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Fiio A5 Portable Headphone Amp Review


Senior Member
Apr 25, 2018
Western New York, USA
Never really tried my A5 with anything other than IEMs and a few portable cans, but today I have been trying a few of my headphones, and this little amp has not struggled one bit. ATH-R70x, LCD-2, Clear, no problems with plenty of power to spare. Will try the 600ohm Beyer T1.2 and the HiFiMan HE-6se and let you all know.


Senior Member
Nov 22, 2018
Please update "Amplifier best case sinad" pictures with the score of the A5 :)


Active Member
Forum Donor
Aug 3, 2018
Hey Amir,

I know this one is long in the tooth already, but I'm wondering if your measurements would benefit from not connecting USB power to your PC in the future. I bought two or three of those cheap inline USB power (V, I, and W) meters, and oddly enough, all three seem to match the output of each other when measuring.

That said, using my PC USB to charge stuff, I see the output go from 5-5.1V, then drop instantly down to 4.8-4.9V and fluctuate once connected to even a mouse. I suppose that's probably within the spec of most devices, but who knows who large that swing could be from other motherboards?

I'm just throwing this out there, because I have an A5, and I literally leave it plugged in all of the time during use, as it's connected to an audio interface from a manufacturer that still doesn't comprehend the 1/8th rule in regards to output impedance. I can crank that little amp beyond 3 o'clock in low gain, on my cheap NuForce/Massdrop EDC3's without a single ounce of hiss, music playing or otherwise. So, I'm wondering if it's the source (PC USB) or the charging power supply at fault for the degradation in measurements when connected to power. Fiio does mention something about their "smart charging" circuit, which could be injecting noise as it monitors.

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