Douk Audio U3 Headphone Amps, Mini Hi-Fi Amplifier for Home Desktop PC 6.35mm 3.5mm Headsets, Class A, RCA Input, DC 5V

The Douk Audio U3 headphone amplifier is a small, affordable unit, which is highly effective. The amp can power a variety of headphones, from 18 to 600 Ohms. It's straightforward to set up and use, as it only requires the input of a low-impedance line level source. As with any amp, the quality of the sound increases with the quality of the source. Some users remarked that the addition of a linear supply wall-wort helped, as it added warmth and detail to the sound. The unit doesn't make any unpleasant noises during operation and takes a few seconds to power up, during which the volume rises gradually. This feature allows the amp to warm up, giving a better sound quality. Some commentators noted that it was difficult to judge the product's aesthetic quality, as this is a matter of personal preference. However, the quality of the sound could not be disputed. Users who upgraded from similar quality amps that were more expensive still found the sound quality to be excellent. In contrast, others noted that the sound quality was lacking, but this may be due to personal preference, as they compared the amp to higher-priced equivalents. However, the majority of users found that the amp performed well for them and enhanced their listening experience.