My Video Review:
Last week I’ve tested some smooth, relaxing and warm sounding IEMs that could be listened to no end, but today some very bold, mean and visceral music making machines will be hitting my ear drums unmercifully. I’ve already met IKKO Audio when their OH1 hybrid IEMs landed on my table somewhere in 2019, but their newer OH10 feels like a completely different animal, even if both share the same hybrid architecture, shape and body.
When I thought that nothing can surprise me in the entry to mid-level segment, OH10 proved that fun and explosive dynamics can be had for as little as $199. We’re talking about a hybrid creation that uses a titanium coated dynamic driver that plays all-about-that-bass and a balanced armature that takes care of the brilliance and top octaves. IKKO Audio is not very well-known in cozy audiophile communities, but I want to shed some light and clarify that it’s a cool little brand that deserves our attention in full. I should apologize in advance to IKKO, as I have them for several months now, but today is the biggity big day as I will carefully explaining what makes them so interesting and unique. So, what are we waiting for? Let’s unbox them, check them out and listen to a lot of music.
Unboxing Experience
OH10 are coming in a thick cardboard box that opens up like a book. Inside it an envelope holds a service card and under it the IEMs themselves are sitting nicely surrounded by a lot of protective foam. Below them you can spot a brown eco-leather pouch that holds its detachable cable, it also shows the right way of inserting them. Under the pouch, there is another foam sheet that caries 6 pairs of silicone ear-tips. They look pretty much the same to me, there are 3 pairs of black tips and 3 pairs of grey tips, out of curiosity I will be measuring them both, maybe there is a difference between them.
The cable itself is a 1.2-meter-long OFC silver-plated cable ended with 2-pin 0.78mm sockets. It’s more than a decent cable, it’s a very flexible one and it doesn’t have any microphonics you’ll usually experience with cheap IEMs. If you need a higher quality cable or maybe a 2.5mm or 4.4mm balanced termination, IKKO is offering a better one at $59, which is stronger, uses higher purity conductors, has a lower impedance and better headphone connectors.
Build Quality & Looks
In reality, OH10 are one of the most beautiful entry-level IEMs I’ve held in my hands. Their shells are carved on a CNC machine, they used pure copper and you can actually feel the added weight it brought to the table. OH10 are slightly heavier to usual aluminum or stainless-steel IEM bodies and that adds a feeling of a higher quality and confidence in a product. I’m a flashlight junkie and the best flashlights are using copper and I’m getting the same vibe from the beautiful OH10. The added mass, lowers the vibration of the shell at higher volume, seriously reducing the overall total harmonic distortion, for a clearer and more natural sound.
As usual with high-performance IEMs, you can spot two very small holes in their bodies, one will move excessive air pressure behind its dynamic driver to the outside world, while the other will normalize the air pressure between your ear-canal and the IEMs themselves, for a more comfortable fit long term. While, they indeed are slightly heavier to usual IEMs, their perfect size and shape seriously improved comfort, I’m using them for several hours now and they still don’t bother me at all. Their body is smaller to usual multi-driver IEMs and their body is not pressing against my concha, again improving comfort in long listening sessions.
The outer nozzle is having a diameter of 5.7 mm – it’s basically the standard sized nozzle and you can easily use your growing ear-tip collection. The nozzle depth is at about 4mm in length, it’s a bit shorter, but I didn’t have issues using third-party tips as Comply, Spin-Fit and double-flange silicone tips. Those 2-pin connectors are buried deep in their copper shells and you will need to apply a higher force to detach that cable. I think that 2-pin connectors are less comfortable long-term since the cable is not spinning around how it does with MMCX connectors, but it’s a much sturdier connection that resists a much longer time period.
Tech inside IKKO OH10
OH10 is a hybrid IEM and its driving force consists of a massive 10 mm titanium coated dynamic driver that will take care of its bass and midrange section. The upper midrange and the whole treble region will be rendered by the famous Knowles 33518 balanced armature, that you can find in a lot of IEMs of today. A custom crossover will be splitting the signal in two, avoiding double amping, helping the drivers achieve their maximum potential.
