LittleDot MKIII SE Review – A tube headphone amp with solid state roots

My Video Review:

When LittleDot MKIII SE (which I will be simply calling LD3 from now on) landed at the front of my door, a flashback struck me and a lot of good memories rushed in. Long before my xDuoo TA-10 and TA-30 reviews, before my Woo Audio WA6 Special Edition review and even farther away down the memory lane, I was purchasing my first tube-based headphone amplifier. I was curious to know what is the fuss about those tubes and what is so special about them. Soon after, I’ve become a proud LittleDot MK1 (without the “+” that is currently for sale) tube-based headphone amp user and in no time, I was already rolling tubes in it. I started researching about current production and New Old Stock (NOS) vacuum-tubes and was trying to find a pair that would suit my musical preferences. I remember paying a lot for a pair of matched Western Electric tubes, those two raised the value of that amp but about 50%. Being a student at that time, most of my colleagues were buying books, but I was picking and rolling tubes in my freshly acquired LD1 with a wide smile on my face. Curiosity struck me even harder, as I started experimenting with R2R DACs with tube output stages, I’ve tried tube power rectification in higher-class tube amps and sadly, never went back in trying a higher-tier LittleDot amp.

The wheels of time are turning and somehow, I’m again listening to R2R DACs with a tube amplifier on my table. Today I will be testing a hybrid headphone amp from LittleDot, it is their mid-range model that is not that hard on the pocket, but shares a bit of DNA with its bigger and more expensive brothers.

If you would come from a solid-state amp to an all-tube amp, the change in tonality might be too much for you, quite a few are still not embracing the tube movement and I don’t blame them for that. However, a hybrid design as this one should be considerably lighter on your ears, there is still a bit of tube goodness in there, but a nice speed and transparency too thanks to its solid-state output stage.

I will say it from the start, that LD3 review sample was provided by LittleDot distributor from USA. Since I am as independent as possible, you have my word that this will be an honest and unbiased review. So, let’s get it started!

Unboxing a little .

Unboxing experience was positive as it came double boxed in a thick card-board and the product box was filled with tons of white foam for protection. LD3 is not that heavy, still it was well protected on all sides during shipping. It was odd seeing the tubes siting in their sockets and not somewhere near the amp, but considering that Little Dot is getting those 6N11 tubes in bulk, it does make sense now. Besides the usual paperwork as a user manual and a limited warranty, I was quite surprised to find two pairs of interconnect cables in there too. A nice pair of RCA cables and a pair of half-a-meter XLR cables, that was unexpected and I do hope that the final retail box contains all these goodies as well.

The user manual is in English, you can find everything about it, including tube substitutes for 6N11, just in case you’ll go berserk with the tube rolling.

Design & Build Quality

I just realized that in all this time, Little Dot didn’t change the appearance of their amps at all. Sure, newer products were released with few wooden accents, but their older designs like MKI, MKII and MKIII are looking exactly as I remember them.

LD3 is having a metal body, it is painted with a glossy black paint – I wish it was a stealthier matte paint, that would be less impactful on the eye. My wife already asked what is this Sputnik on my table and obviously a lengthy explanation followed. WAF factor is quite low if you ask me and I wish it looked less flashy on the outside. The front panel has a raw aluminum look and the top plate with the tube guards has golden accents, that again captivates the cat eyes of our loved ones. An all matte black or matte silver would look simpler and classier too. Other than the paint, the device itself is pretty heavy. At about 3 kilos (or 6.6 pounds) it looks pretty serious on my table, but thankfully it is not that huge in an office desktop setup. It is about the same size with mid-level DACs, so it could make good partnership with something like a Topping D90 / DX7 Pro or SMSL M400, just in case you’ll want a bit more warmth in your music.

I like that Little Dot put some soft rubber feet underneath this one, which are longer compared to the ones I’ve seen on solid state amps, meaning that heat dissipation shouldn’t be a big problem. The front and back panels are moderately thick, but still made out of aluminum, so nothing to be worried about.

Just in case you are wondering: you cannot remove the tube guards, but knowing how often I am switching my headphones and how many times I walked outside the listening room with headphones attached to an amp, it is safe to say that having those guards in place should better protect your investment.

