Pros: Size, functionality, and sound quality
Cons: DAC playback sounds a bit better than standalone playback
Fiio has been around for quite some time, starting with a low cost, entry level amp, the E3. It became a hot seller, especially with the limited digital audio player (DAP) choices available at the time, and followed-up by the vastly superior E5. The next several years marked significant growth for Fiio, which has since released many amp and DAC/amps, and finally their first DAPs, the X3. Recently Fiio released a higher-end DAP, the X5.
The X3 is a high-end full-feature player done right, with the ability to play high-res files from internal memory or as an asynchronous DAC. Sound quality is a good step up from phones and lower-end players and the ability to play high-resolution files up to 24 bit, 192 KHz allows users to enjoy higher quality tracks. The feature set is full with plenty of playback options and an easy to use interface. I commend Fiio the overall features, function, usability, and real-world practicality of the X3.
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