FiiO Q5S Review - Amp-up your smartphone

This review is posted here in partnership with It was originally written and published by Sandu Vitalie of on Sept. 4, 2019.


One of the most advanced, if not The most advanced portable DAC and headphone amp that could be connected wired or wireless to a smartphone was FiiO Q5 released about one year ago – a marvelous piece of equipment that worked with PCs/Laptops and with Android or iOS devices alike, FiiO even developed an App for it so you can unleash its maximum potential. It looked good, it sounded great, the biggest drawback it had was in terms of wireless capabilities. FiiO was already too deep into development with it and didn’t had time to implement the newest Bluetooth chip from Qualcomm, so Bluetooth 5.0, LDAC and HWA were dropped. Wireless tech was good but not great. It of course was just a matter of time when FiiO would announce a successor for it, slightly better on few things but much better on others. Ladies and Gentlemen, without further ado, please meet the FiiO Q5S.


The volume knob of The FiiO Q5S


Newest device replaces the one-ear-old Q5 and stands as the new top-of-the line DAC from FiiO’s portfolio. Q5S comes from a long line of portable DACs and headphone amp units, it is not just a refined version of Q5. FiiO has years of expertise in the portable Hi-Fi realm and applied all that knowledge for an affordable but high-performance unit, Q5S is also a successor to the older E17K and E18, it even borrowed a lot of tech from the speedy M11 DAP so that is always good news.


Before we dig deep into it, let’s take a closer look at the box and its contents.


Unboxing Experience


The box is fairly small but thick and feels premium to me, it is basically the same box FiiO is using for the upper-class equipment. There is some thick foam padding for protection and lots and I mean LOTS of accessories inside the package, let’s check them out:

  • A black textile carry case with the FiiO logo
  • Four rubber rings to attach Q5S to a mobile source (DAP, smartphone)
  • A micro-USB to USB type-A cable for charging and PC/MAC connectivity
  • A micro-USB to Apple Lightning cable for the iOS devices
  • A mini to mini short cable (3.5mm to 3.5mm)
  • A mini to Coaxial adapter cable
  • A mini to Optical adapter
  • A silicone spacer that can be used between Q5s and a mobile source to avoid wear and tear
  • 4 additional screws for the Amp modules (so easy to lose the stock ones)
  • A screwdriver to change the Amp modules
  • Lots of paperwork (quick start guide, warranty card, notes on using it with Bluetooth devices)

That is quite an amazing accessory pack! Hats off to FiiO for putting all those together and not selling them separately.


There is just one type of cable that is missing from the package but can be purchased separately: a micro-USB to micro-USB cable or a micro-USB to USB Type-C adapter cable to connect Q5S with Android devices. Amazon and Ebay are full with this kind of cables.


Multiple angles of The FiiO Q5S


Design & Build Quality


Q5S looks very much like the older Q5 but has few notable changes. Gone is the second micro-USB port found on the right side of Q5, it made no sense since it was used only for charging, but the main micro-USB port was also charging the unit, the second port needed to go, a smart move.


The very small LED on the right side of Q5 was replaced with 4 smaller LEDs that will indicate the selected input. All in all, Q5S brought some nice quality of life improvements compared to Q5. You no longer need to guess which digital input is selected and Q5s is a bit cleaner looking.

Of course, the combination of anodized and sandblasted (with zirconium) aluminum looks amazingly good. Zirconium gave this Titanium look and will actually absorb accidental drops and scratches.


There are also other smaller details that were improved, for example the Hi-Res sticker was dropped and exchanged with two laser-engraved Hi-Res and Hi-Res Wireless logos, a nice touch. The back is covered in organic leather that gives an air of refinement and taste.


The are two things that I am not really digging: 1) The micro-USB port…seriously guys, 2020 is around the corner and you are still using 2008 tech, this port needs to go as USB type-C is the future of smart devices. 2) The edges of the device are raw aluminum edges, meaning no anodizing or sandblasting, so those are softer and easier to scratch…


Overall, I like how it looks and how it feels in the palm of my hand, it feels really solid and weighty and gives impression of being solid as brick.


