I tried the top-rated DAC on Amazon – and it quickly went from good to bad to ugly

I tried the top-rated DAC on Amazon – and it quickly went from good to bad to ugly
(Image credit: Future)

Newsflash: Amazon is a difficult entity to ignore. The in-your-face retailer stocks an unrivalled number of hi-fi, AV and consumer electronics products; it is fiercely competitive on pricing, often undercutting competing retailers; and it offers the convenience and entertainment package few others can match. So it’s imperative that we at What Hi-Fi? keep an eye on Amazon’s catalogue for potential products to review, or good deals to highlight to our readers.

What is almost impossible to ignore during a casual perusal is Amazon’s highest-rated products – which I’m sure are often their best-selling too – such is their priority in search results alongside sponsored listings and deals. So when I typed ‘DAC’ into the retailer’s search bar, I was pleased to see a What Hi-Fi? Award winner, the iFi Zen DAC V2, up near the top. Just above it, though, was a stranger to me: the Fosi Audio Q4, with a 4.4- star customer rating from more than 2000 reviews and a very appealing price tag of £70 / $80, a figure that has fluctuated regularly – to as low as £55 / $67 – since I first spotted it in late June. As with many of the thousands of electronics retailers selling on Amazon, many of them Chinese of course, I hadn’t heard of Fosi Audio before. Was I missing out on a gem that so many had raved about? Was this little Q4 going to be The Next EarFun Air, a pair of budget true wireless earbuds we discovered through Amazon that went on to win a five-star review for their excellent value? I wanted to become acquainted with Fosi, so into my Amazon basket the Q4 went.

Fosi Q4

The Fosi comes with three cables so you can get started right away (Image credit: Future)

Getting your money’s worth...

Arriving in typically rapid Amazon fashion (had I even finished checking out yet?), the Q4 made the kind of positive first impression that a buffet does – you don’t know what you’re sampling quite yet, but you have an inkling that you are going to be getting your money’s worth. That’s because inside the box, which has an encouraging ‘HiFi Made Fun’ brandished across the front, you get three cables with the DAC – a USB-A to USB-C power cable (DC 5V-rated, mains adapter not included) plus a USB-A to USB-B laptop audio cable and an optical audio cable to plug into the Q4’s USB and optical inputs respectively. So that saves you ten minutes of digging in drawers, for starters.

A coaxial completes the trio of inputs, with all three sockets capable of accepting audio up to 24-bit. As for outputs, there is a pair of RCAs for outputting the (converted) analogue audio directly to an amplifier or active speaker, and a 3.5mm jack to feed a pair of wired headphones. You get the DAC too, obviously. You get an 18-month warranty, a 30-day return period and a manual. So far so generous.

Next to the iFi GO Link (£59 / $59), which is one of our favourite tried and tested DACs in two-figure territory and has a main body no bigger than the size of your pinky with only a single USB-C input and 3.5mm output to its connectivity list, the Fosi buy looks like you’re quids in. Most DACs that cost the price of a round of drinks tend to be discreet, portable, in-line dongle designs with the purpose of being the sound-enhancing middleman between a USB-C source (whether that be a laptop or phone) and a pair of wired headphones. Fosi offers one itself

Budget DACs with multiple and various connections that have separate power feeds – such as this Fosi – tend to cross that three-figure threshold; which is undoubtedly why the Q4 has attracted so many Amazon customers. People want optical for TV sound, USB-B is still a widely used computer connection, they like bass and treble dials. It’s a proper unit with plenty of on-paper appeal.

A proper unit of compact size and modest quality, that is. There’s nothing wrong with the Fosi Q4’s visual design in the context of its cheap price – and the presence of bass, treble and volume dials will please those who value knob-feel. The close proximity between those three front-panel dials means bigger-fingered folk won't have the freedom to turn them as freely as they may want, though, and the headphone jack is slightly recessed, making it trickier than it should be to pull out headphones without accidentally knocking the input switch just to the right of it. But hey, it seems decently made and isn’t likely to sit front and centre of any room anyway. Just keep those expectations in check.

...in features at least

Performance expectations and price are almost always aligned, of course, so I didn’t expect to be bowled over by the Fosi Q4’s sound quality, just as I don’t expect budget headphones to blow me away like higher-end ones do. But in my mind, if it got even relatively close to the performance capabilities of the sub-£/$100 DACs I have heard, bearing in mind the Fosi probably one-ups them on the features front, then great – job done, Fosi.

Naturally, customer reviews should sometimes be taken with a pinch of salt – after all, it's a world peppered with fakes and funnies (I trust we have all read the Haribo sugar-free gummy bear reviews!). But that 87 per cent of 2000+ customer reviews gave the Fosi Q4 four stars (18 per cent) or five stars (69 per cent) gave me some hope. It wasn’t a great start as I hooked it up to my Macbook Pro via USB and was met with a fairly thin sound through my headphones (I tried T+A, Grado and Sennheiser pairs I knew well). A light turn of the bass dial about 45 degrees remedied some of that, though, fleshing out the bass and lower mids a little without over-pronouncing the effect, and indeed that helped communicate the attitude behind Drake’s What’s Next. The amplification was more powerful than my laptop’s output, giving greater presence to the melodic synth surges and, with the EQ shifted slightly, the hollow bass sound.

But for tonal balance and detail, the Macbook Pro’s extremely modest output was, I’m afraid to say, preferable. Despite the Fosi offering a more forthright, bigger soundstage and a boost in volume and – if you wanted it – low-end, I found its presentation tonally ill-judged and lacking the detail and even refinement in comparison. And then there was the crackling distortion I would get trying to crank up the bass a little more. Many use this kind of DAC/headphone amp to improve music from this kind of multi-tasking device where audio outputs are sadly not a priority, and the Fosi somewhat fails to perform that duty. 

I switch to the iFi GO Link and it is no competition: sonically, the iFi trumps the Macbook Pro and Fosi in every area, and pretty confidently. It was hard to switch back.

Fosi Q4

The Fosi Q4 is a rare breed offering such a spread of connections at this price point (Image credit: Future)

Two-figure alternatives?

The Fosi Q4 is a very rare example of a budget, well-featured DAC, and perhaps an okay option if all that is required is an amplification boost for a TV or whatever. It’s understandable why so many people have bought it: its price and a couple of thousand good reviews are hard to argue with for someone looking for an affordable audio boost. But for an improvement in music listening from your phone or laptop or whatever, I suggest you look elsewhere. To the aforementioned five-star iFi Zen DAC if you do indeed require a ‘proper’ unit with a suite of inputs? Sure… but it’s a third of the Fosi’s price more. Unfortunately, proven entry-level kit to hi-fi sound is often undercut by temptingly cheap alternatives on Amazon, though I’m sure some of them are decent.

There is a cheaper version of the Award-winning iFi, the Zen Air DAC, available for less than £100 / $100 which I cannot wholeheartedly recommend for the simple reason that I have not heard the thing! But I would put a modest bet on it, owing to its sibling’s success and the company’s general form.


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Becky Roberts

Becky is the managing editor of What Hi-Fi? and, since her recent move to Melbourne, also the editor of Australian Hi-Fi magazine. During her 10 years in the hi-fi industry, she has been fortunate enough to travel the world to report on the biggest and most exciting brands in hi-fi and consumer tech (and has had the jetlag and hangovers to remember them by). In her spare time, Becky can often be found running, watching Liverpool FC and horror movies, and hunting for gluten-free cake.

  • Symples
    I am most dubious of 4 and 5 star reviews on brands that I have not heard of.

    I first of all look at the 1 star reviews to find out why they do not like the product.
    I think that reveals more about a product.