FiiO K5Pro ESS Review

DAC Performance & AMP Performance

Paired directly with my monitors, the DAC side of the K5Pro ESS sounds engaging with plenty of details. It has an articulate, clean signature with hints of warmth in its signature. The low-end is powerful with a good punch and texture. Midbass is controlled. Furthermore, the midrange sound clean, and upper mids show good extension in an energetic way. The linearity is good, the ranges do not fight each other to steal to show, they rather sound coherently balanced. No unwanted dips or peaks struck my ears. Soundstage-wise, the DAC LO provides a medium-sized stage, not wide and not claustrophobic. It also offers adequate depth. The imaging and the positioning of the instruments are good. The DAC delivers a satisfactory job when it comes to technical capability.

The AMP performance of the K5Pro ESS is good for the price. It sounds balanced across the spectrum just like the DAC. It sounds great combined with a capable DAC like the SMSL SU-6. The K5Pro ESS’ amp sounds neutral and natural. There is plenty of power to feed almost anything too. The noise floor is inaudible with cans so you won’t have to worry about that.

DAC & AMP Performance

The K5Pro ESS sounds great with both my IEMs and headphones. It offers plenty of details and a neutral signature with no emphasis on a particular range. It sounds linear and clean. It makes you feel that heaps of clean power are ready at your fingertips. It also plays well with my in-ear monitors thanks to the low gain. The noise floor is low, with no hissing. The background is silent. The unit reflects the mastering as it is, I can’t spot any dips or peaks here, either. The bass is clean and natural with good impact. The kick and the rumble are impressive and adequately tuned. It does not feel overwhelming or lacking. The resolution is quite good as well. 

For an AIO solution, I expected a compromise somewhere. However, I couldn’t find anything that caught my eye. The midrange feels transparent, clean, and articulate. The mids of the K5Pro ESS do not feel dry at all. Vocals are quite good as well, with adequate body and articulacy. The upper midrange sounds as it should, not too energetic and not recessed. Hi-hats and cymbals sound natural and controlled. That’s quite good, considering the price.

The treble shows good energy with plenty of details. The resolution is satisfactory and the freq range feels vivid. The treble offers good extension and it is controlled at the same time so you don’t get piercing highs or peaks. I haven’t experienced any sibilance with my time with the K5Pro ESS. It stays true to the mastering without saturating the reproduction. 

Technical-wise, the unit performs well for the price. The soundstage is not the most spacious but it is adequate and does not feel claustrophobic. The depth is similar. Furthermore, the instrument positioning feels accurate and the imaging is good. The resolution level is satisfactory across the spectrum and the PRaT is good for the price. Overall, technical-wise the unit performs well.

FiiO K5Pro ESS


vs. SMSL SU-6 & SH-6 Stack ($289 USD)

SMSL’s ESS9038Q2M equipped high-performance budget stack did manage to impress us with its complete package, great sound, and brilliant wireless performance. As a stack, they take up nearly as much space as the K5Pro ESS. Sound-wise, the SMSL stack feels more spacious and the stack’s headroom feels larger in comparison. The stack also offers better imaging and overall better technical capability. As for the power, the stack can dish out 1.3W whereas the K5Pro ESS can dish out 1.45W into a 32-ohm load. The stack offers great wireless sound and it is a feature that’s not available on the K5Pro ESS.

vs. Khadas Tone 2 Pro ($249 USD)

Another ESS9038Q2M device here. The biggest difference between the two is the power. The K5Pro ESS can dish out nearly x5 more power and it sounds more dynamic compared to the Tone 2 Pro. The Khadas feels linear and somewhat dry in comparison. The resolution is impressive on both of the devices but if you are an avid fan of the HD6 series like me, you’d want more power. Apart from that, the bass range of the K5Pro ESS has a better impact and authority. For example, tribrid IEMs sound a little too lean with the Khadas Tone 2 Pro. Apart from that, Khadas is quite portable and you can take it with you anywhere you go. Khadas can be powered through the USB port so it is widely compatible with many devices on the go, unlike the K5Pro ESS.

vs. Topping DX3 Pro+ ($199 USD)

The DX3 Pro+’s review is in the works and it will be published in the near future. Just like the K5Pro ESS, it is also an AIO device that features the same DAC of K5Pro ESS. Topping managed to impress me with its fantastic sound quality and wireless capability in a budget package. It can be used as a separate DAC and PRE. Furthermore, it can dish out 1.8W into a 32-ohm load so power-wise, this puts the DX3 Pro+ in front of all the units that I mentioned here. Sound-wise it feels more spacious, slightly more resolving, and articulate compared to the K5Pro ESS. It has a slightly more energetic and vivid presentation. Instead of a 6.3mm HPO, it comes with a 3.5mm HPO. Stay tuned for the review!


The K5Pro ESS boasts high-quality CNC aluminum chassis with a beautiful finish and it surely is a device that is built to last many years to come. FiiO’s track record is very good when it comes to warranty and after-sales support.

The K5Pro ESS sounds great for the price and it could be your all-in-one solution that you can use in many scenarios. It is a very versatile and practical device that comes at a budget-friendly price.

Page 1: FiiO, K5Pro ESS, Packaging & Accessories, Design & Build Quality, Features, Power & Technology

Page 2: DAC Performance & AMP Performance, DAC-AMP Performance, Comparisons, Conclusion

4.5/5 - (227 votes)


Long time Tech Enthusiast, an ambitious petrol-head, Yagiz likes his gadgets and always finds new ways into the tinkerer's world. He tries to improve anything and everything he gets his hands onto. Loves an occasional shine on the rocks.


  • Reply January 26, 2022


    Thanks for the review Yagiz, it clarified a lot of questions in my mind. I guess you had high expectations for the K5 Pro like I did. I guess we’ll have to wait a little longer.

  • Reply February 9, 2022


    Looking forward to the Topping DX3 Pro+ comparison and review!!! Hopefully it has similar praises as it’s only $200 USD but has bluetooth as well. Will wait for a definite review before making a purchase decision between the Fiio and Topping.

  • Reply February 9, 2022


    Hello Nick,

    Planning to finish the review soon. DX3 Pro+ is a well-tuned unit that offers a great price to performance ratio. Stay tuned for the review!

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