I’ve been loaned an IT04 some time ago, and I spent quite some audition time on it – “time flies when you’re having fun” after all doesn’t it.

This model has been released almost 4 years ago if I am not mistaken but it still holds the test of time as a very good mid-tier IEM pair, with some added uniqueness for extra measure.

At-a-glance Card

PROs	CONs
Wonderful timbre and balanced tonality.	Seriously tip-dependent.
Very good technicalities, especially imaging and layering.	Lacks a quid of vividness to sound spectacular
Good cable.	Some treble detail retrieval sacrificed to the altar of tonal coherence
Super-comfortable

Full Device Card

Test setup

Sources: Apogee Groove + Burson FUN + IEMatch / Apogee Groove + iBasso T3 / Sony NW-A55 mrWalkman / Questyle QP1R – Acoustune ET07 tips – Stock iBasso CB12s cable – lossless 16-24/44.1-192 FLAC tracks.

Signature analysis

Tonality	Timbre is bodied and musical, with well calibrated note weight all over the spectrum. Tonality is balanced with a slight warm accent, in an open-V shape presentation. The DD and the 3 BAs are kept coherent one to the others by carefully (and successfully) taming the latter to come close to the former – much the opposite of what is typically attempted on so many other multidrivers.
Sub-Bass	Fully extended, slllightly tamed under the midbass. Rumble is solid, without exaggeration.
Mid Bass	IT04 midbass is absolutely bodied, articulated and textured. While certainly not on “basshead” levels, it’s definitely bound to satisfy anyone who is looking for a moderately colored lowend, accepting some diversion from a purely neutral restitution in exchange for some well designed musicality.
Mids	Mids are very well compromised/calibrated between speed and body. Depending on tip selection (see “fit” below) they may come accross more or less forward.
Male Vocals	IT04 male vocals are clean, organic and musical, without reaching “vocal specialty” summits however
Female Vocals	Well rendered and clean, realistic, although they could be even fuller. Depending on tips selection some sibilance may come accross.
Highs	Trebles are where I reckon iBasso tuners applied their maximum focus in the IT04 case. And they suceeded in keeping them quite vivid, reasonably sparkly, and more than decently airy. Choosing different tips (see “fit”) the user can opt for a more coherent, treble-combed presentation, or a hotter trebles option.

Technicalities

Soundstage	IT04 cast a stage with good width, and very significant depth and height
Imaging	Imaging is very precise at all times
Details	Considering the 4-driver nature of the IEM, the level of microdetail IT04 delivers goes not further than an average score which is due to mid bass being is a tad too “flourished”, and presence trebles purposefully kept “under strict control”.
Instrument separation	Separation and layering is nothing short of spectacular, even on crowded passages, and even when the quite bodied subbass is involved
Driveability	Quite easy from the powering standpoint, high quality DAC seriously recommended

Physicals

Build	Housings are quite bulky but reasonably lightweight and especially shaped in a CIEM-like style offering super-easy wearability and comfort
Fit	IT04 are one of those IEMs altering their output quite significantly depeding on tip selection and fit. After the usual process, I determined that my preference goes to widebore midlength tips, namely Acoustune ET07. Subordinatedly, Symbio hybrids offer an interesting alternative, keeping bass a bit more controlled and letting mids come up with some more liberty. Symbios, however, let the bridle on the trebles loose, too loose at times, offering definitely more sparkle up to at all times, but letting occasional tonal incoherences come up depending on tracks.
Comfort	Housings have a CIEM-like “C” shape which sits nothing short of perfectly onto my outer ear granting me perfect comfort even for long sessions
Isolation	Above average per se, it’s furtherly help by the adoption of Symbio hybrids – if these are chosen on sound preference grounds
Cable	IT04 are supplied bundled with iBasso CB12s cable, featuring 8 monocrystal silver & silver plated monocrystal copper wires, modular plug termination offering free choice amongst 3.5 and 2.5 plugs. The same cable is also available separately for $99,00. Considering the product’s asking price, I consider the presence of a premium cable inside the package an obviousness; sadly this is not at all the rule for so many other manufacturers, so kudos, I guess, to iBasso for the choice.

Specifications (declared)

Housing	Contoured fit housing with carbon fiber plate and glossy smooth finish
Driver(s)	1 10mm Dynamic Graphene & 3 Knowles Balanced Armature
Connector	MMCX
Cable	iBasso CB12s – hand braided 8-wire mono crystal silver & silver plated monocrystal copper wires. Modular termination plugs. 3.5 and 2.5 plugs supplied
Sensitivity	110 dB
Impedance	16 Ω
Frequency Range	5 – 40000 Hz
Package & accessories	N/A (assessed a privately owned unit)
MSRP at this post time	$499,00

Some possibly significant quick comparisons

Tanchjim Oxygen ($ 259) is an obviously unfair comparison insofar as the Tanchjim IEM carries just 1 single DD driver for all frequencies, and is sold at a 50% lower price. That being said, Oxygen’s timbre memory has been pretty much the first to come up in my brain upon my first IT04 audition, and that’s why I jotted down some notes on the differences.

The tonality, first of all, is not the same. Both strive for neutrality but Oxygen ends up with a slight bright accented balanced tonality, IT04 with a warm-ish one. Bass is where the two IEM are extremely similar. From the mids up the situation changes pretty dramatically insofar as IT04 deliver better articulation, better accuracy, and more air while (and that’s the real point) never adding too much BA timbre on top of (or underneath if you wish) it all. IT04 is a 1+3 multidriver showing a tonal coherence pretty much equivalent to that of a good lower-tier single-DD driver, e.g. the Oxygen, while being able to extract as much BA-personality as possible from those 3 units up there.

Oriveti OH500 ($ 499). The comparison this time is between quite homogeneous alternatives: OH500 features 1 DD 4 BA while IT04 1 and 3, both drivers are sold at the very same list price. Both IEMs can be categories as “warm-balanced”, too. And, technical prowess on all the various singular aspects of the products look like just about a tie too, small differences excluded: technicalities are in both cases extremely good, and tuning shows srious competence being applied.

Simply put, their difference can be summarised as OH500 being tuned to deliver more energy, IT04 to deliver more smoothness. OH500 lets bass hit harder (if you want, maybe a little tad too loosely, depending on personal preferences), and highmids come out hotter and stronger, while IT04 pays all possible attention to keep everything as nice as possible, but as homogeneous as possible. Another not-secondary difference is driveability: OH500 is much source-pickier.

Conclusions

I liked IT04 on two different counts.

One is the more direct one: they sound very well 🙂 They carry a wonderful timbre and deliver a very pleasing, slightly warm, balanced tonality which is perfectly applicable to the acoustic music I like best.

The other is on a more abstract level: IT04 is a multidriver which is kept coherent not by trying at all cost to tune a DD as fast as possible not to sound sloppy compared to its BA companions, rather by tuning the BAs in a way as to stand their position on mutual ground vis-à-vis their companion DD’s naturally thicker body. An uncommon choice, really, and a successful one!

On the flip side I would say I’d have preferred to hear something “more” in terms of vividness and energy, and some extra effort in terms of treble detail retrieval. Perfection is not of this world, I guess.

As mentioned above, this sample was loaned to me by its private owner who paid for its out of his own pocket – this is not a review on a loaner/free unit provided by the manufacturer nor by a distributor.

This article previously already appeared here.