PreSonus HP4 4-Channel Headphone Amp

These headphone amps are not just loud enough for session and stage use, they’re loud enough to explode the oysters in a Po’ Boy sandwich. Yet the sound is clear and clean, with a wide dynamic range. At last, everybody will be able to hear—assuming they are capable of hearing. Be careful with that level control!

• 4 screaming-loud (150 mW per channel) stereo 1/4" headphone outputs (front panel)
• 2 balanced 1/4" line outputs (monitor outputs)
• 2 balanced 1/4" line inputs
• Meters, Controls, and Features
• Headphone level control for each channel
• Mono summing switch for each channel
• Monitor level control
• Monitor mute switch
• Daisy-chain multiple units via monitor outputs

• Compact 1/3U rack-mount chassis
• Sealed, detented, metal rotary controls
• External 16 VAC power supply

• Connector Type: 1/4" TRS, balanced
• THD+N: 0.0025%, 1 kHz, unity gain 
• Max Input Level: +18 dBu, <0.5% THD+N, unity gain 
• Input Impedance: 10 kohm
• Frequency Response: 20 Hz - 20 kHz, +/-0.5dB

• Connector Type: 1/4" TRS, asymmetrical, impedance-balanced
• THD+N: 0.0025%, 1 kHz, unity gain 
• Max Output Level: +18 dBu, <0.5% THD+N
• Output Impedance: 51ohm
• Frequency Response: 20 Hz - 20 kHz, +/-0.5dB 

• Connector Type: 1/4" TRS, stereo
• Max Output Power: 130 mW/Ch., <0.5% THD+N, 60ohm load
• Frequency Response: 20 Hz - 20 kHz, +/-0.5 dB, 60ohm load
• Headphone Impedance Working Range: 32ohm - 600ohm

• External Adapter Type: +12 VDC, 1000 mA, center pin positive

• Dimensions: 1/3U rack-mount (with standard rack tray, not included)
• Height: 1.75" (44.45 mm)
• Depth: 5.5" (139.7 mm)
• Width: 5.5" (139.7 mm)
• Weight: 5 lbs. (2.27 kg)