OH10 has a sensitivity of 106 dB per 1mW of power and a nominal impedance of just 18 Ohms, meaning that you can drive these with pretty much anything that has a headphone jack. Obviously, dedicated audio sources as Bluetooth dongles, portable DAPs, DAC/Amps and desktop setups would further improve their performance. OH10 are also quite sensitive to source noise, so be sure to use a cleaner output for the best results.
As I’ve mentioned before, its body is carved from pure copper nuggets on a CNC machine, but since copper is a soft metal and quite a reactive one to oxidation, IKKO coated their shells with a titanium layer, preventing oxidation and accidental scratches. On the inside, its chamber is coated with platinum to enhance sound quality. Nothing is being mentioned about their magnets, about their strength, about the thickness of the titanium coated driver so I’ll just stop here and I’ll start hitting some eardrums!
Sound Performance
I. Preliminary Sound Impression
Almighty God of Thunder! Oh my…the amount of bass coming out of these things is absolutely bonkers! The last IEM I’ve tried that sounded as engaging and as hard slamming was a $730 IEM, by the name of LittleDot Cu KIS. While OH10 is not elevating the whole bass region that much, it still has the same thunderous type of bass, that is visceral, ruthless, like there is always a Drum’N’Bass party inside your head. Its low-end is very present even in tunes where you shouldn’t hear it at all, like classical or jazz. OH10 moves way more air down low to any other frequencies and you always feel it impactful and slamming like a hammer. For pure joy and giggles, for a fun listening experience, I don’t know anything that is more impressive at this price point. I have a strong feeling that IKKO went a Harman tuning, as it follows pretty much the same curve. Its low-end is elevated by a few dB, its midrange performance is quite natural and warm sounding. There is a roll-off happening in the upper midrange up to lower-treble region, that takes away some of the magic, ripping energy from female voices, making them emptier and hollower sounding, but starting with the mid-treble, everything plunges high, so you can hear all that energy without flexing your brain. OH10 are incredibly powerful when it comes to bass and treble performance, with little to nitpick about its mid-section. While I can complain a little about its technicalities, about bass overflowing some of the lower midrange, about a less than perfect transparency, I’m sure a lot of people will be loving these.
They aren’t sounding like your typical hybrid IEMs and I know that IKKO has a cheaper alternative having pretty much the same drivers, I’m about their OH1 that I’ve reviewed almost two years ago, but that one wasn’t nowhere as fun as OH10 is. Its low-end delivery is indeed overdone, easily going to Mariana Trench levels, standing out a lot more often, but man…it’s so damn exciting and smile inducing, that I can’t get enough of it. Being hybrid, you can expect a slightly faster pace compared to dynamic only IEMs, a faster decay of the notes, a higher detail retrieval and transparency, but a somewhat hotter top octave that can pose a problem for some. I will be measuring them soon and I’m curious to learn more about them.
II. Power Requirements
At 106 dB per 1mW of power, these very sensitive IEMs and really easy to drive. Not that easy to the most sensitive ones as FiiO FA9 (113 dB), but pretty close. They need a little more power compared to Kennerton Gjallarhorn desktop headphones, which is unusual but as I’ve explained previously, a smaller driver will need more power to offer back the same sound pressure level (SPL) of a bigger driver.
Power wise, start dancing around as you can drive these with pretty much everything that has a headphone jack, yep even smartphones, tablets and laptops are more than capable of cracking your eardrums. I never went more than 85% on my smartphone and could never go past 70% on a laptop. While these aren’t power hungry at all, you should use only clean sources as from my experience, OH10 can pick up source noise pretty easily, without too much flex. They worked good out of portable dongles as Shanling UP2, great out of Bluetooth DAC/Amps as Qudelix 5K and FiiO BTR5 and out of this world with portable DAC/Amps and Digital Audio Players as xDuoo XD05 BAL, FiiO Q5S TC and out of a Shanling M8.
Truth to be told, I’ve enjoyed equally well from the UP2 and 5K almost as much as from the Shanling M8, so you don’t really need the latest and the greatest to rock out and have a great time with OH10. Desktop setups worked great with them also, but OH10 aren’t scaling that much with high-end stuff, so again no point in going overkill with these small little buggers. Just use a noiseless source and amplifier and you’ll be fine.
