FiiO Air Amp Review

 

General / Packaging / Build
The Air Amp comes in FiiO's usual grey card box, no frills, model number FT3001A stamped on the back along with the LDAC and XMOS badges. Open it up and you get the amp itself sitting in foam, the 48V/5A power brick with a locking DC connector, a proper IR remote with batteries, mains lead, and quick start guide. Nothing exciting in the box but everything you need is there.

Build-wise this is classic FiiO. Single machined aluminium shell, about 930g, knurled metal knobs with illumination rings, small monochrome display that just shows input, sample rate, and volume rather than a full menu. No fan, doesn't need one. At 207 x 188 x 42mm it's roughly the footprint of a hardback book, so it stacks cleanly under or over other FiiO desktop gear like the K13 R2R or K11 without looking out of place.

The rear panel is where the story is. Full-size binding posts that take banana or bare wire (not spring clips, which a lot of boxes this size cheap out on), a 3.5mm pre-out, RCA subwoofer out, gigabit Ethernet, USB-C, USB-A, TOSLINK, coax, and RCA line in with a HIGH/LOW sensitivity switch. Seven inputs and three outputs on something this size is genuinely impressive. My only gripe is the pre-out being 3.5mm instead of RCA — means an extra cable if you're feeding a separate power amp or actives.

Setup uses the old captive-portal method: the amp broadcasts its own open Wi-Fi hotspot, you join it, punch in your home network SSID, and it's done. Works fine, the signal-strength readout is a nice touch, but it's a step behind the app-driven pairing you get on some competing streamers.

Gears Used for This Review

• Aune S18 Evo DAC

• Aune S17 Pro Amp

• Burson Conductor Stellar

• FiiO M33 R2R

• xDuoo Link3

• FiiO K17 R2R

Since the Air Amp is a self-contained streaming integrated rather than a headphone source, I mainly used it on its own driving a pair of standmount speakers, feeding it digitally via USB, coax, and AirPlay, and cross-referencing tonality against my usual DAC/amp stack above to make sure I wasn't just imagining things.

Foreword
My review is solely based on what I hear via my equipment and I never consider my reviews to be objective in any way rather a subjective approach. Do take into consideration that everyone's ear anatomy is not the same, so the psychoacoustics perception might be different as well, but i believe it will not stray too far.

Sound Impression
No burn-in claims here since this is a Class D power amp, not a transducer — what you're really auditing is whether it stays out of the way. And to my ears, it does. At its rated THD+N under 0.0022% at 1kHz into 8Ω and SNR above 110dB, this thing is essentially transparent with the PEQ and tone controls left flat. No noise, no hiss, dead silent at idle even with sensitive speakers on the binding posts. No thumps or clicks on power on/off either, which is the first thing I check on any Class D box at this price and the Air Amp passes clean.

Tonally it leans neutral with a slight hint of warmth, not clinical or sterile like some cheaper TPA3255 implementations can get when pushed. The PFFB circuit is doing real work here — takes the feedback signal after the output filter instead of before it, so the frequency response doesn't shift depending on what speaker load you throw at it. That's the difference between this and a bargain-bin TPA3255 board, and it shows up as a more composed, load-stable top end regardless of what's connected.

Speaker Pairing

• ELAC FS 208: This pairing was clean and crisp. The Air Amp powered the FS 208 effortlessly, giving it more than sufficient SPL, and both bass and treble stayed composed and controlled even when I pushed the volume. No sign of the amp running out of breath here.

• Tannoy Sixes 603: On the smaller 603 bookshelf pair, bass leans a touch lighter than on the FS 208, but the mids and treble come through sweet and crisp. Power was never a concern — the Air Amp had more than enough headroom for the 603 to sing without strain.

Bass

• Tight and well-controlled, no mid-bass bloom or bleed into the mids at all

• 120W into 4Ω with the stock 48V/5A brick was plenty for standmounts in a normal-sized room — I wasn't left wanting more headroom

• Sub-bass rumble on Daft Punk tracks comes through with real weight, not just a hint of it

• Kick drum on faster material (Slipknot, Metallica's Lux Aeterna) stays articulate, doesn't smear into a single blob even at higher volumes

• No trace of the mushiness that lower-tier Class D implementations sometimes show at the bottom end

Mids

• Vocals sit a few steps in front of me, not too far away like it's coming from a wall

• Faye Wong's vocal texture comes through clean, no added grain or artificial warmth smeared over the top

• Zhao Peng's low baritone has proper chesty weight to it, the internal DAC isn't thinning things out

• Guitar and acoustic instrument timbre is natural rather than hyped or forward

• Midrange density holds up well even at volume, doesn't get congested or shouty

Treble

• Clean extension, no sibilance or glassiness creeping in

• Cymbal decay and hi-hat transients on Hans Zimmer's Why So Serious keep their edge without turning brittle

