This is a product review of the TOPPING A50s Headphone Amp, which is available for sale now on Apos.
How Topping is even operating in times like these, it’s a big mystery to me. I know several audio manufacturers from Europe that are not accepting orders anymore, just because their factories are barely working due to Covid-19 lockdown, yet Topping is releasing several new DACs and a handful of high-performing, great-measuring headphone amplifiers quarterly. Ever since publishing my A90 review in June, soon after two new NFCA based headphone amplifiers were released: the little-big-amp L30 and another cutie, the A50S that I will be testing today. There is another NFCA amplifier in the making that will stay somewhere in between A90 and A50S which will probably shake the affordable headphone amp market yet again. All in due time, patience my fellow enthusiasts, you’ll hear more about it sooner than later. Topping even released a word class preamplifier by the name of Pre90 which I’m also dying to compare with my Benchmark HPA4. Seriously now, are those guys ever sleeping at night? I know several hard-working audio-brands out there, but Topping climbed that mountain and put a flag on top of that list. I sincerely cannot keep up with the reviewing process with so many products coming from Asia, especially with gear made by Topping and by its direct competitor SMSL Audio.
A50S is not yet another NFCA Amp, instead it replaces the A50 that I’ve reviewed last year and it tries to complete a beautiful stack consisting of a D50S DAC and of a P50 power supply that can power both devices at once. In its stock form, A50 wasn’t the best match with D50S, mostly because both were extremely good in the treble region, but less so in the midrange. I’m curious if A50S would solve all issues of its predecessor, so let’s dive deep and find that together!
As with all Topping products, A50S came double boxed and carefully packaged. There is lots of foam inside for extra protection. It is so Topping seeing extremely detailed measurements in its user manual like total harmonic distortion plus noise and the frequency response made with one of the best audio analyzers on the planet. I’m very glad to see them in the user manual and I’m also glad they are not using some funny marketing tricks, colorful graphics and are always straight to the point, with just pure facts and real specs. There is also a warranty card that doubles as a product catalogue, just in case you want to know about their latest and greatest. A50S is also coming with a universal external switching power supply and with a headphone adapter, so you could use headphones terminated with 3.5mm (1/8”) jacks on its 6.35mm (1/4”) output. That is basically it, no bells and whistles, exactly what you need to start your listening session.
Design & Build Quality
I have already tested their D50S DAC, their A50 plus their P50 power supply and A50S looks pretty much the same and by that, I mean really attractive, sleek and beautiful. Tolerance numbers are great, it is carved from a single aluminum block, reminding quite a lot about a dwarf-sized MAC Mini. It’s very small, but once you lift it up (456 gr or about a pound) it gives an impression of a really well-built unit. With its clean unibody design, obviously there aren’t any visible screws to be seen, you can spot them only underneath it. I find its fit and finish excellent and considering how small it is and its tiny while LED, it gets a huge WAF, it is really invisible to feline eyes. I wish more manufacturers would put a bigger importance to looks and build quality. A50S and the rest of the fifties line are affordable units, but are looking like expensive men jewelry to me.
The volume knob is not wobbling at all and you’ll need to apply a bigger pressure to rotate it, which I personally like. Its corners are rounded, so you won’t cut yourself with them or cause damage to your precious headphones. Seriously now, the only thing I dislike about it, are those 4 foam dots that are used as small feet, A50S case is already working as a huge heatsink cooling down its internal circuitry, yet I would like to have some taller feet, some rubberized semi-spheres would look much nicer than the stock ones.
Controls & I/O
A50S as its predecessor is a simple and straightforward device, it can work as a single ended or balanced headphone amplifier or as a single ended preamplifier, alas without a remote so I don’t expect it to be used that often in a proper loudspeaker setup, maybe with some powered loudspeakers in front of your PC.
On its front panel, from left to right there is your On/Off button, once it is powered a short press will change the gain setting from low (0 dB – unity gain) to +6 dB, there is a 6.35mm (1/4”) jack, and a 4.4mm balanced jack. Its predecessor A50 had a 2.5mm balanced jack instead and I kindly suggested replacing it with a 4.4mm jack, since it’s sturdier, has a bigger surface area, a better current delivery and a lower resistance. It seems that my prayers have been heard, thank you Odin! On the far right is your volume knob and that is pretty much it.
On the back, A50S has a pair of RCA inputs, a pair of RCA outputs in case you’ll want to use as a preamp and a 15V DC input.