III. Transient Response
Generally speaking, hybrid IEMs are somewhat faster to dynamic only earphones that founded the LDFC or Long-Decays Fan Club. Of course, not every hybrid is sounding the same, there can be exceptions, but OH10 together with LittleDot Cu Kis are leading the pack when it comes to bad attitude, hard slams in the bass and fast executed notes. With OH10, there is an overwhelming feeling of power down low, the air is heavier, it contains more air mass, lowest notes are more visceral and harder pounding. OH10 can’t outplay an all-armature IEM when it comes to speed and agility, but they will surely win that boxing round with its heavier punches. I’ll be honest with you; I don’t think I have experienced such kind of bass slam in a ~$200 IEM. I’ve heard something similar past 400 dollarydoos, making the OH10 one of the most affordable bass-head IEMs I know of.
Guitarmass of Infected Mushroom (Qobuz / Tidal) and Angel by Massive Attack (Qobuz / Tidal) felt almost painful at times. The beatings that I’ve felt were real, close and personal. I was cuffed behind my back and OH10 started working me from different angles. The extra oomph injected more adrenaline into my blood stream, improving my mood and well-being for the rest of the day. OH10 are indeed very vivid and colorful sounding little creatures, these are raging against linearity and could literally lift your mood quite easily. OH10 have a close to perfect transient response, a slightly higher velocity of the dynamic driver will be needed for an immaculate performance, but it’s still…very impressive in here.
It was pleasing to know that even small USB-C dongles and portable Bluetooth gizmos were able to awake subterranean bass notes in no time, OH10 were always engaging and hard smalling no matter the source, yep, I’ve heavily head-banged even out of a smartphone.
IV. Soundstage & Depth
With their stock cable on a single ended connection, OH10 have a medium sized soundstage, it is not impressively huge and wide by any means, but it isn’t claustrophobic either. Listening to intimate sounding jazz everything is pushed outside my head, almost approaching the shoulder level. Sounds were layered, airy and cleverly positioned around me. With dual-DAC portable devices that have a lower channel crosstalk, OH10 started sounding even deeper and more holographic, increasing the empty spaces between musical notes and expanding the overall picture. They scaled nicely with a better source, amplification and source material, especially when it came to soundstage and detail retrieval. In my opinion, its sound staging capabilities are more or less the same with a Meze RAI Solo that I’ve reviewed a few days ago and slightly better to lower-tiered IEMs like Moondrop Starfield, FiiO FH1S, Hifiman RE600 V2 and LittleDot Cu RAD.
Resident Human by Wheel (Qobuz / Tidal) is a fresh out of the oven album, that fully captured my attention with its atmospheric, less immediate approach to music reproduction. The track Dissipating had an exact note placement around the listener and its higher dynamic range to usual Progressive Rock of the moment really increased the immersion when I’ve closed my eyes. You get the same repetitiveness of Tool, some of the grittiness of Leprous and bass slams of Soen, all in a fresh and abstract look towards the genre. I’ve observed that even entry to mid-level IEMs were able to bring more air and push it around, bass slams felt raw yet pleasant, but the ones that sealed the deal for me where the drums and snare drum hits that sounded crisp, detailed, well organized and well-placed in the scenery.
V. Detail Retrieval & Transparency
I’ve already experienced Titanium coated dynamic drivers in IEMs and the same Knowless BA multiple times already and generally speaking, metal coated drivers are slightly more detailed and faster sounding, offering faster decays to regular cellulose or polymer drivers found in entry-level designs. OH10 were clean sounding for the most part, the upper region was clearly shining brighter with a higher focus on detail retrieval. Midrange also felt clean and undistorted, but less present in my tunes, as I needed more time to focus on those notes. The only part that felt less clean was the sub-bass, with the added punch and air down-low, it spilled over the lower midrange, making them less technical and transparent sounding.
Apart from that, OH10 appeared clearer and more detailed to the Meze RAI Solo, to the Moondrop Starfield and I really don’t have much to complain about them in here. If you keep your volume lower or equal to 90 dB, you’ll be controlling the whole bass region a lot better, resulting a clearer and less distorted output from the OH10. Yes, I’ve heard subtleties and a lot of nuances in my tunes, those were well preserved, with clean leading edges and contours, I’ve spotted mastering errors and others sounds that shouldn’t be there. OH10 scaled better with a higher quality source, the higher I went, a higher number of details started appearing on my radar. OH10 appeared even clearer to all wireless earbuds and IEMs that I’ve tested so far, including expensive Sennheiser, Apple and Sony units by a long shot.