Controls & Connectivity

Since this is an old-school headphone amplifier, without additional functionalities, bells and whistles, you are basically limited to some headphone outputs and some analog inputs. On its front plate you will find a 6.35 mm (1/4”) headphone jack, another 4-pin XLR balanced headphone out, a huge volume knob and a small LED on the far right that will show its working status. LittleDot chose a blue LED in there, there is always a debate somewhere online, which LED color is cooler looking? Blue, red or orange LEDs. I personally don’t care that much as long as they aren’t too bright in the dark, which is not the case in here.

On the back you can find an RCA input, an XLR balanced input, an AC inlet and an On/Off switch. I wish it had a power button on the front panel for convenience, but it is Ok as it is.

Be warned that LD3 is not using a universal power supply, so it is either a 220V AC unit or a 110V AC unit, check the voltage on the sticker bellow the AC inlet before powering it on for the first time.

Tech Specs

In case you’ll use those XLR cables from the package and the 4-pin XLR headphone output, then LD3 will work as a fully balanced headphone amplifier from input to output. The stock gain sists at 4.5 magnification and in case you need to double it, there are two red DIP switches inside the amp. Use a tool to open the case and change the gain position. If both switches are in the ON position – that is the default gain of 4.5, put them in the Off position and you will be doubling the gain setting. However, seeing how easily it can move a pair of Audeze LCD-4 and Hifiman Arya with the default gain setting, I’m inclined to say that the stock gain is more than enough to drive all your headphones.

MKIII SE is a hybrid headphone amplifier, meaning that it will still offer some of that tube warmth and sweetness but also a lot of speed and impact a transistor-based amplifier would provide. It is a combination of the two and I’m quite curious to know if it tilts the balance towards smoothness or more so towards precision and transparency.

As for internal components, it uses an Alps-27 volume pot which is known to be super-reliable in the long run and precise at low volume positions. There are a few Philips and Wima capacitors for power filtering and coupling and the final output stage is a fully balanced, fully symmetrical, high-current and discrete transistor based. No cutting corners in here, no op-amps or capacitors in the signal path, for the purest possible signal path coming from the tube and output stage.

As for the tubes, LD3 is using two 6N11 double triodes, sadly I can’t identify the maker of these ones, I can see a star in the middle, so most probably these are soviet or Chinese tubes which are Ok, but far from the best in my opinion. There are plenty of substitutes for 6N11 tubes such as 6922, ECC88/E88CC, 6DJ8, 7308, E188CC or E288CC. Do note that in case a single tube will fail on you, you will need to change both of them with a matched pair of tubes, otherwise one tube might have higher emissions to the second one and you will be hearing a louder signal in one channel and lesser one in the other. There are tons of current production tubes from the likes of JJ, Electro-Harmonix, Ruby Tubes, TAD, Genalex, Sino, Pavane, KR and others.

If you are chasing for even more emotion in your music with sweeter harmonics, then I strongly recommend searching for some older NOS military grade tubes, especially the ones from Telefunken, Amperex, Mullard, Sylvania, RCA, Philips and Western Electric are very mid-centric and melodic sounding.

Considering that this is a hybrid headphone amp, the power rating is pretty amazing. It will offer 2500 mW in 32 Ohms and 800 mW in 300 Ohms, which should be plenty for low-sensitivity / high-current headphones as planar-magnetic but also for high impedance / high-voltage headphones as dynamic ones. Some serious power underneath that hood, so it should move and control those drivers pretty easily. Let’s check if that is really the case.

Sound Performance

I. Burn-in Requirements

Considering the number of capacitors it has inside, that big transformer on top, a fully discrete output stage and those brand-new tubes, it was clear to me that at least 48 hours of run-in will be needed to unleash its full potential. Before letting it play for two days, my curiosity couldn’t hold me still so I started listening to some tunes immediately after unpacking it.