Under the hood of A50S
Before I move to the unit itself, I’m a little bit disappointed that A50S is coming with an external switching mode power supply, instead of a linear transformer-based power supply like their L30 headphone amp was coming with. Even right now, I can assure you that its P50 external regulated PSU that you can purchase separately, should perform better to the stock one, lowering its noise floor to inaudible levels, a thing that I can’t say about the stock one.
As for the tech inside it, Topping put in that CNC roll-cage the same ultra-high-performance and ultra-low-noise NFCA (Nested Feedback Composite Amplifier) modules that are being used in their A90 and L30 headphone amps. Topping redefined the Nested Feedback topology (that is well-known to have a lower-gain and a weaker power output), by employing an Ultra High Gain Feedback and a Voltage Current Hybrid architecture. If this sounds like some gibberish non-sense, in simple words, the biggest drawbacks of the composite amplifiers (low-gain, low power output, increased resistance) were dealt with and those are no-longer apply to the Topping analog designs. I believe they deserve a round of applause! Hats Off to Topping for making small electronics powerful and clean sounding, without traces of distortion, as eons ago that wasn’t even possible.
As for power output, this tiny monster can output some serious punch, more exactly 3.5 Watts in 32 Ω on its balanced output and a max power of 1.4 Watts on its single-ended output. That is a lot of power, considering its diminutive size and its low power consumption. Truth to be told, there aren’t any other headphone amplifiers of the same size that can output as much power. Its smaller brother L30 outputs slightly less, more exactly 2.3 Watts in the same impedance and if you would like to upgrade from that one, A50S is offering more power while holding its distortion as low.
Other than that, A50S has a much better channel crosstalk of -128 dB on its balanced outputs compared to just -86 dB on its 6.35mm jack, meaning that the impression of a breathing type of sound and of a larger soundscape will definitely happen on its balanced output.
While it doesn’t have balanced inputs to form a proper BAL In > BAL Out setup, it offers double the power via 4.4mm and a much lower channel crosstalk, that is extremely beneficial with any types of headphones. Output impedance is negligible at just 0.1 Ω on SE and 0.2 Ω in BAL, you can be sure that A50S will preserve all the damping factor for an immaculate drive and transient response.
If you want to squeeze most out of it, I strongly recommend using a DAC or any kind of analog or digital source that can output at least 2V on their RCA outputs, but if you want the best out of it, I recommend a source that can go slightly higher than that. Luckily, I have a high-end Audiobyte HydraVox at my disposal that offers up to 3.8 Volts on its RCA outputs that sounded absolutely gorgeous with A50S. I only briefly used it with a Matrix Audio Element X, as in this particular setup HydraVox sounded better to me. A50S was driving all sorts of headphones, starting with ultra-sensitive IEMs, to portable over-ears and then to desktop headphones, so I will be squeezing everything it can put on the table. Alright everyone, enough with the talk, let’s listen to some tunes!
I. Preliminary Impressions
It is funny driving a pair of some very inefficient Hifiman Arya and then a pair of Audeze LCD-4 on its regular 6.35mm SE output and see them taking flight, driving them fully with an amp that is no bigger than my palm. HydraVox DAC with its 3.8V output is giving a huge helping hand, unlocking the full potential of the tiny A50S.
So, how does it sound? In few words it is extremely clean and transparent, lightning fast, punchy, articulate and amazingly good when it comes to frequency response. When it comes to things like ultimate transparency and detail retrieval, nothing can hide from its gaze as it is as transparent as headphone amplifiers could ever be. In this regard, this $199 metal box is on the same level with a $3000 Benchmark HPA4, with a $2500 Sparkos Labs Aries and it’s on the same level with a $500 Topping A90. With some extra tinkering, Topping made it vaguely more natural sounding compared to THX AAA-based amplifiers. Its bass delivery, even from the lowest octaves is nothing short of spectacular, it has enough current delivery to drive desktop planar magnetic headphones and not going to lie that I really enjoyed my time with an amp this small and affordable that stood shoulder to shoulder with pricier amps. I would really want its successor, whatever name it would have, to use Mini-XLR inputs instead of RCA inputs, so it would perform as a true balanced in > balanced out amplifier and the same can be said about the successor of the D50S DAC. Just imagine a palm sized desktop setup that is fully-balanced from input to output, that would be something worthy to carry around in 2021.
