Enhanced Compatibility: U3 adopts simple RCA input and 6.35mm headphone output, while U3 PRO is upgraded with 3.5mm AUX/stereo RCA input and 3.5mm/6.35mm headphone jack output. The U3 PRO is compatible with more audio sources, including MP3 players, iPods, smartphones, tablets, computers, and CD players etc., and more headphone models as well. Built-in Voltage Boost Circuit: U3 PRO adopting innovative circuit design with built-in voltage boost circuit, the amplifier circuit can work at a higher voltage of ±14V even only powered by DC 5V, and the background noise index is excellent. With wide frequency response extension, excellent transient response, excellent purity and transparency, and good dynamic range.
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Experience music like never before with thePortable HiFi Stereo Audio Headphone Amplifier. Introducing the Portable HiFi Stereo Audio Headphone Amplifier, the ultimate solution for enhancing your audio experience on the go.
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Multifunctional DAC Preamplifier: The GR40 is a versatile tube DAC preamplifier and headphone amplifier in one. It supports Bluetooth/USB/Optical/Coaxial inputs and active speakers/3.5mm headphone output, with a priority mode for headphones.
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In excellent working condition
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Monoprice 4-Channel Headphone Amplifier – Expand Your Monitoring Power. It accepts line-level audio via stereo RCA inputs or headphone-level input through an optional 1/4" TRS jack. A mono/stereo switch on the back lets you customise your output mode to suit your session.
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Great all-in-one R2R DAC/Amp.
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Hey, got for sale this great Headphone AMP in very good working and visual condition, it plays very loud and clean, don't even have good enough headphones to use it with. I can include it for an extra £10.
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The resolution and restoration power are convincing, and the strong output power presents. UP4 2022 adopts Bluetooth 5.0 version, supports LDAC / LHDC /. The UP4 2022 is equipped with a 2.5 + 3.5 mm dual interface.
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