The IT03 is not as efficient as you might think regardless of the 8-ohm rating. 107dB is not as sensitive as some of the ultra-efficient IEMs in the market today such as the Campfire Audio range but the good news is that it is much less prone to noise and hiss and it does scale quite well in terms of dynamics and top-end control.
It does, however, need a bit of juice and weaker sources/amps tend to upset the delicate treble balance between being clean, clear, and energetic to being a little hot and unnatural sounding.
ZTE Axon 7
Top of the line smartphone for audio ($400)
Showing its average sensitivity with weaker amps, the Axon 7 is a good mobile phone sporting an AK4990EQ chip inside though the amp is just ok.
From the headphone jack (yes it has one!) I can get decent volume and excellent detail around 80% without the need to revert to their Dolby Atmos engine which makes things more vibrant and dynamic with the IT03 but also a little less natural sounding with weird staging.
On a completely neutral un-EQ’ed setting the IT03 hits pretty hard with a dark to neutral tonality, elevated mid-bass slam that’s natural but medium-paced, clean set of mids, and bright treble response.
It is pretty good but not DAP good and the odd time I found the treble just stray a little and sound a bit harsh as well as vocals having a touch of sibilance. Not as harsh as the iTouch 6th gen but cymbals and synth work did seem a bit peaky.
The IT03 for me just needs a little more juice than what the Axon 7 can provide. That being said it’s the most impressive smartphone DAC yet for detail, layering, and instrumental separation.
iTouch 6th Gen
It also has a headphone jack so right there one of life’s small blessings. The amp on the iTouch is not bad either in comparison to the Axon 7 and can easily hit pretty loud levels as low as 60% with the IT03.
Tonally it is a little softer and less detailed than what the Axon 7 can deliver with its superior DAC and also the IT03 staging feels more intimate and less well separated on the iTouch 6th Gen.
There is also a metallic edge and sharp attack to its lower to mid-treble that can give it a slightly harsh quality on percussion, synth, and some sibilance on higher-pitched vocals. On the plus side, bass is very meaty and hard-hitting. EDM lovers and bass heads will not die of want with an IT03 and the iTouch 6th gen.
This is a far more convincing match than either of the smartphone or Apple products which, to be honest, is pretty logical. It is a dedicated DAP sporting the same AKM AK4990EQ chip as the ZTE AXON but with a far superior opamp, buffer chip stage, and circuit design. It also has far better isolation and noise suppression from everyday interferences such as you get on phones and igadgets.
Efficiency wise is in the same ballpark almost as the SE846 and the Campfire Audio Jupiter at 25-30 steps in low gain. Despite its 8-ohm impedance noise and hiss were impressively low when paired with the i5 in low gain. That low sensitivity rating of 107dB starts becoming an advantage with better-powered amps.
Tonally it’s a huge step up on the ZTE and iTouch with a full-blooded and expansive soundstage, meaty but a natural-sounding bass response, clean and clear mids but it doesn’t mask that treble energy which is a characteristic more of the IT03 than the sources and amps in question.
Vocals on the IT03/i5 pairing are slightly more forward with far better detail and texture than either of the smartphones. Using the Cayin i5 you do get a strong sense that the IT03 can scale with better sources.
Shozy Alien Gold
Impressively easy to drive on the Alien requiring -1 steps from the stock volume level on boot up. Background noise was also much lower than I expected but it is present. It becomes a distraction on crappy recordings and compressed files. In general, the background was not as black as the i5 or FiiO’s X7.
Tonally the IT03/Alien pairing is a slightly laid-back bass and treble response making a tiny bit more balanced sounding than the blood and guts approach of the Cayin N5 or the FiiO X7 with the AM5.
Vocals are organic and natural sounding which is one of the traits I quite like about the Alien so I am glad the IT03 pairing doesn’t chip away at that. This pairing also doesn’t quite have the depth of the i5 pairing but has excellent width and imaging.
There are quite a lot of potential pairings with the X7 given its module system expanded to 5 modules on the market at present with a 6th on the way. Out of the 5, the AM3 is probably the best value and offers a smooth and evenly balanced tonal profile. With the IT03 volume on low gain sets around 50-55 steps unbalanced in low gain around 5 steps higher than the 110dB 28 ohms dual DDD/Quad BA UM Martian.
Tonality – Unbalanced
Of all of the mid-tier DAPs (and perhaps even the flagships), this combination was the best matchup with the IT03 for treble performance and control with lower treble sounding the most natural of the mid-tier DAPs, slightly softer than the Paw Gold and just behind the AK380. That’s a big tick in my box.
Bass performance with the AM3/IT03 pairing is pretty good but more on the tactile or neutral side meaning it doesn’t have the i5 aggression or thickness but can slam pretty good when needed. Vocals sound natural and slightly forward and have a tiny touch of sibilance but nothing distracting.
Tonality – Balanced
Huge jump in dynamics and far more vivid presentation and impressively none of that peaky treble performance in sight. The lower treble response on the X7/AM3 balanced combo was far more natural sounding, even more so than the Opus#1 balanced output which was quite good in its own right.
