This unit is like new, and was only used for a couple of weeks. Comes in the original box with all accessories, manual/warranty cards. I’ve been trying out a lot of different stuff lately and have upgraded to a more expensive dac/amp. This makes a great all-in-one desktop unit. I ship for free same day by 4pm central with tracking/insurance. More details about the DX3 can be found online. From the manufacturer:

Topping DX3 Pro is a highly advanced desktop multitasker. It is a USB DAC, Bluetooth receiver, headphone amplifier and preamplifier. All enclosed in a stylish anodized aluminum case fitted with USB, coaxial and optical inputs, and RCA and 3.5mm jack outputs.

Headphone amplification stage in DX3 Pro is based on a very good Texas Instruments TPA6120A2 chip. The TPA6120’s current-feedback AB amplifier architecture delivers high bandwidth, extremely low noise, and up to 128dB of dynamic range. Three key features make current-feedback amplifiers outstanding for audio. The first feature is the high slew rate that prevents odd order distortion anomalies. The second feature is current-on-demand at the output that enables the amplifier to respond quickly and linearly when necessary without risk of output distortion. When large amounts of output power are suddenly needed, the amplifier can respond extremely quickly without raising the noise floor of the system and degrading the signal-to-noise ratio. The third feature is the gain-independent frequency response that allows the full bandwidth of the amplifier to be used over a wide range of gain settings. It is capable of delivering up to 700mW per channel (@ 32ohm), making it capable of driving a vast majority of headphones. On top of that, the gain is adjustable: it can be either set to 0dB or 9dB.