Sadly, I don’t have the L30 with me anymore, but I remember it struggling with a 735-gram Audeze LCD-4, incapable of providing a decent headroom on the volume pot. In comparison to that one, A50S feels like a pocket rocket when it comes to driving difficult headphones and I was very surprised that it could even decently move a pair of Hifiman Susvara on its 4.4mm on max volume.
Of course, it can’t be considered as an end-game, delete your head-fi account kind of amplifier without some cons and quirks, here and there right? I find it having a somewhat limited soundstage on its 6.35mm output and a little bit of noise with ultra-sensitive IEMs, but more about that in the following chapters.
II. Noise Floor
Most amplifier designers might tell you about their distortion numbers but not about noise floor of their amplifiers, mostly because it is difficult having both in check. About two years ago everything changed when THX AAA modules hit the market, those came as a storm smashing every record with their extremely low THD and noise numbers. Topping smashed all previous records with their NFCA modules and if Benchmark HPA4 had it at 2.4 microVolts at full power, Topping A90 has it at only 0.9 and its smaller brother A50S has a noise floor of just 1.1 microVolts. Considering its low price point and its switching mode power supply, that is really impressive if you ask me. Years ago, that wasn’t possible even with price-no-object amplifiers.
I still wanted to test both headphone outputs checking if gremlins are living inside its case and in this regard, FiiO FA9 is still my numero uno IEM in detecting any type of noise. After flipping a switch and putting them in high-sensitivity mode, with 113 dB per 1mW of power, only very few units passed this test with flying colors. Pausing my music and going to max volume, the noise floor is rising and that can be easily heard. No matter the output or even the gain position, there is a little bit of residual noise close to max power. However, at my normal listening level of 85 to 90 dB, I cannot spot any kind of noise if I’m pausing my music and in some ways A50S seems to be an IEM friendly amplifier. Meze RAI Penta, FiiO FH7 and LittleDot Cu KIS detected a much lower noise floor, almost invisible at max power. In this regard, both A90 and L30 performed better, as I didn’t spot any noise out of them whatsoever even at full power. I presume that its switching power supply is the culprit and there is a chance that P50 could completely solve this issue.
There is another con that I don’t find disturbing: on the lowest volume position, sound is still leaking via sensitive IEMs. No biggie for me, but it still needs to be mentioned. Other than that, via portable and desktop headphones, I didn’t spot an increase of the noise floor and it performed in a very clean manner. I didn’t spot hums, buzzes, any hissing, just a pitch-black background and lots emptiness around the notes, improving the transparency and sharpness of the musical notes.
III. Resolution & Transparency
I’ve approached the easiest chapter to write about, as in reality A50S is a very detailed and transparent sounding amplifier and it is very true to the source, slightly altering the frequency response which I’ll mention later on. It reminds me a lot about its brothers like A90 and L30 and I strongly believe that A50S performs pretty much the same. At full power, A50S has a THD (Total Harmonic Distortion) of 0.0007%, meaning that no matter how hard you try, you will be hearing the distortion of your headphone drivers and maybe of your DAC, but definitely not of the A50S. It doesn’t add anything in here, it’s a wire with gain amplifier that just disappears from your acoustic chain. Smallest nuances and micro-details have nowhere to hide, A50S will easily show them to you with a nicer pair of headphones. I’m personally extremely happy that we approached times like these, experiencing high-end sonics at a price that anyone could afford. It is a good feeling knowing that you aren’t limited by your amplifier or DAC, but only by your headphones.
I’ve compared it back and forth with a SMSL SH-9, based on flagship THX-AAA-888 modules and sometimes I’ve had a feeling that SH-9 was clearer and more transparent sounding, especially its treble delivery was sharper somehow, cymbals for example felt metallic with a very clean leading edge, whereas on A50S those weren’t that sharp and defied. Honestly, the difference is not that big and both units were unveiling a lot of info, including in the upper registers. There was a clear difference thought, as A50S had a bolder bass performance, it wasn’t clearer, it just had more or it quantity wise, leaving an impression of a darker sounding amplifier.
Compared to other non-THX and non-NFCA amplifiers, I can guarantee that A50S will unveil more information from your tunes, more bass layers, more treble textures, more micro-details and small nuances, it is really good in discovering imperfections of your music and if resolution is your thing, you cannot go wrong with A50S.