It still does not have that huge slamming tonality of the i5 but it’s less laid-back sounding than going unbalanced. Overall the X7/AM3 and IT03 pairing is the most versatile and smoothest matchups of the mid-tier DAPs and my favorite by far.
Another DAP that sports both a balanced and unbalanced set of jack outs. In unbalanced mode, the IT03 pairing sits comfortable around 80- 85 digital steps so slightly harder to drive than more sensitive IEMs such as the Jupiter and Andromeda which are about 20 steps lower. Impedance ratings are not everything when it comes to sensitivity and efficiency. The Opus#1 was also a noise free experience in unbalanced mode.
Tonality – Unbalanced
Tonally, in unbalanced mode, the Opus#1 still had a relatively flatter and more neutral signature with the IT03 than the i5. Bass performance on this pairing was still full sounding but not as thick as the i5’s signature low end nor as weighted. Good pace though and decent musicality. The staging was excellent on this pairing, with really good layering and separation and accurate imaging.
What I also liked about the Opus#1 pairing is the improved control it has on sibilance and that energetic treble of the IT03 that crept into some other sources. It’s still there but it’s not as sharp, sounding a little smoother than the i5 and delivered with more detail than the Alien Gold could offer.
Tonality – Balanced
Using the balanced cable with the Opus#1 was not a night and day experience and there was not a huge need to change the volume settings but there were a few subtle but important tonal differences. Firstly, balanced mode brought a slightly more dynamic presentation with slightly better depth and weight from its dynamic driver. The second welcome subtle difference was the treble response. It’s lost even more of its edge so whilst you can still hear an emphasis in that region it sounds a lot more natural. The IT03 sounds a lot more optimal to me in balanced mode with the Opus#1.
A single unbalanced output this time from the mid-fi DX80 and whilst I did not get as black a background as the top tier Paw Gold or AK380 it still felt fairly competitive, efficiency-wise, against the likes of the Opus#1 and Shozy Alien Gold. It is only really super-efficient IEMs such as the Andromeda and Se846 that show up the noise on the DX80. With the IT03 coming also from iBasso you can get you are fairly safe in that respect. Volume control is good, on low gain it is just a little higher than those aforementioned IEMs at around 10 steps higher but no requirement to hit the high gain whatsoever.
Tonally you can file the DX80 in the Opus#1 and Alien category with a pleasant smoother tonality than the ZTE Axon 7 and iPhone but not quite as punchy or deep sounding as the i5. The DX80 though does keep the top end from sounding too peaky and unnatural and closer to how the X&/AM3 combination sounded though not quite as resolving. In keeping with the DX80’s more musical character, the vocal performance is a touch thicker and ricker sounding than the Opus#1 and has decent but not total control on sibilance, much like its peers.
The IT03/AK380 pairing was perfectly noise and hiss free in unbalanced mode with an average of 80-90 digital steps (depending on the quality of the recording) on the low gain setting. In fact, it probably had the blackest background outside of the Paw Gold in this line up with the IT03.
Tonality – Unbalanced
Tonally the IT03 and AK380 pairing are more similar to the OPUS#1 and i5 flavor and considering it is using an AK4990 DAC it is no surprise the AK380 offers a musical pairing with excellent separation, a weighted low end, and absolutely spot-on detail. That treble sizzle on some of the mid-tier DAPs has largely gone with a far more natural-sounding response and just edging the X7/AM3. This pairing is particularly good with acapella with its superb black background and imaging.
Tonality – Balanced
Balanced on the AK380 is ‘meh’ to be honest. That’s not a nod to anything wrong with the IT03 but there is just not a huge difference between going balanced and unbalanced on the AK380. If anything the unbalanced mode was the more dynamic, the more vivid and engaging than the more subdued and quieter balanced output when paired with the IT03. Balanced just seems a bit lifeless in comparison.
Lotoo Paw Gold
This pairing was as noise-free as it gets with the Paw Gold having no driving issues sitting around 40-45 steps on low gain using its unbalanced output (no balanced on the Paw Gold).
The Paw Gold/IT03 edged the AK380 pairing for clarity and smoothness with a slightly more balanced offering but no less rich in texture and detail.
Bass performance was tactile rather than omnipotent with a slightly more linear performance than the AK380 but still full sounding and impactful when called upon. The vocal performance was excellent and more controlled than the likes of the X7 and the i5 with an accurate timbre and above-average instrumental separation. Lower treble was slightly brighter and hotter than the AK380 but more accurate sounding than some of the budget DAPs.
The Orion is a different proposition to the IT03 though price-wise just a little higher at $399 but personally, I put it in the same segment, that of mid-fi. The Orion has but a single BA to cover the entire frequency range and is more sensitive than the IT03 also at almost 10 digital steps lower on the X7/Am3 setup on low gain. The IT03 is will exhibit less noise and hiss on inefficient amps compared to the Orion.