The huge power output even at stock (low) gain position was very obvious. This unit felt considerably more powerful compared to my own Benchmark HPA4 and it felt being almost at the same level with the Flux Lab Acoustics FA-10. It didn’t make sense to me to hear such a punchy sound with the Audeze LCD-4 at only 11 to 12 o’clock volume position. After shooting back and forth few emails with the manufacturer, I understood the culprit in here. LD3 is working in the magical Class-A and that is precisely why it sounds so utterly punchy and engaging. Its case is considerably hotter compared to a lot of amps I have tried recently, including the all-tube xDuoo TA-30, it was obvious to me that it was biased working in Class-A, offering a lot of constant power, in exchange for a huge heat dissipation.

The immediate next thing I have observed was a bit of itching in the treble, that was making me uncomfortable long term. There was a hint of brightness up top with all my planar-headphones and it seems that midrange didn’t grab my soul as it usually happens with tube amplifiers. Honestly, not the perfect first impression as I was a bit underwhelmed, but I knew that a longer warm-up period will follow that should drastically change its voice.

Two days later, it just passed 50 hours of music playback, I just finished my morning coffee and I sat down listening to the same songs that I’ve listened few days ago.

Listening to Colter Wall – Sleeping on the Blacktop (Tidal / Spotify), even at the 0:21 second mark, it was clear that I was listening to something else. The drum kick felt considerably more visceral and impactful this time around, the biggest improvement though was hearing those hands clapping less taxing in the treble. The brightness tamed its temper and it was less tiring in the long run. When this cowboy started singing, his voice felt more masculine, it was going lower in its tonality, midrange felt smoother and deeper sounding too. Vocal cords vibrated longer, decaying naturally and there was simply a much bigger difference between the lowest and the highest sound intensity. Dynamics felt on a higher level too, the much sought-after midrange presence came back in full force and I started nodding my head, confirming a more natural approach to music reproduction.

I’m not sure what caused this dramatic difference, but I was simply listening to a different amplifier. The only thing that I wanted to domesticate was the wild treble response, especially somewhere around 5-to-7kHz (the most sensitive part of our hearing). I was hotter sounding in there with a slight treble emphasis, but I have a premonition that the stock tubes are causing this nasty effect. There is a chance that LD3 could sound even better well above 50 hours of burn-in, but at this point I wanted only a glass of whiskey and more music to be added to my playlist.

II. Tonality / Timbre

For starters I didn’t expect it to sound as snappy and alive, the speed that was coming from this one was something else compared to the former tube-based amplifiers I’ve tried up to this point. Hifiman Arya and Audeze LCD-4 formed a Fight Club in our headphone lab, as they are utterly responsive when it comes to those traits. If you need to check the speed and slam of an amplifier, those two did a much better job compared to the rest of the gang.

Since a big part of my audiophile diet is still rock and electronic music of all sorts and subgenres, I fired up some grunge, progressive, funk, then some drum&bass that I am very familiar with. The little fella was not far off tonality wise from its solid-state siblings siting near it on the table, with just an increase in terms of layering, spaciousness and midrange presence. I’m still a bit shocked of how well those Audeze LCD-4 are being driven by this hybrid amp and in all honesty, LD3 has more of a linear and neutral tonality with only a slight increase in the midrange and treble departments. Bass was thumping hard and hitting my ear-drums exactly as I wanted and LD3 proved that it can keep up with faster paced music no problem. Be it electronica, rock or metal, LD3 was nimble and hard punching all the time that subsequently slowly but surely raised my mood level in the mornings. There was a bit of tube bloom and warmth in there too, but not a lot of it, only just a pinch of it. It was more than enough as it improved the texture of all acoustic instruments and the weight of the voices too. Guitar plucks felt raw and metallic, violin weepings felt more natural compared to solid-state amplifiers. LD3 was indeed stealing a few traits of both solid-state and tube amps, mixing all that goodness in a simple, affordable and small package.

III. Power Output

There were plenty of amps that were driving hard loads as Audeze LCD-4 with absolute authority past 12 o’clock position. From all headphone amplifiers I’ve tried up to this point, only Flux Lab Acoustic FA-10 with its 16 Watts of power was driving them at half travel on the volume pot, with a lot of headroom left on tap. In this regard, LD3 is the second amplifier to offer such kind of power. Of course, this doesn’t tell me much as gain stage and volume rising type (exponential or linear) are also very important in all those designs. However, at 12 O’clock this LittleDot was driving the LCD-4 like it was nothing…a very pleasing experience and mind you this is only the stock gain setting. It might look small on the desk, but the power and control that is coming out of this thing is quite impressive. I would personally never change those jumpers for the high-gain, considering I still want to have the total harmonic distortion as low as possible, but for wild beasts as Hifiman HE-6, Susvara or Abyss AB-1266 users, those jumpers may be interesting to play with.