• The ESS ES9020Q's reconstruction filter options (eight of them, Minimum Phase by default) are more of a completeness thing than something you'll actually hear a difference from — take it with a pinch of salt if anyone tells you otherwise

• Detail retrieval is solid for the price, doesn't feel rolled off or veiled up top

Soundstage / Imaging

• Fairly spacious, more out of head than boxed-in, which matters here since you're driving actual speakers rather than headphones

• Imaging is stable — instrument placement doesn't wander around when the PEQ is engaged, which is a legitimate concern with a 10-band filter this flexible

• Not quite a hall like effect, but there's convincing width and reasonable depth for the price bracket

• YungBlud's live Bludfest recording separates the crowd noise from the stage nicely, no smearing of the two

Features

• PEQ: Ten bands, each fully adjustable from 20Hz to 20kHz, gain range −24.0 to +12.0dB, Q from 0.25 to 8.00, typed values rather than just drag sliders. That's a serious amount of control for fixing a speaker's tonal quirks. One caveat — this is stereo PEQ only, both channels together, no per-channel correction, and there's no measurement-based room correction baked in. You bring your own target curve.

• Streaming: Roon Ready, AirPlay, QPlay, and DLNA from NAS or USB. AirPlay in particular works flawlessly — shows up in the iOS output picker instantly, no dropouts in my testing.

• USB DAC input: XMOS XU316 handles up to 768kHz/32-bit PCM and native DSD512, though on macOS with the class driver you'll only see up to 192kHz/32-bit in Audio MIDI Setup — worth knowing if that spec is part of why you're buying this.

• Digital filters: Eight ESS filter options on the DAC, Minimum Phase by default. Nice to have, not something that'll change your listening experience in any meaningful way.

• Connectivity: Gigabit Ethernet plus dual-band Wi-Fi, Bluetooth 5.2 with LDAC.

• What's missing: No Spotify Connect, TIDAL Connect. Both which are something that i use often with my A/V receiver, it’s convenient, and hopefully these will be added with future firmware update if possible

Comparison
FiiO Air Amp vs Fosi Audio S3
These two are aimed at genuinely different jobs and it shows the moment you look at the back panel. The S3 is a streamer/DAC/preamp with balanced XLR and RCA outputs, no built-in power stage — you still need a separate power amp or active speakers downstream. The Air Amp is the whole system in one box: streamer, DAC, and a full TPA3255 power stage feeding binding posts directly. So this isn't really an apples-to-apples shootout, it's "do you want one box or two."

On streaming breadth the S3 run circle around the Air Amp. Spotify Connect, TIDAL Connect, Google Cast, AirPlay 2, and Roon Ready (pending certification at review time) versus the Air Amp's Roon Ready, AirPlay, QPlay, and DLNA. If you live inside the Spotify or TIDAL app day to day, the S3 hands off playback natively and the Air Amp simply can't — that's a real functional gap, not a nitpick.

On sound character both are neutral-leaning and clean rather than coloured, but they get there through different means. The S3's AK4493SEQ and dual OPA1612 op-amp stage is a genuinely well-regarded combination and its measured numbers — THD+N around 0.00018%, SNR above 120dB — are reference-grade for the price, and that shows up as excellent resolution and a wide, convincing soundstage through its XLR output feeding my Aune S17 Pro. But that's a line-level output. It needs something on the other end. The Air Amp's PFFB-equipped TPA3255 is doing double duty as both DAC output stage and speaker driver, and while it's not chasing the S3's measured ceiling, it doesn't need to — it's solving a different problem, and it solves it cleanly with no noise, no load-dependent frequency wobble, and enough power for a normal room.

I would personally go for the Air Amp if you want a genuinely complete, one-box solution to drive a pair of passive speakers without buying anything else. The S3 makes more sense if you already own or plan to own a separate power amp and want the best possible line-level source feeding it, and you're fine using AirPlay or Google Cast as a Roon workaround in the meantime. For most people asking "what's the easiest way to get streaming into a pair of bookshelf speakers", the Air Amp is the more complete and more sensible pick.

Final Thoughts
The Air Amp is one of those rare all-in-ones that doesn't feel like it's cutting corners to hit its price. The PFFB implementation on the TPA3255 genuinely earns its keep, the PEQ is precise enough to actually fix a speaker rather than just decorate a spec sheet, and having a real USB DAC input, coax, and full-size binding posts on something this size is not something I take for granted. The gaps are real — no Spotify or TIDAL Connect, if your listening habits already run through Roon, AirPlay, a NAS, or USB, this is a genuinely easy box to recommend and to live with day to day. Recommended? Yes

The FiiO Air Amp was sent over by FiiO for the purpose of this review. Big thanks to the team for the support and opportunity as always.

Head over to their store if you are interested in getting a pair:

• FiiO Official Store — Non Affiliated

• FiiO AliExpress Official Store — Non Affiliated