Review on 🎧 FiiO K5 Pro AK4493EQ: Premium Deskstop DAC & Amplifier with Native DSD 512 and High-Resolution Audio Support by Justin Elmore

I've owned several FiiO products over the years including DAPs, headphone amps and IEMs. For the most part, they worked well, but with a few quirks. This one is no exception. First, why do you need this device? This is a combined DAC and headphone amp. Its main purpose is to decode Hi-Res digital audio and provide a very powerful headphone amplifier. If you listen to FLAC or other lossless formats, this is a good choice. On the other hand, listening to MP3 or AAC and other lossy formats is a waste of time. K5 Pro needs a digital stream to use the DAC. It can be a USB, optical or coaxial input. If your music resides on your computer, you will most likely use the USB input. The optical outputs are also recessed into the headphone jacks on Macs - more on that later. Finally, you can use the coaxial (SPDIF) input. All FiiO music players have coaxial outputs and that works well too. I use FiiO X5 Mkiii DAP and coax output. This works very well. The K5's DAC seems superior to the X5's DAC, and the headphone amp has a lot more power than the X5's built-in amp. Coaxial output is limited to 192kHz/24bit files. In itself no problem. However, so far I have not been able to play native mode DSD files stored on the X5 through the coaxial output. They play, but with a lot of white noise. I have no reason to do so yet. The optical input does not work well. Playback has tiny dropouts. Very annoying. I probably won't use it very often and on the Mac it's limited to 96kHz/24bit. This is a Mac hardware limitation. Another old DAC with optical input looks ok though. Asked the seller for help. Not critical, but not very good either. K5 also has analog inputs and outputs. They are only intended for amplification or output to an audio system. The analog inputs do not use a DAC. I don't use them as I listen through headphones 98% of the time. The headphone amp is great. It can deliver 1.5 watts into a 32 ohm load. That's more than enough to power most headphones. I have Neumann 150 ohm headphones. K5 handles them with ease. Output power is extremely important, especially for low-frequency reproduction. The lower the frequency, the greater the excursion of the headphone driver and the more power is required. The difference is noticeable. The specifications state that the K5 Pro can decode native DSD files up to 768K/32bit. I couldn't test it without having DSD files at that resolution. I suspect this can only work with USB input, assuming you have an external source capable of outputting a DSD stream in native mode. I don't have any. In fact, my software is currently converting DSD to PCM. This isn't a problem as I don't have high-resolution DSD files. DSD is overrated in my opinion as most commercial recordings start with PCM and then convert to DSD. This is because you cannot edit or mix DSD. I tested the K5 Pro with various headphones from Neumann, Shure, Grado, Beyer and Sennheiser and was impressed by the amp in every case. Optical interference aside, I can definitely recommend the K5 Pro. Now the question is: can it be bought? I must have gotten one of the last ones from Revane.