IV. Power Output
As you can expect, the little A50S was driving all sorts of portable over-ear headphones and multi-driver IEMs with ease. High-gain or balanced power wasn’t even needed with such loads and there was a huge headroom left on tap as I couldn’t go louder than 12 o’clock power wise. Amazing driver control followed, a very nice transient response, a full-rendering of the frequency response and everything delivered in a clean, transparent and detailed way.
The difference between both headphone jacks is sincerely not that big with such headphones and I’m suggesting using IEMs on its SE output and everything else on its BAL output.
Moving on to desktop headphones as Ollo S4X Reference, Erzetich Mania, Kennerton Magni and Gjallarhorn, again not that much power was needed to drive them to ear-bleeding levels. I liked low-gain and balanced output the most with these ones. There was a much bigger difference between both outputs, especially with open-back headphones on balanced out music felt more layered, airier and the distance between the most far-right and far-left sound felt bigger in a way. I simply had a larger soundscape in front of me at the expense of a less dense and meaty sound.
Moving on to big-league headphones, I wasn’t surprised that both Kennerton Wodan and Erzetich Phobos – two outstanding planar-headphones needed only about 30 to 40% of power on high-gain and balanced output to be fully driven to their maximum. I was rocking out with both, dynamics were really impressive, headroom left of tap was bottomless, bass notes were hitting my skull relentlessly and it really controlled those two down to the lowest octaves. I really don’t suggest a pricier amplifier with headphones like these and I’m pretty sure it would be more than enough with Sennheiser HD6XX line, Beyerdynamic DT line, with AKG K line (expect for K1000) and it would be a walk in the park with any Focal or Grado headphones.
Hifiman Arya and Audeze LCD-4 have pretty much the same sensitivity and A50S was driving them to loud levels at about 2 o’clock position on high-gain and BAL out. These were the only headphones that I’ve felt that ultimate slam and punch into my ear-drums wasn’t up there with the best. A90 was better in here, SMSL SH-9 did also provide a nicer impact and of course pricier amplifiers like Flux Lab Acoustics FA-10 and Benchmark HPA4 were absolute rulers in terms of power and ultimate driver control. Nonetheless, the little A50S was driving them very good, there was enough volume, dynamics were quite impressive and the sound didn’t collapse on me. I wished only for a nicer slam and for more air around those notes, as everything else was already there.
V. Transient Response
A50S wasn’t slowing down any headphones I’ve tried with it, on the contrary it was flooring the gas pedal, increasing the pace, rhythm and timing of most headphones. If your headphones do not require too much more power to be moved, then A50S will be proving a faster pace and a decent punch and slam into your eardrums. It certainly didn’t have any issues with Kennerton Wodan on the SE output and it was snappy and engaging with Hifiman Arya on its balanced 4.4mm output. I don’t have the older Topping A50 with me anymore, but I strongly believe the newest A50S is considerably better in here, as it sounded engaging not only with dynamic headphones, but with planar-magnetic ones as well.
A50S presents music in a nimble and agile way, it’s fighting in lightweight category so don’t expect very long decays with blues or jazz, as it would happen with tube amps and with few class-A amplifiers. On the other hand, modern music was truly a delight with it, it was keeping up with faster beats, striking fast and ready to do it again. The only area where A50S didn’t shine bright compared to its bigger brother A90 was the thump / slam department. It didn’t pound as hard and didn’t deliver the amount of air needed to feel the music with your whole body, it was good in terms of slam but not exemplary as A90 was. Multiple factors are at play here, it’s limited power output, its limited capacitance stored and of course that switching mode power supply is restricting its performance.
In its defense I will remind you, that it has a close to zero output impedance on both headphone jacks, meaning that damping factor would not be affected in any way. It is fully preserved, resulting in a lightning-fast start and stop of the drivers and in a perfect diaphragm control.
VI. Soundstage & Depth
The little one has a decent soundstage size on its own but it’s important to know that soundstaging capabilities are influenced directly by the source that is connected to it. HydraVox DAC that I’m using with it, is among the widest and deepest sounding source I’ve tried so far and it shouldn’t be a surprise experiencing a bigger void space between each and every note even on its SE output. Connect it to a forward sounding source and this chapter would feel completely different.
Its predecessor wasn’t that impressive in here, A50 sounded closer to the listener, upfront and personal most of the times. A50S is a higher tiered device no doubt and doesn’t sound claustrophobic to me at all. Of course, it’s power output and its headroom are playing big roles in here, A50S is very good in those areas considering its weight and size and all that had a positive effect on its soundstaging capabilities. There is plenty of air if I’m driving a pair of Kennerton Wodan or Erzetich Phobos, but less so if Hifiman Arya or Audeze LCD-4 are coming to play. Nonetheless, I liked how it meticulously placed everything precisely in the scenery, it has a very good 3D imaging and a very sharp one too.