Hifiman Arya which again, are not an easy task for regular amplifiers, was already too loud at 11 O’clock position. Those huge Erzetich Phobos, Quad ERA-1 and Kennerton dynamic headphones as Magni and Gjallarhorn ware simply a child’s play for this particular amplifier. I used it in the balanced operation most of the time and only occasionally I have tried some IEM pairings on the single ended headphone jack.

Having a neutral tonality with just a splash in terms of midrange and treble, headphones like LCD-4 and Arya were more or less unchanged, with a small increase in terms of soundstage and air around those notes.

IV. Background Noise & IEM compatibility

The easiest way to test the background noise of any amplifier is to use the most sensitive headphones in your stable, raise the volume higher, close your eyes and take a listen. Before telling you how LD3 performed, I will say that all my past experiences with tube amplifiers were not that good when it came to IEM pairing. It is so happening that tube amplifiers, be them all-tube or hybrids, are not the best when it comes to THD and noise levels. Every and each of them did not really work with IEMs, including expensive design that I’ve used in the past. I was quite surprised when I connected the FiiO FA9 in the high sensitivity mode (16 Ohm and 113 dB per 1mW) and at my comfortable listening level there was just a very faint noise that I could barely hear. It was almost inaudible at about 9 o’clock which was already too loud for this amplifier.

For the record, xDuoo TA-10 and TA-30 couldn’t be used with IEMs, Audio-GD D28 and Burson Conductor 3 Reference that are costing considerably more than MKIII SE, were having a much higher noise floor and again were almost unusable with IEMs. I not sure what mumbo-jumbo and ritual dances Mr.Yu Quan Yang and his team performed, but MKIII SE could be considered dead silent with any desktop and portable headphone and very good (but not excellent) with IEMs. I did listen to a whole album with FiiO FA9 and FH7 and both started sounding jumpy and alive with a lot of dynamics kicking in. Exactly as it was the case of Flux Lab Acoustics FA-10 powering some IEMs, I felt the same kind of performance pounding my ear-drums with a much bigger force compared to any portable DAP at any price point.

I continued listening to some live records and that cleanness and dark background carried over to those songs as well. Considering how easy LD3 was untangling my music, pushing the music farther away compared to my solid-state amps, it was much easier for me to focus on the noise floor, especially in very low intensity passages.

V. Bass

I’ve experienced a controlled, deep reaching and pulsating type of bass response. It reminds me quite a lot about good sounding solid state amplifiers and I’m sure that its all-discrete transistor-based output stage left its last word exactly in here. I am not spotting longer decays or a lot of bloom as it usually happens with tube amplifiers, LD3 is nothing like that. I was actually surprised for it to keep up with the most demanding tracks of Infected Mushroom, The Prodigy and The Chemical Brothers (I’m old school, what can I do?). Even their newest albums that increased the pace were no match for the little dot. With LCD-4 and Quad ERA-1, I was able to spot 20 Hz notes, those were presented in a very raw and mean way. I’m glad to report that sub-bass was rendered with flying colors on Groove Attack (Tidal / Spotify) where my years felt like flapping in the wind, a very pleasant experience if you are into such kind of music.

Mid-bass felt exactly on the same level, it wasn’t elevated, nor over the place as it might happen with entry-level amps. LCD-4 is not a walk in the park for most amps (especially when it comes to low-end) and LD3 already proved its value with an outstanding bass performance, layering and punch. I’m serious, it’s mighty good sounding in this frequency region.

