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The FiiO A3 is one of the best-selling portable headphone amplifiers of all time. It wouldn't be wrong to say that it even created the smartphone amp category. But after years on the market, is the FiiO A3 still worth the money? We'll share the answer in this detailed FiiO A3 review.
FiiO is a Guangzhou, China based manufacturer of portable amplifiers and digital-to-analog converters (DACs). The company was founded in 2007 and has set itself apart as one of the few Chinese audio brands to find mainstream popularity in the west, even among discerning audiophiles. It won't be wrong to say that FiiO practically created the portable amp/DAC category from scratch and remains, by some margin, the largest player in this segment.
The A3 is FiiO's mid-range portable amplifier offering. Aimed largely at smartphone and portable audio player users, it boasts a substantial 1400mAh battery in a package barely the size of a large wallet.
In this FiiO A3 review, I'll do a deep dive into the build quality, design, and audio performance of this portable amplifier. You'll learn whether the A3 delivers on its promise of improved audio quality, and how it stacks up against the competition.
Note: The FiiO A3 is a portable amplifier, not a DAC. It only amplifies the signal; it doesn't clean it up like a DAC would. The amplified signal sounds much better, especially on headphones, but if you're looking for sharper, clearer sound, go with a DAC instead of a portable amp. See our recommendations for the best budget DACs here.Quick summary:
- All-around performer that works well with most headphones
- Solid amplification without distortion on most headphones
- Promising battery life (nearly 16 hours of playtime)
FiiO A3 Review: At a Glance
If you're in a hurry, here's a quick summary of our FiiO A3 review. See the good, the bad, and our recommendation at a glance. You'll also see the results of a short poll of our readers where we asked them if they would recommend the FiiO A3:
For a more detailed review, read on.
FiiO A3 Review: Build Quality & Design: 4/5
Overall design: The A3 is meant to be used alongside a smartphone. Consequently, it has roughly the same dimensions as a smartphone, such that you can tie it to the back of your phone for easier portability.
The build quality is solid with a brushed aluminum alloy case and a robust rotary knob. The ports are snug and the switches have a nice tactile feel to them.
If I have any complaints, its about the shape of the unit. The top and bottom of the FiiO A3 are both slightly rounded. This makes it difficult to easily stack them on top of the phone. If you have your phone sitting on top of the A3, it will keep swaying from side-to-side.
Not a dealbreaker, but an annoyance nonetheless.
Let's dive deeper into the build quality and design in this FiiO A3 review.
Portability: The FiiO A3 is roughly the size of a wallet. It's around 3.5″ long and 2.2″ wide. It looks like an early smartphone or a chunky early 2000s era Nokia smartphone. The weight is under 100gm (3.25 oz). To give you a comparison, the iPhone 11 is nearly 6″ long, 2.98″ wide, and weighs around 194 grams (6.84 oz). Which is to say, the FiiO A3 is roughly half the size and weight of an iPhone 11.
Build quality: The FiiO A3's build quality is fantastic. The aluminum casing is tough but lightweight. The brushed sheen looks great. And all the buttons, knobs, and ports are snug and tight. I have to make a special mention of the volume control knob in the center of the device. You'll use this knob a lot; fortunately, it's well built and has enough resistance that you won't accidentally turn the volume up/down.
Controls: The FiiO A3 is veritably minimalist in its controls selection. There's just one large knob and two toggle switches on either side of it. The left switch controls gain on/off, the right one controls bass boost. It's easy to figure out how to use the A3 given this lack of controls. I can also happily say that the switches as well as the main volume control knob are made from high quality materials and feel good to use.
The FiiO A3 checks all the boxes in terms of build quality and design. All the controls are well-crafted, and the device itself feels rock solid.
Where it does miss out on is portability. It's roughly half the size of a smartphone. This might not seem like much, but when you have to lug around 1.5 smartphones all day, it can get tiring very quickly. Together, an iPhone 11 + FiiO A3 combo would weigh nearly 300g – not unnoticeable by any means.
I also don't like the thickness of the FiiO A3. It's roughly half an inch thick – nearly twice as much as the iPhone 11. While this might have been okay half a decade ago, I feel the A3 is a little too thick for the current crop of smartphones.
Sound Quality & Performance: 4/5
Overview: Good design and build quality are important, but the reason you buy any audio gear is the performance.
Since the purpose of the A3 – or any portable amp – is to boost the signal, I'm not evaluating it on the metrics I use to judge DACs, i.e. clarity and accuracy.
My testing rig is as follows:
- Phones: iPhone 11 and OnePlus 7
- Headphones: Sennheiser HD 280 Pro, Audio Technica ATH-M50x, Beats EP, Bose QuietComfort 25, and an assortment of cheap earphones (see some of our picks here)
I also used a range of tracks to test out the A3, such as:
- “Beat It” by Michael Jackson
- “Echoes” by Pink Floyd
- “Contact” by Daft Punk
- “Windowlicker” by Aphex Twin
- “Make It Nasty” by Tyga
Here are my results based on these tests:
I/O Options: The FiiO A3 has three ports at the back of the unit: a) An AUX line-in port, b) a Micro-USB charging port, and c) a 3.5mm headphone out port – in that order. Plug the phone output into the AUX port and use the headphone out to listen to the finished track.