I’m pretty sure it would sound nicer in here with that P50 power supply as it was the case with A50 and if you really want to squeeze the best out of it, P50 should be on your radar.
VII. Frequency Response
This chapter alone will feel very much like that of A90 and L30 because all three amplifiers were voiced the same.
Sub-bass is something that still boggles my mind. It’s very good in here, spectacular even, it wasn’t a moment when I felt it lacking in quantity or quality. It was always visceral; it was hitting relentlessly in a very pleasant way. My electronica collection sounded exactly as it did on bigger amplifiers. Bass went deep and reached those 20 Hz notes; I didn’t even need to check it with the MiniDSP E.A.R.S as it was very obvious from the start. It actually felt a bit more energetic in here compared to THX-AAA amplifiers and it added just a hint of warmth and smoothness that isn’t present on those ones. Mid-bass felt exactly the same, it was as snappy, as fast and as hard-hitting as sub-bass was. I really don’t have much to complain in here because it felt extremely clean and precise, but also powerful without being overwhelming.
Midrange was something that impressed right away. While it isn’t that meaty and doesn’t blossom as much as it does on Burson, Audio-GD or Flux Lab Acoustics units, it is by a hair warmer compared to THX-AAA amplifiers and that makes human voices standing out in a crowded track. Mid-tones are nicely rendered, there is plenty of meat to the bone, string-based instruments were weeping nicely adding just a pinch of naturalness and warmth into the mix. I consider it having a neutral type of midrange that is leaning towards sweetness and boldness. This type of midrange is improving quite a lot any headphones of Hifiman which are known to be thinner and less impressive in here.
Treble is really precise, it’s defined, detailed, it has a sharp leading edge, but without adding a brightness filter all over my music. It isn’t rolled-off at all, even past top-octave it felt detailed and it was ringing nicely with headphones that can show all that treble to you. At first listen it might appear as slightly rolled-off in here, mostly because bass and midrange regions are faintly accentuated, but after few minutes that turned into hours, it was clear to me that it isn’t lacking treble energy at all. It’s predecessor, had more treble ringing and a higher distortion in here, which made it a troublesome partner with D50S DAC. A50S on the other hand feels like a soulmate for D50S, it should pair much nicer and together should provide a better tonal balance without shifting too much to the bright side.
Overall, the frequency response feels complete, there aren’t gaps or roll-offs in there, just an extended frequency response with a slight bump in the bass and midrange region, that are adding plenty of emotions and a much needed soul in the music.
VIII. A Comparison
Topping A50S ($199/€199) VS SMSL SH-9 ($290/€320)
I’m listening to both units for about a month now and I feel like I know them very good at this point. I wish I had a Topping A50 as well, that would be a much nicer comparison to make, alas I don’t have it anymore, so I’m comparing it with SH-9, that is very close to it price wise.
SH-9 is not a huge amplifier by any means, it is small and quite lightweight and can also be used in tiny setups, maybe in your office or just before bedtime like I’m doing. Build quality wise, I actually prefer the little A50S, mostly because its milled from a single block of aluminum, it really looks like a tiny version of MAC Mini screaming a high-build quality. Its volume knob is harder to turn and I like that more, especially while listening to sensitive IEMs that require tiny amounts of power to be driven.
Speaking about IEMs, SH-9 was a clean winner to me, because it was simply dead-silent even with FiiO FA9, without any traces of noise floor. A50S wasn’t bad at all, but there were traces of noise at a higher listening level and it didn’t have a pitch-black background. At normal listening levels I could hardly differentiate both units, yet again SH-9 felt simply clearer sounding to me, so it’s a clear win in favor of SH-9.
Moving on to desktop headphones, both units are very capable of driving harder loads, but of course SH-9 was a higher output of 6W in 16 Ohms, meaning that it didn’t have issues driving headphones like Audeze LCD-4 and Hifiman Arya, which sounded great on A50S, but not spectacular. In its defense, A50S has a vaguely different tonality and instead on focusing on absolute linearity, it adds a pinch more bass and midrange making bright sources and headphones a lot more manageable. There are plenty of detail-oriented sources nowadays that are putting treble presence above anything else and A50S should work much nicer with such kinds of sources. With dynamic headphones that don’t require that much power to be moved, I wouldn’t be surprised if people would prefer the A50S in detriment of a more powerful SH-9. Beyerdynamics, most Sennheisers and all Grados should perform better on A50S and most planar-magnetics should perform better on SH-9.