There is no point in giving some music examples, as I will be arriving at the same conclusion that OH10 is clean, detailed and undistorted if you don’t go overboard with the volume.
VI. Frequency Response
I don’t know if it was on purpose or not, but its frequency response feels a lot like the Harman Curve, that so many IEM manufacturers are using nowadays as the gold standard when it comes to tuning. I beg to differ, Harman Curve is fun short term, several minutes later I start missing the upper midrange presence and the lost details that were sacrificed just to get this exact tuning. Nothing is wrong about it, normal people (read non-audiophiles) like it anyway.
A. Bass
OH10 and Bass are besties for life, you can’t separate them, they were made for each other, their bond is too strong and I’m yet to hear a deeper and a harder bass slam in an affordable IEM. While listening to Vicarious by Tool (Qobuz / Tidal), those bass guitar slams felt unreal, so emotional, so powerful, deep-down I knew that it is elevated by a few dB, but it was so pleasing and joyful at the same time. There was plenty of air lurking down low, but decays weren’t as fast as I like them to. When OH10 gained a lot in quantity and manliness, it lost in the quality assurance department. It isn’t the fastest, nor the cleanest bass I’ve heard and I didn’t like the most that it was spilling over the lower midrange, taking away some of the energy and presence from that region. Overall, their bass performance will deeply impress a bass-head, if you are one of them, you cannot go wrong with IKKOs.
B. Midrange
Being a hybrid, its dynamic driver still has a lot of work to do, not only landing punches left and right in the lowest octaves. I don’t know exactly if it’s the titanium coating or the crossover region, but its midrange feels less soul-grabbing to a Meze RAI Solo and Moondrop Starfield, it’s a little metallic and fake sounding, but it is far from dry or emotionless. It’s clean for the most part, the lower midrange feels linear and very present in my tunes, just the upper midrange sees a gentle slope that rolls-off the entire region by a few dB. Female voices felt less impressive, empty and hollow in several tracks, as I needed more time focusing my attention of those particular notes. EQ does improve their performance quite a bit, you can raise the whole region (500 Hz to 2 kHz) by about ~5 dB for a much better presence, for a heavier tone and for an added warmth.
C. Treble
Treble seems nice and shiny, it’s very present, it’s technical, clean and super-fast sounding. Thanks to its balanced armature, it doesn’t linger that much, there isn’t a longer ringing of the cymbals and bells, those felt immediate, punchy, yet grain and brightness free. There is indeed a higher presence in there as few regions felt elevated by several dB for an added punch, detail and sharpness. The most sensitive part of our hearing is also elevated, somewhere around 5 and 6 kHz musical notes appeared crisper and shinier. There is another rise at ~12 kHz that adds brilliance and shimmering, again improving the perception of a clean and detailed treble response. With very few tracks music appeared rather bright and harsh compared to a smoother sounding Meze RAI Solo, but it wasn’t that bothersome in the long run. The S sounds are a little accentuated and piercing, but only for a short period and only with treble intensive music.
Overall, the frequency response of OH10 resembles quite a lot the Harman target curve that works phenomenal with fast and punchy music.
VII. Measurements
When I’m measuring IEMs and headphones, I will always move to the Benchmark HPA4, as I find it extremely linear and super honest sounding. Gustard X26 PRO will be the main converter for this job and the measurement rig used was the MiniDSP E.A.R.S. calibrated with IDF (IEM Diffuse Field) compensation files. Do note that MiniDSP E.A.R.S. is not following any IEC standards, meaning that my readings can’t be used as reference measurements. I’m doing them just to get a general idea about their sound signature. I’ve measured them multiple times, as finding a perfect fit and a complete seal was quite a challenge.
Take a look at their RAW FR measurement. As you can see, their driver matching is pretty good, but not excellent. There is a deviation in the bass and a much smaller one in the upper treble. I have re-inserted them several times in the test rig and I’ve got exactly the same set of measurements, meaning that there is indeed a small deviation or about 1.5 dB in the sub-bass region.