VI. Midrange

If you expect a tubey, gooey and slow midrange performance, then I’m going to disappoint you as I can’t spot anything like that. There isn’t excessive blooming or smoothing, there isn’t a roll-off at both frequency extremes. LD3 sounds a lot more like a good solid-state amplifier with a slight increase in stage and depth and if you searching for that tubey smoothness, you will not find it in here. On the other hand, it is neither dry sounding, so you can expect a really nice vocal performance. There is a big gap tonality wise between female and male voices, their pitch was rendered naturally. There is only a very small hint of sweet harmonics and naturalness. While usually listening to the latest releases of Roger Waters and Leonard Cohen, there is some kind of grain in their voices, an imperfection due to their age. With LD3 I’m hearing less grain and more smoothness, it is beatifying the overall presentation. Some might like this effect and if you would like to hear more of that, adding more bloom in here, you can change the double-triodes with something nicer. As far as I know, Little Dot US is offering much nicer tubes like Telefunken and Philips at an extra, might be worth a short if you would like more emotion and soul in your music.

VII. Treble

The very first day, LD3 was edgy sounding and had a hard treble that was difficult to swallow, it was too much at first. Things improved considerably the following days and it is no longer like that. It remained like a bad dream that I will never experience. If you just unpacked it and listened to it right away, don’t judge it too soon, it needs time to grow some cojones, just come back two days later and be surprised as I was. At this point I no longer hear those nasty trebles, but only occasionally when a brighter recording would appear on my playlist with the Hifiman Arya or Erzetich Phobos on my head (which are champions in the treble), there would be few small traces or hot treble. I know the culprit as I’ve experienced cheap tubes time and time again and please consider purchasing some NOS tubes down the road that should completely solve this issue. The older the tube, the smoother the treble should sound, I don’t know why but those double-triodes from the ’60 are truly magical sounding.
Apart from that, I find the treble extended even past octave (15kHz), I don’t hear roll-offs, it is sounding fast and it’s decaying in the same fashion. Everything else lingering up top as bells, tambourines and cymbals will have a slight increase of intensity and depending on the headphone, that could be actually a good thing.

VIII. Transient Response

This is another interesting chapter to write about. I already left few traces at the start of this article as my initial impressions were suggesting a good transient response. That is right folks, LD3 is considerably faster sounding compared to an all-tube design and it hits those ear-drums nicely too. There are many factors that are helping in achieving a nice slam in the bass and a powerful thump in the ear-drums. Class-A design is one of the reasons, a powerful and all-discrete output stage is another reason, the big transformer on top is giving a helping hand too. All of them together are offering a nice speed and impact, exactly how I like it. Even those super low 20-Ohm Quad ERA-1 and 35-Ohm Hifiman Arya are sounding alive and hard hitting. Actually, there isn’t a headphone in my stable that isn’t sounding lively and engaging on this particular amp. Even those tiny IEMs are sounding much bigger and harder slamming.

There is no point in trying a few tracks and then arriving at the same conclusion that MKIII SE is a snappy sounding amplifier with all those headphones.

IX. Soundstage & Depth

It sounds only by a hair wider and deeper compared to my own $3000 Benchmark HPA4 amplifier and considerably bigger compared to affordable solid-state amplifiers. Yes, I’m including that impressive Flux Lab Acoustics FA-10 in here too, because the small fella was pushing those notes deeper into the mix.

Compared to an all tube amplifier, LD3 was only moderately wide sounding. For example, the xDuoo TA-30 was wider sounding on all axes and that was very apparent with live albums like that of The Eagles or with any Unplugged album of any rock band. All in all, I find it having a medium to large soundstage, it is definitely not closed-in sounding, but it is neither impressively open and wide sounding too. Audio-GD D.28 and Burson Conductor 3 Reference felt as spacious and while listening to clean sounding recordings, I was able to walk-through all that music with ease and focus on a single musical instrument in a crowded track. When there are multiple voices playing on different tonalities in a song, again focusing on a single soul was easier to do and I didn’t even need to close my eyes for that to happen.

X. Detail Retrieval

Generally speaking, detail retrieval is not the strongest point of tube-based amplifiers, more like their Achilles’ Heel if you ask me, but considering that LD3 has an all discrete output stage, I can’t attribute the same words to this one. When you have a bigger and airier soundstage than usual, that is deeper sounding too, automatically all those details will be coming more naturally towards you. Transparency is at a decent to high level too and I’m pretty sure that a nicer pair of ECC88 double-triodes would further increase it. LD3 worked as a window towards my music, with little to nothing standing in its way. It was able to show all those small nuances and microdetails that were waiting to be discovered. It did leave some stones unturned compared to say a Benchmark HPA4 and Sparkos Labs Aries, but in the same time it was clearer and more transparent sounding compared to mid-range amplifiers like Erzetich Bacillus, Burson Fun / Playmate and Topping A50.