An angled view of The FiiO Q5S


Buttons & Layout


Q5S is covered with lots of ports, buttons and LEDs, but most of them are set and forget or are very easy to remember what are they doing.


On top you have two ports, one is the clean Line-Out and the second one is the Line-In, the Coaxial input or the Optical input. You have a simple Low/High gain switch and a Bass On/Off switch.


The left side has 3 buttons that will work only in wireless mode: you have your play/pause/pairing in the middle, next and previous buttons.


The right side carries the volume wheel that also works as an On/Off switch and a input button that will toggle between 4 inputs, the LEDs underneath it will show which input was selected.

The bottom part is where the Amp module is located, the stock AM3E module is actually a very good and quite advanced module. I love its HP output selection as it offers a single-ended (SE) 3.5mm (1/8”) headphone out and two balanced headphone outs of 2.5mm and 4.4mm, amazing headphone connectivity! Now, of course the Amp module can be swapped, some of them will drop a headphone out or maybe will offer some sonic improvements. FiiO is selling separately a wide selection of Amp modules, but if you ask me the AM3C/D with the THX AAA module is probably the best one.




FiiO used the same Li-Po 3800 mAh battery that also powers the Q5. Since AM3E is a more powerful Amp module compared to the older AM3A, it will draw a little bit mode current and battery life is just shorter by maximum one hour compared with Q5.


You need to know that no matter what input is selected, Q5S will always draw power from its internal battery pack. Even when it is connected to a PC/MAC it will draw power from its battery for the best sound quality. All digital inputs will offer somewhere between 9 to 10 hours of playtime and on the line-in Q5S will offer a whopping 25 hours of playtime.


The back panel of The FiiO Q5S


Under the Hood


All the magic happens here as this is the only place where FiiO engineers were given freedom to come-up with an interesting and good sounding device. Q5S is stuffed with lots of top components, many of which can be found in much more expensive designs.


FiiO upgraded its internal DAC chips, the legendary but older AK4490EN were replaced by higher performance AK4493EQ DAC chips (two of them!) which FiiO is also using in their top performing M11 DAP for its super low distortion and high signal-to-noise ratio.


Q5S can finally decode up to 768 kHz/32 bit and DSD256 (x4) on the USB input.


The USB input is taken care by an advanced XUF208 interface from XMOS, that offers stability, low jitter (noise) and will send a clean signal to other components.


Q5S is using the most advanced Bluetooth chip from Qualcomm, the CSR8675 that has the widest Bluetooth codec support and uses BT version 5.0 for the most stable BT signal and for a wider range of operation. Q5S is supporting everything from the regular SBC and AAC to the most advanced ones like aptX, aptX-HD, aptX-LL (low latency), LDAC and HWA!


When it comes to raw power, the AM3E amp module is offering up to 210mW of power into 32Ω on the normal 3.5mm (1/8”) headphone out and an amazing 560mW of power into 32Ω on both balanced headphone outs, a very impressive number for a portable device. For a small comparison Q5 offered 160mW and 440mW on the same impedance and headphone output, so a really nice improvement for the loud-listeners or for diaphragm-control freaks like myself.

Low-pass filter duties are carried by two OPA1642 op-amps that are passing the signal to the AM3E amp module. The amplification stage of AM3E is formed by a combination of one JFET OPA8620 op-amp and by an additional OPA926 custom op-amp.


The same components of AM3E were used to make the AM3A module from the Q5 and from the much more expensive X7 MkII


As with the Q1 MKII and Q5, Q5S is also MFI (Made For iPhone) certified and works excellent with iOS devices, both via the micro-USB to Lightning cable found in the package and via Bluetooth. Of course, Q5S will work with some Android devices too, but no one will tell you which one exactly will work just fine with it, even FiiO can’t tell you that. It’s impossible testing the compatibility with hundreds of Android devices from different manufacturers, you will need to test that for yourself. From our tests it worked perfectly with all devices that had USB type-C and with ones that are supporting OTG Audio out.