You can also see its extremely powerful, balls-to-the-wall sub-bass performance. It’s elevated by several dB and that adds weight, bass slam and bad attitude. Lower midrange is great, starting a gentle descent, rolling-off the upper midrange that makes it less impressive with female vocals. Treble is either linear or elevated, but never recessed. The most sensitive part is elevated by 5 dB and there is a bigger rise of ~10 dB somewhere between ~11 to 12 kHz after which it starts going down.
Now, let’s check if its ear-tips are sounding any different. As you can see, the black ones are by about 0.8 dB more powerful in the bass, subjectively I cannot differentiate them, they sound the same to me. Less than 1 dB of difference is indistinguishable.
Their Total Harmonic Distortion (THD) is very impressive! It sits at just 0.159 % which is great considering their price point. Even with a stronger signal of 90 dB, it never goes past 0.5%, quite impressive!
Its spectral decay is good but not great, you can clearly see a longer vibration in the bass region, suggesting that its dynamic driver moves at a slower pace to its balanced armature. Nonetheless, it is still a fast-sounding IEM and this reading proves it.
Spectrogram is super clean and is not showing weird driver behavior. You can also see their hot zones better; the treble appears sharper and more present in some areas.
Their waterfall can be described as smooth and gentle, it is good in here, the only thing that bothers is a spike at 12 kHz. It if bothers you too, it can be tamed with a parametric EQ, or with a simple one from your software music player.
Overall, I’ve recorded a super-fun and wildly engaging sound signature, they have one of the lowest THD I’ve recorded so far, a fast driver recovery, a clean spectrogram and a smooth waterfall.
Conclusion
I’ve tested a substantial number of IEMs in the last few years and only a handful of units were fun and engaging sounding to me, but how about super-fun and extremely engaging? Oh well, only single one passed that test and it was the LittleDot Cu KIS. Not anymore, my fellow enthusiasts, as I’m adding the IKKO OH10 in the same list. There is no way you can listen to a pair without a smile on your face or without tapping your feet. The amount of positive energy and bass impact emanating from them is simply jaw-dropping. Think about Fostex TH900/909 type of bass, think about Audeze LCD-4 driven by a Class-A amplifier type of bass, think about having a portable sub-woofer powered by your smartphone…that type of bass. Sometimes it was too much, sometimes just right, but it was always delightful and irresistible with my electronic and rock tunes. I’m sure about one thing, they fully deserve their price point and a lot of people will be enjoying these with modern music.
You can get them directly from IKKO Audio right here, or can you can get them from HifiGo international web-store right here. At $199 there isn’t much to complain about and I’m putting my stamp of approval.
PROS:
- Good packaging, decent selection of accessories
- Great fit and finish
- Highly comfortable in long listening sessions
- Explosive dynamics, punchy and hard slamming all the time
- Deep and powerful sub-bass, extended treble
- Quite detailed and transparent sounding
- Decent soundstage size
- Good measurements
- Very easy to drive
- High value
CONS:
- Upper midrange lacks presence and warmth
- Slight driver mismatch
ASSOCIATED EQUIPMENT:
- DACs: Audiobyte HydraVox + HydraZap, Matrix Audio Element X, Gustard X26 PRO, Gustard X16, Flux Lab Acoustics FCN-10, xDuoo XA-10
- Headphone Amps: Benchmark HPA4, SparkoS Labs Aries, Flux Lab Acoustics FCN-10, Musician Andromeda, Burson Soloist 3X, Gustard H16, SMSL SP400
- IEMs: IKKO OH10, Meze RAI Solo, RAI Penta, FiiO FD5, FA9, FH7, LittleDot Cu KIS & many others
- Portable over-ear headphones: Sennheiser Momentum 2, Meze 99 Classics
- Full-sized headphones: Hifiman Susvara, Hifiman HE1000SE, Audeze LCD-4, Erzetich Phobos, Erzetich Mania, Quad ERA-1, Fostex TH909, Kennerton Wodan, Kennerton Magni, Vali, M12S, Ollo S4X Reference
- Power Amps: KECES S300
- Loudspeakers: KEF Reference 3
- Interconnects: QED Reference (x2), Topping TCX1 (x2)
- Speaker cables: Kimber PR8, Audioquest Type4
- Power Cables: Isotek EVO3 Premier (x3)
- Balanced Isolation Power Conditioners: PLiXiR Elite BAC400