When it comes to depth and imaging both performed pretty much the same, but when it comes to soundstage, SH-9 went slightly ahead and pushed those notes farther away from me, creating a bigger air-bubble from which I was picking only the sounds I wanted. In terms of details and transparency, I find both units on the same level, both were able to reveal everything that is hidden in my music, everything appeared defined and sharp, with a clean leading-edge. I’ve heard the last layers of micro-details loud and clear and in this regard, both are performing like my reference Benchmark HPA4.
Frankly, the only areas where A50s was losing ground to SH-9 was output power, soundstage size and background noise, as everything else felt pretty much the same. Tonality wise I prefer the warmer A50S to that extremely linear sounding SMSL unit. If you already own the SMSL SU-9 DAC, it is normal choosing the SH-9 that will compliment it visually and sound-wise and pretty much the same can be said about the Topping D50S DAC paired to A50S - creating a tiny, but powerful and capable setup that could drive almost anything out there.
I really like the sound of nested-feedback composite amplifiers like Topping A90 and L30 and if I would never test that Flux Lab Acoustics FCN-10, I would surely award the A90 as the best headphone amplifier I’ve heard in 2020. I have the same feelings about the tiny A50S, it is really impressive when it comes to technicalities as speed, decay, details, transparency and frequency response. It definitely performs like an NFCA amp, only at a smaller scale as it has about half the power of A90 at a third of its size.
It put a wide smile on my face when it was driving a pair of Audeze LCD-4 at 1 o’clock position offering plenty of headroom and goose-bump inducing dynamics. If there would be a definition of a universal headphone amplifier that has proper high-end sonics without destroying your wallet in the process, then that will surely be the Topping A50S!
Topping A50S was kindly provided by Apos Audio, it can be purchased from their web-store by following this link. You can also go for the 50S Ensemble consisting of a D50S DAC + A50S Amp + P50 power supply at a pretty discount right 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 they will price match any price you can find online).
If you get one, please come back and leave a comment, I’m curious to know how it performs in your headphone setup!
Small, cute and sleek looking device
Very solid build quality with an unibody case
Extended frequency response at both ends
Excellent sub-bass delivery with an amazing quality and quantity
Fuller mid-tones, plenty of naturalness
Feels linear and neutral with a slight warmish tint
Fast and energetic sounding
Surprisingly powerful considering its size and weight
Drives almost anything on its balanced output
Precise pin-point imaging, quite 3D sounding too
Decent soundstage and layering via its 4.4mm output
A very good value
A real space saver
Traces of noise on higher volumes with ultra-sensitive IEMs
Slam could be better
Soundstage wasn’t that impressive on its regular 6.35mm headphone jack
Sources: Xiaomi Mi 9T Pro, Corsair One i160
DACs: Audiobyte HydraVox + HydraZap, Matrix Audio Element X, Flux Lab Acoustics FCN-10, Soncoz SGD1, Burson Conductor 3X Performance
DAPs: Shanling M6, FiiO M15
Headphone Amps: Topping A50S, SMSL SP400, SH-9, Benchmark HPA4, SparkoS Labs Aries, Flux Lab Acoustics FCN-10, LittleDot MKIII SE
Power Amps: KECES S300
IEMs: FiiO FA9, FH7, Meze Rai Penta, Rai Solo, LittleDot Cu KIS & lots of other lower tiered ones
Portable headphones: Sennheiser Momentum 2, Meze 99 Classics
Full-sized headphones: Hifiman Susvara, Hifiman Arya, Audeze LCD-4, Erzetich Phobos, Erzetich Mania, Kennerton Wodan, Magni & Gjallarhorn, Quad ERA-1, Ollo S4X Reference
Loudspeakers: KEF Reference 3, Buchardt S400
Interconnects: QED Reference (x3)
Speaker cables: Kimber PR8, Audioquest Type4
Power Cables: Isotek EVO3 Premier (x3)
Balanced Isolation Power Conditioners: PLiXiR Elite BAC400
Overall score 87/100
Power Output 84/100
Frequency Response 93/100
Stage Size 79/100
Build Quality 86/100