As is the case of Q5 and X7 MKII, the headphone amp module is interchangeable, at this moment FiiO is offering several amp modules, most of them will have a unique sound signature, pick the one you like the most.


The FiiO Q5S stands with a smart phone


Sound Performance


I. Wireless Performance


My Android smartphone is BT 5.0 enabled and LDAC compatible, together with Q5S in my other pocket they worked like a team together. I was not surprised to hear a clean signal without obvious flaws. BT signal never dropped a beat and in a 2 hour walk outside they both worked as a charm.


Unsurprisingly with a pair of Master&Dynamic MW65 wired to Q5S the sound was extremely powerful, quite angry, speedy and very articulated. I couldn’t pass on this opportunity to test some faster and punchier music. Everything sounded as I remember MW65 on the big rig: punchy, imposing and very engaging. They sound quality on LDAC was as good as directly from Q5S connected to my desktop PC. A simple 16-bit PCM lossless file sounded exactly the same wirelessly via LDAC and wired. With higher quality headphones like Quad ERA-1 the same story repeats itself, close to zero difference wireless vs wired. Moving upwards to some 32bit files there is a difference, not a big one but it is noticeable. Wired Q5S sounded smoother, the notes sounded like bonded to each other. Going wireless the same 32bit file sounded not as smooth and not as biting in the upper treble region, I felt a small drop in perceived detail retrieval. Nonetheless, wireless or not, Q5S sounded great from the moment I pressed play.


I did an experiment and left my phone at the entrance of the flat with some music playing on Tidal Hi-Fi, I put the Q5S in my pocket attached to Quad Era-1. To my surprise with 2 concrete walls between us in a ~7-meter distance the signal was top notch without a single drop, only when I entered the last room with 3 thick concrete walls and about ~9 meters the signal started dropping. As you might expect, in an open space, those numbers will be much higher. I consider this a very good performance, I have nothing to reproach.


The FiiO Q5S sits on a laptop


II. Wired Performance


I will continue my final assessment of Q5S sound quality using it attached to my desktop PC and to an iPhone XR via the included cables from the package.


I was genuinely surprised that it can properly drive the Quad Era-1 planars even on the 3.5mm SE output at about 70% volume and upwards, now take into consideration that the balanced headphone out offers double the power so I would have an even higher headroom and better driver control.


Regular headphones like Sennheiser Momentum 2.0 and Master&Dynamic MW65 were driven on the low gain at about half volume, high gain was too much for them. In terms of power, I am really surprised by how much this small and portable Q5s can offer.


For pure madness and giggles I decided to power the power hungry Hifiman Arya with it, again on the SE 3.5mm output and with some loud rock tunes I was able tap my feet with a stupid smile on my face. I was smiling not because the driver control was there, or that the bass was not playing the “fart cannon” game, that never occurred, no my friends, I was smiling because this little fellow was actually driving the Hifiman Arya and if I would listen to this setup with my eyes closed I would swear I am listening to a desktop, wall-powered setup. Even on the single ended output, with the stock AM3E amp module, Q5S was more than capable of driving heavy loads. That was unexpected.


All my desktop headphones are wired with a 4-pin XLR cable, so unfortunately, I was unable to test the balanced 2.5mm or 4.4mm headphone out with bigger cans.


The side and back panels of The FiiO Q5S


Sensitive as a butterfly IEMs came to the rescue as for the FiiO FA7 I have a 2.5mm and a 4.4mm cable. First and foremost, sensitive IEMs as FA7 and many others will work wonderfully with Q5S as it doesn’t have a noise floor whatsoever. Q5S to me sounded clean of any audiophile bugs, background was noiseless and any his you’ll hear comes from the recording and not from its headphone amp. FiiO is not specifying the noise floor, but I presume it is on the same level with M11 and maybe lower than that of the former Q5. Are you considering yourself an IEM fanatic? Sleep tightly as Q5S got you covered; even multi-driver designs are having the noise-floor in check. Add the super low 1.2 Ω on SE and 2.0 Ω output on the balanced out and you could drive even 16-ohm earphones without sacrificing any of the damping factor of the amplifier. FA7 were driven on the low gain at about 40% volume on the SE out, so again plenty of headroom left even for the most demanding DSDx4 or 32bit PCM recordings. Going balanced I was driving them on 30% volume, with a larger soundscape around me and with a tighter driver control. Exclusively for IEMs and for regular portable headphones, a much better and much more expensive setup, be it portable or desktop will be just overkill. I mean FA7 and Momentum 2.0 sounded almost indistinguishable from a 6K desktop setup to Q5S.


