The shape of IT01s shell is very similar to the original IT01, small, compact, ergonomic. It has two vents, closer to the nozzle and next to the dynamic driver. I hear absolutely no driver flex with IT01s in comparison to an occasional one with IT01 (even with the same eartips). The difference here is probably due to a new nozzle design with a removable screen (threaded) and o-ring for a better seal when you tighten the screen at the tip of the nozzle. It’s a clever idea to be able to clean and replace the nozzle screen, but also makes you wish for one of those sound filters. Maybe iBasso can consider that in the future.
The shell itself is made from an electroplated lightweight material and comes in two flavors – blue mist and smoke grey. The smoke grey version I received has a mirror reflection finish, making it more interesting as you look from different angles. Each shell has L/R marking. The nozzle is made from 304 austenitic stainless steel which has a non-magnetic property, probably a good idea since IT01s uses a very strong (high Tesla magnetic flux) driver magnet. The shell is very light, with each piece being about 8g.
While IT01 used 5um multi-layered graphene (carbon) diaphragm, IT01s steps up with a new 10mm Carbon Nanotube Dome diaphragm which is even thinner at only 3.8um. Plus, the driver uses Diamond Like Carbon (DLC) coating on the actual dome. For sure, these are all big words and at the end of the day I just care about the sound performance while treating any IEM like a black box. But it’s hard to ignore the fact of how much R&D work iBasso put into development of these new drivers, even giving them a specific name: DiNaTT Dynamic Driver – Diamond-like coating (DLC) on a domed Nanotube driver, with Tesla Magnetic Flux Technology.
I analyzed IT01s sound performance using DX200Ti w/amp8 and LGPT sources while playing a variety of my favorite test tracks, such as Agnes Obel “The curse”, Sandro Cavazza “So much better” (Avicii remix), C-Bool “Never go away”, Ed Sheeran “Shape of you”, Galantis “Hunter”, Iggy Azalea “Black widow”, Indila “Boite en argent”, Robin Schultz “Oh child”, David Elias “Vision of her”, and Michael Jackson “Dirty Diana”.
IT01s has a nicely balanced signature with a neutral natural tonality with a decent retrieval of details. Depending on pair up, in a few cases a noticed the presentation of mids being pushed slightly forward, giving vocals a little better definition or slightly back, giving the sound a mild v-shaped signature with a little more impact in low end. But overall the sound sig is relatively balanced with all frequencies being equally represented.
The soundstage is wide, with a nice depth, pushing it closer to holographic expansion depending on source pair up, suggesting that it has potentials and will scale up depending on a quality of the source. The same with layering and separation of the sounds where it can scale up/down with a source, meaning it’s never a limiting factor and will exhibit an excellent layering and separation of instruments and vocals, as well as great imaging to pin-point accurate sound position.
Bass has a nice low-end extension with a deep textured sub-bass rumble and a fast mid-bass punch, linearly tuned, not too elevated, but certainly above neutral level. Its quantity also scales up depending on the source pair up (covered in Pair Up section of the review), demonstrating how low and deep it can get when pushed harder. Also, the effect of bass quantity variation was noticeable between SPC, pure copper, and hybrid SPC/copper iBasso cable pair-ups.
Mids are neutral, with lower mids having a decent body, while upper mids being natural, detailed, not exactly micro detailed, but with plenty of clarity and resolution. In some pair ups it could get a little brighter where mids presentation was a little more forward, but it stays closer to its natural detailed tonality.
Treble has a nice controlled sparkle, never gets too bright or splashy, and don’t expect the treble extension to be too airy. Treble is well defined, but also more natural in tonality and presentation.