I don't have any complaints about the quality of the ports, but I do wish it could have used a USB-C cable instead of Micro-USB.
Battery Life: The FiiO A3 boasts a 1400mAh battery. For most buyers, this is honestly the biggest reason to buy this device. And it doesn't disappoint – you get almost the advertised 16 hours.
Charging takes about 4 hours, though you can get 6-8 hours of playtime in half an hour of juicing.
A small negative is that the FiiO A3 uses a blue LED to indicate when the amp is charging AND when it's switched on. Though the LED flashes during charging, simply using different color LEDs would have worked better.
Features: The A3 is about as no-frills as they come – except for two features: a high/low gain toggle, and a bass boost function.
The high/low gain toggle lets you switch the amount of power delivered to the audio source. The high gain function works best when dealing with high impedance headphones (anything north of 75 Ohms). I mostly like to keep this switched off since it adds too much volume to the mix. For majority of users, the low gain setting will work perfectly.
You also get a ‘bass boost' toggle. As you can imagine, switching this on boosts bass frequencies. On bass-heavy headphones, this ends up creating a lot of distortion. However, on more neutral headphones, like the ATH-M50x, it makes the soundstage wider and brings the sound together. Recommended if you use more neutral headphones.
Power: The A3 uses the OPA1642 preamp and the AD8397 amp – both proven to work well with low impedance headphones. Officially, the FiiO A3 is rated to work with headphones between 16 and 150 Ohms. Few of you reading this would have headphones rated above this (the Sennheiser HD800 have 300 Ohm impedance but also cost $1,500+).
In actual use, the A3 performs best with mid-range impedance headphones such as the AKG K712.
In terms of power delivery, you get about 15dB of extra volume when everything is maxed out, capping up to 105dB. This is obviously way too loud for headphones and I never advise bringing it all the way up.
Sound quality: The purpose of a headphone amplifier is to, well, amplify an audio signal. The better an amplifier is, the more it will increase the strength of the signal while keeping distortion to a minimum.
The A3 does well on this count – distortion is minimal and the sound coming out of the device is noticeably louder and more energetic. It also doesn't distort the original sound stage of the headphones – when you switch from a neutral pair like the ATH-M50x to a bass-heavy pair like the Beats Solo, you can instantly feel the difference.
Sound quality (cont.): You can say that the output from the A3 is largely neutral (as long as long bass boost and high gain are switched off). There is clear separation of mids and highs. The lows are punchy without distortion, though at lower volumes, it tends to crowd too much.
If after reading this FiiO A3 review, you decide to buy it, you'll see best results with mid-impedance headphones and with both high gain and bass boost switched off.
The FiiO A3 does its job – amplifying the sound signal and increasing its energy and vibrance – perfectly well. It does not add any color to the sound and lets the original source material shine through. It also works well enough with most headphones. The battery life is rock solid, and the limited features make it dead easy to use for anyone.
On the whole, this amp scores an impressive 4/5 stars in the performance section of this FiiO A3 review.
FiiO A3 Review: Overall Score: 4
Good design, good performance, and solid battery life.
Throw in a value for money pricing and you have the perfect first amplifier for a budding audiophile.
If you want more from your standard smartphone audio and want an introduction to the world of high-end audio, the FiiO A3 is one of our most recommended options. It is competent without being flashy, robust without being expensive. You'll get markedly better audio and you won't even have to break the bank to get it.
To round it up, here's where we think the FiiO A3 shines – and where it falls behind.
What's good: The FiiO A3 is a great entry-level headphone amplifier that will substantially improve your listening experience. Here's what you'll love about it:
- Tough build quality
- Quality components – everything from the volume gain knob to toggle switches feel well-made
- The battery life is just-as-advertised – nearly 16 hours of playtime
- Pocket-sized dimensions – perfect for using with your smartphone
- Neutral amplification with minimal distortion
- Adds substantial volume and energy to any track
What's not good: Although it does a lot of things right, the FiiO A3 also misses a few tricks:
- Round-ish top/bottom make it unstable when kept on the desk
- At nearly 0.5″, it is thicker than most smartphones and feels clumsy in the pocket
- A clearer charging/playing LED indicator would have been welcome
- The high-gain function adds too much volume on most headphones – not recommended
- Bass boost feature can distort the bass on bass-heavy headphones
- Since it's a wired unit, you can't use it with wireless headphones – but you probably knew that already
Who it is for: Any music lover looking to improve their listening experience.
The FiiO A3 is perfect if you:
- Want a portable amplifier that works well with wired headphones
- Have decent mid-range headphones to get the most out of your audio
- Are okay carrying around an accessory that's nearly half the weight of your phone
- Our top rated headphones to pair your FiiO A3 with
- Our favorite budget DACs to get even more out of your listening experience