What was quite astonishing from the first moments I pressed play was the size of soundstage and the pin-point imaging Q5s was capable of showing-off. Majority of AKM designs are sounding quite open and wide spread, but Dual AKM designs are completely different animals. There were few tracks where left to right passages sounded almost disjointed and as different entities. There is just a bigger space between both channels and I have a longer time discerning and digesting all that information. In terms of soundstage size Q5S is playing with the best portable devices on the market. It has the same or even bigger soundstage size of M11 DAP and that says a lot as M11 was already a top-performer in this regard.


Q5S is portraying music on all axes and I could actually appreciate the distance between each instrument and how far away are those from me. Live recordings are gaining this epic feel and regular recording are having an improved layering around each and every note.


The side panel of The FiiO Q5S


When it comes to frequency response, I do feel Q5S puts most of its attitude in the bass and in the midrange area but will tickle your ears even with sub-sonic trebles. Now, again this is a AKM based design so harshness and edgy treble is nowhere to be found, Q5S is free of any of that.

There is a mild change compared to older Q5 and even to M11 DAP, I do feel the sub-bass performance is better on the newest Q5S. There was a small drop on the older devices, a mild one and I do feel Q5S rumbles harder my ears on my usual bass tracks (without engaging the bass switch). I do feel Q5S presents the sub-bass in a very linear and straight manner, without drops is this region. Any bass-heavy track I would put on would instantly raise my engagement and mood levels.


Mid-bass and midrange area are two of the best parts of Q5S, there is just nothing to complain about this area. Bass is always full and enveloping sounding without being overdone or muddy, just right. I spotted layers of it and I spotted it breathing and moving quickly around. It comes fast, kicks you hard and runs away as quick as it came.


Midrange is quite smooth and life-like most of the time. Voices are deep and soul-reaching on the right tracks. This is a technical and a musical midrange performance in a single box, my kind of performance.


Treble is not really like a chameleon and sends a clear message from the start. Yes, it is smooth, yes, it is easy going, yet it is also extended, very much so in the upper-region. It has sparkle, but not a lot of it. I know personally people that feel treble should be bright and sparkly and very present but I am of a different opinion. Treble has definition, texture, sounds clean and detailed, however it doesn’t scream around or attracts attention to it. It is not sharp, bright or emphasized, if you are looking for this, you search will continue shortly.


Probably the most impressive aspect of the Q5S is how authentic it sounds; it is very courageous somehow. It resembles a lot more a desktop unit than a portable device. If I am raising the volume the dynamics would increase as well and even at maximum volume it never clips or distorts.


As a whole package Q5S is punching with authority and hold its chin-up even compared to desktop units, as much as I would like to bash it, there isn’t a serious downside in its performance.


Two of The FiiO Q5S on a table


An interesting comparison


FiiO Q5S VS FiiO Q5


I’m glad to tell you that a Q5 made its way to me and I could compare both brothers in arms. From the first beats it was clear that Q5S has more power under its belt, I need to raise the volume by about 10% to have the same sound pressure level (SPL). Once I volume matched both using the sensitive mic inside the MiniDSP E.A.R.S. I resumed my listening session.

Both are sounding very alike and indeed have a lot in common. Nonetheless, Q5 is not that authentic sounding, it is a bit shy sounding in term of dynamics. Listening to the symphonic metal of Epica revealed that Q5 is not as engaging and is limited in terms of dynamics. I am not really sure if the newest DAC chips or the higher amplification factor was at play here, maybe the whole package is just delivering better dynamics and a result a better blood flow to induce euphoria to the listener.


