balanced TRS Headphones Output and TRS Audio Input for Sound Mixer-N6 : Electronics
Behringer HA400 4 Channel Stereo Headphone Amplifier for Best Price | Music Stores