Conclusion

Overall, I liked quite a lot more its sound performance than its plain looks and bright color palette. Sound wise, it slowly but steadily grown on me. There are better sounding hybrid headphone amplifiers on the market, but I doubt there is a better one at this price point, with the same tech, Class-A bias, power output and working principle. If you ever wanted to try a tube amplifier, but could never abandon the best traits of your solid-state amp, now it’s time for a leap of faith. A hybrid amplifier is a much easier pill to swallow, as it combines the best of both worlds. LittleDot MKIII SE was an overwhelmingly powerful unit with all my headphones, it was a gentle giant with all my IEMs and quite a hard puncher too. It was decompressing my tunes with its open sounding nature, throwing a much bigger picture in front of me, which was a delight to experience with live recordings. Of course, it is still not perfect and I wish it had a tad smoother top-end and maybe a denser tone too in the midrange. Before giving my final judgement, do note that those driver tubes are having a much bigger role than you might think, exchange them with a better pair and bright treble and lean midrange could be only a distant forgotten memory.

Considering that all those positive aspects far outweighed the cons, $495 seems like a reasonable price to pay. It is an easy recommendation and I will be keeping a close eye on Little Dot and all their doings.

Little Dot MKIII SE can be bought in the US by following this link and if you are located in Europe, I recommend buying it from this web shop. I am not affiliated with either of them, so get it from your favorite store or LittleDot distributor.

PROS:

• Solid all-metal case with a pretty nice build quality
• A fully balanced and symmetrical design, input to output
• Very extended in terms of frequency response, I didn’t spot dips, only a few peaks
• A slight emphasis in the bass that makes modern music alive and engaging
• Very low noise-floor, works incredibly well with sensitive IEMs and portable headphones alike
• Really nice transparency and resolution
• Precise pin-point imaging and note placement around the listener
• Open and wide soundstage level, it is deep sounding as well
• Excellent speed and slam, incredible dynamics too
• Detailed and clean sounding most of the time
• A nice selection of inputs and outputs
• Good analog design and part selection
• A very good value in my book

CONS:

• Neutral midrange, reminiscent of solid-state electronics, a bit more soul in here would be nice
• Treble sometimes is going overboard, there is a bit more treble presence (should be solved with better drive tubes)
• Its color scheme (glossy black paint on the case, raw aluminum look on the front and golden accents on tube guards) is a bit flashy for me, a full matte silver or black would look more elegant

ASSOCIATED EQUIPMENT:

• DACs: Audiobyte HydraVox + HydraZap, Matrix Audio Element X, Denafrips Venus, Flux Lab Acoustics FCN-10, Burson Conductor 3X Performance
• DAPs: Shanling M6, FiiO M15
• Headphone Amps: Benchmark HPA4, SparkoS Labs Aries, Flux Lab Acoustics FCN-10
• Integrated Amps: KECES E40
• Power Amps: KECES S125, Kinki Studio EX-M7
• IEMs: FiiO FA9, FH7, Meze Rai Penta, Rai Solo & lots of other lower tiered ones
• Portable headphones: Sennheiser Momentum 2, Meze 99 Classics
• Wireless headphones: Sony WF-1000XM3, Sennheiser Momentum 3, Master&Dynamic MW65
• Full-sized headphones: Audeze LCD-4, Erzetich Phobos, Hifiman Arya, Quad ERA-1, Ollo S4X Reference, Kennerton Magni, Kennerton Gjallarhorn
• Loudspeakers: Buchardt S400
• Interconnects: QED Reference (x2), Aune AL3
• Speaker cables: Kimber PR8, Audioquest Type4
• Power Cables: Isotek EVO3 Premier (x3)
• Balanced Isolation Power Conditioners: PLiXiR Elite BAC400, KECES BP-600