Q5 sounds like a transition from a portable to a desktop device, whereas Q5S is sounding like a grown-up desktop device.


Listening to high-caliber recordings from Chesky or Reference Recordings revealed an additional layer of air around the notes on Q5S and an additional layer of information, especially small nuances were easier to spot on the newest device. In terms of frequency response both are very alike, but Q5 on some records will bite more in the treble area, it is not more detailed in the treble, just attracts more attention to it. As a result, Q5S sounds like a complete linear experience and Q5 is like having a small emphasis up-top.


The FiiO Q5S next to a large amplifier




I will keep it very short since I believe there is no contest between these two. Both are using the same DAC chips; the difference is that Q5S has two of them. As a result, with Q5S everything is more layered and airier. I no longer need to stress myself too much to locate all the sounds and appreciate their distance to me. Q5S is more detailed sounding, wider spread and deeper as well.


K5 PRO has a much stronger amp section but it is not as clean as the one from Q5S. With K5 PRO you are gaining a lot of power in exchange for the cleanness and airiness that Q5S is offering back. Q5S is no doubt a much better device for IEMs, portable headphones and desktop dynamic headphones. For difficult loads and planar-magnetics it is almost a tie, since K5 PRO will offer a better grip, control and engagement level, vis-à-vis a larger, clearer, more layered and breathable sound of Q5S.


I still prefer the mighty Q5S as its internal amp section can still be improved upon.




I disliked the aging micro-USB port and the raw aluminum edges of Q5S.


However, when it comes to sound performance, Q5S shown attitude, balls and lots of control even for harder to drive headphones. IEM users can sleep tightly as Q5S is exactly what doctor ordered.


It is small and portable, yet the sound it produces is grand and wide and that can be spotted from the first moments. It really resembles a high-quality desktop DAC and headphone amp unit.


If you want to send an unaltered Bluetooth signal to it, the best Bluetooth codecs will come to the rescue, as at this moment Q5S is supporting all the best BT codecs including the widest range from the BT version 5.0.


It really deserves the flagship status in FiiO’s DAC/Headphone amp line of products, at $350 I consider it better sounding than the on-stage Chord Mojo and at this price you can’t go wrong with it.


I recommend getting it from here (Apos is offering free shipping in the USA, free 30-day returns in case you don’t like it, an extra 1 year of warranty and lowest price guarantee).



  • Elegant and simple design
  • Solid build quality
  • Widest Bluetooth codec support and the best BT range thanks to version 5.0
  • linear frequency response, extended on both ends
  • Bold, punchy and impactful sounding
  • No harshness/brightness whatsoever
  • Great detail retrieval, clean and airy as well
  • Impressive soundstage size, depth and layering
  • Powerful headphone amp section
  • Lack his with sensitive IEMs
  • Has an impressive value


  • Aging Micro-USB port
  • Lack of a micro-USB to micro-USB/USB Type-C cable in the package
  • Raw aluminum edges are prone to scratches


  • Sources: Xiaomi Mi Mix 2S, Alienware Aurora R7
  • DACs: FiiO Q5S, Q5, K5 PRO, Matrix Audio Element X
  • Headphone amps: Benchmark HPA4, Erzetich Bacillus, Headamp Gilmore Lite Mk2
  • IEMs: FiiO FA7, IKKO OH1
  • True Wireless headphones: Creative Outlier Air, Hifiman TWS600
  • Full-sized headphones: Hifiman Arya, Quad ERA-1, Sennheiser HD660S
  • Wireless headphones: Master&Dynamic MW65, Sennheiser Momentum 2.0 Wireless
  • Loudspeakers: KEF LS50W
  • Interconnects: QED Reference XLR, Aune AL3 XLR
  • Power Cables: Isotek EVO3 Premier
  • Balanced Power Conditioners: PLiXiR Elite BAC 400, KECES BP-600

The FiiO Q5S lying on top of an amplifier