Tonally the IT03 has the more powerful and fuller sounding bass response compared to the Orion. The Orion is tight, coherent but lacks slam compared to the IT03 which goes deep with plenty of rumble and sub bass menace. That single BA of the Orion can only cover so much and will always come second to the more planted and natural-sounding dynamic driver of the IT03.
The midranges on both are closer with both sounding clear and detailed with a forward vocal presence providing a more intimate feel. The IT03 though sounds the cleaner but edgier of the two with the Orion sounding slightly softer in comparison but slightly more forgiving in nature.
The IT03 has way better treble extension and space than the Orion but this should not come as a surprise since it has a single BA dedicated to treble reproduction whereas the Orion has a single BA for everything. Those who prefer something a little softer and rolled off will find the Orion treble to their taste. Those who like a more forward treble will likely opt for the IT03.
The A73 from Fidue is a single 10mm dynamic driver and a single BA design for the mids and highs. It is rated at 107dB and 20 ohms so about 2dB more sensitive than the IT03 and slightly more resistive set of drivers.
It is cheap in comparison, almost half the price but the design materials are quite plasticky and that much cheaper looking than the more premium contoured design of the IT03. The IT03 is also a much superior fit over the Fidue A73, as in miles apart with the A73 passive isolation leaking in a lot more background noise.
It’s pretty cheap in comparison to the IT03 but in terms of tonal signature both are a bit different in their presentations with the primary difference centering on the bass response. The A73 has a more elevated midbass signature with a bit more roll-off compared to the IT03 which has an elevated sub-bass performance and more controlled mid-bass. The IT03 simply sounds more powerful than the A73’s bass with a bit more kick in it and with more body. If you want a better rumble then the IT03 provides it.
Both have slightly more neutral-sounding midranges that are detailed and quick but not necessarily that meaty sounding. Vocals on the IT03 are more forward in their presentation and natural sounding than the A73 which are a bit grainier sounding.
Both have energetic and clean treble responses that come across as a little uneven and peaky producing a slight ‘zing’ and a brittle sound around 7k. More so with the A73 which sounds a little brighter overall than the IT03. Staging wise the IT03 has better depth and width than the A73.
The Primacy is also a single 8mm dynamic driver for bass performance and a dual BA for mids and highs and is priced around $40 higher than the IT03. Ratings are quite similar also at 107dB and 11 ohms for the Primacy so both have similar volume and driving needs over the majority of the sources I matched them with.
The only key differences came with the likes of the Shozy Alien which was a hissy match with the Primacy and less so with the IT03. Both have excellent fit and seals though the IT03 for me is still a class above with a custom level seal whereas the Oriveti was Westone Surefit level. If you are in the market with $300 to buy a hybrid IEM its really going to come down to the IT03 or the Primacy.
Tonally there are just enough differences between them to appeal to slightly different markets. The Primacy bass performance, like the Fidue A73, is more mid-bass focused with an elevated response and a roll-off towards the sub-bass.
The IT03 has a more powerful and elevated sub-bass making it the more powerful sounding IEM compared to the more controlled Primacy. The Primacy micro driver though is a touch faster than the IT03 and both avoid any bleed into the midrange.
The Primacy midrange performance has just a little bit more elevation and energy in the low to 1k range than the IT03 which opts instead to place more energy and presence in the upper midrange. By contrast, the Primacy has a fairly large dip from 2-5k taking a little energy out of vocal and percussion work compared to the IT03 which is more upfront and aggressive.
Both have a peaky 7k but the Primacy peak is more of a false peak generated by the 2-5k dip just ahead of it and never gets above the midrange elevation meaning it avoids sounding as bright as the IT03’s peak which is way ahead of its mids and a few dB enhanced over the bass performance.
In turn, the IT03 has a bit more extension and sparkle and doesn’t roll off as quick as the Primacy giving it an airier and more spacious feel.
Despite my reservations on the treble performance in unbalanced mode, I actually think the iBasso IT03 is an excellent performer for those who like energetic IEMs with plenty of top-end sparkle and low-end rumble. Just do not walk away thinking this is some sort of v-shaped experience because it is not.
The balanced cable does make a positive difference. The vocal staging on the IT03 is elevated and more to the intimate side and really excels with male and lower-pitched female vocals. Sparse acoustics, ambient passages, and solo vocals sound cracking on this IEM just as EDM that needs sparkle to sound accurate excel also.
Outside of the sound, the IT03 is the best sealing IEM for under $300 that I have ever tested. No universal IEM has come as close as the IT03 to a custom level of seal and fit with stock tips. If I am commuting this and a set of warm-sounding customs might be the weapons of choice. I am dying to try them out whilst flying just to see how background noise gets shut out under testing conditions.
I think iBasso has priced the IT03 competitively. You can elect to go half the price with the hybrid A73 from Fidue but as good value as the A73 is the IT03 outperforms it. The Primacy from Oriveti is the closest competitor with some similar traits but if you want energy over smooth then the IT03 will be more satisfying.