In the following comparison I used the same sources and music selection as in sound analysis, while volume matching ever pair to ensure the accuracy of this test.
IT01s vs IT01 – there are improvements in soundstage expansion, width specifically, when comparing these two. Sound signature is another noticeable difference where IT01 is more v-shaped, while IT01s is more balanced in tuning. I’m hearing a more coherent balanced bass in IT01s below 200Hz, not as elevated as in IT01. The rest of the tonality is very similar, though IT01s mids do have a little more body and sounds a bit more organic. I also hear IT01s as having a better technical performance with improved layering between the sounds and a clearer separation. It’s obvious that IT01 is tuned with more bass, but even when I reduce it by about 6dB around 60Hz, IT01 tuning still doesn’t exactly match a more balanced sig of IT01s, and IT01s layering/separation of the sounds is still ahead of IT01 performance.
IT01s vs IT03 – I’m hearing IT01s to have a slightly wider soundstage with a more intimate depth, while IT03 has a more out of your head soundstage expansion which pushes mids further away. IT03 has a more V-shaped tuning with more sub-bass rumble, leaner mids, and a bit more aggressive lower treble peaks, while IT01s tuning is more balanced with a more linear bass tuning, more neutral lower mids and more organic upper mids, and more control in lower treble. In terms of technical performance, IT01s dynamic layered sound is not too far off.
IT01s vs IT04 – I know these are in a different class, but it’s hard to ignore that IT01s sounds like a scaled down version of IT04, perhaps due to some similarities in bass tuning and mids presentation. IT04 soundstage is wider, giving that IEM a more holographic soundstage, while both have a similar soundstage depth. In terms of signature, both have a similar balanced tuning, with a nice sub-bass rumble, more neutral lower mids, and organic detailed upper mids. IT04 mids are more transparent, more layered, and have a better retrieval of details, but IT01s is not too bad either, just scaled down. One noticeable difference is in treble, with IT04 having more control in lower treble, making it more natural, while IT01s is a little brighter, with higher peaks. If you had your eyes on IT04, but your budget can take you as far as IT03, I would recommend looking into IT01s.
IT01s vs Simgot EM3 – Both IEMs have a very similar soundstage expansion. In terms of tuning, it’s quite different. With EM3 being noticeably v-shaped, the bass is more elevated, lower mids noticeably more recessed, upper mids brighter and thinner, and treble is a little harsher. In comparison, IT01s tuning is more balanced and more coherent, bass has a similar quality with a more balanced quantity, lower mids are more neutral, upper mids are more natural and more layered, and lower treble of IT01s has a more controlled sparkle.
IT01s vs Oriveti New Primacy – IT01s soundstage has more width, while depth is similar with NP. NP mid-bass has more slam, while both have a similar sub-bass rumble, though IT01s bass has more control and sounds more layered. In lower mids, NP has a thicker body, while IT01s is more neutral. Upper mids are warmer, thicker in NP, while IT01s is more revealing, more transparent, more layered/separated. NP treble is also smoother and more rolled off in comparison to a brighter and crisper IT01s treble.
IT01s vs Mee Audio Pinnacle P1 – IT01s and P1 have a very similar soundstage expansion, both in width and depth. With bass, there are also similarities, where lower end is more balanced and not as much elevated. Lower mids are a touch leaner in P1, while IT01s lower mids are more neutral. Going up from there, P1 upper mids are much brighter and more revealing, while IT01s is more natural in tonality. Treble is where I hear the biggest difference where IT01s has a more controlled well-defined sparkle while P1 is elevated, spikey, and harsher. P1 treble has a lot of energy while IT01s treble has more control.
With an average sensitivity of 109dB and impedance of 16ohm, IT01s is easy to drive, but as I mentioned many times already – the performance scales ups depending on the quality of the source. I know it’s expected with many high end IEMs, but not always the case with budget monitors, creating a bottleneck in performance due to their limitations. Contrary to that, I found IT01s to scale up quite well with higher end sources.
iBasso DX200Ti w/amp8 – very wide, nearly holographic soundstage expansion. Balanced sound signature with a slightly elevated low end that has a deep sub-bass rumble, above neutral mid-bass punch, neutral lower mids with just a little extra body, natural detailed upper mids, and controlled treble sparkle. No hissing.
Lotoo Paw Gold Touch – wide soundstage expansion. Balanced sound signature with just a touch forward presentation of mids. Sub-bass rumble and mid-bass punch are linear, nicely balanced, above neutral for sure, lower mids are neutral, upper mids are natural detailed, treble is well controlled. This pair up makes IT01s a little more revealing without being harsh or loosing its natural tonality. Hiss free.
A&K SP1000 SS – wide soundstage expansion. Balanced sound signature, with a mild hint of v-shaped sig due to a little extra rumble in sub-bass and extra punch in mid-bass, with neutral naturally-revealing mids, and well controlled treble sparkle. Bass in this pair up hits a little harder. Hiss free performance.
iBasso DX120 – wide soundstage expansion. Sound sig is mostly balanced (w/setting of original sound mode and sharp roll off filter), just a little hint of a mild v-shape since I hear a slight elevation in sub-bass rumble and a little stronger mid-bass punch, natural detailed mids, and a well defined treble sparkle. It’s a good pair up, though technically not on the same level as DX200Ti or some other flagship. Also, there is some hissing when the volume is down to zero, or in a quiet passage of the song, but less noticeable at a normal playback volume.
Hiby R6 – wide soundstage expansion. Balanced sound signature with a deep velvety sub-bass rumble, hard hitting mid-bass punch, neutral lower mids, revealing detailed upper mids, and crisp treble sparkle. Here, mids are a little brighter, but never getting too harsh. Connected directly the treble is a bit too crisp as well, most likely due to high output impedance of R6. When used with iEMatch, upper mids and lower treble sounds more natural and under better control. No hissing.
Shanling M0 – wide soundstage expansion. Sound signature is more balanced, though tonality is a little more on a warmer side. Nice bass extension and punch, neutral warmer lower mids, natural organic upper mids, well controlled treble. The warmer tonality of the sound affects the technical performance here, making the sound not as layered and having less revealing retrieval of details. This is more of a smoother, warmer pair up example where the performance scaled down, relatively speaking. No hissing.
Samsung Galaxy S9 – wide soundstage expansion. Balanced sound signature with a warmer tonality, maybe even with a hint of a mild v-shape sig. Bass is linear with a nice balance between sub-bass and mid-bass, though the low end is less articulate. Mids are neutral, warm, smooth, detailed, but not as layered in this pair up. Treble is well controlled with less sparkle. This pair up reminds me of M0, nice smooth balanced natural sound with lesser technical performance. No hissing.
When I started to listen and compare IT01s to IT01, it felt like deja vu because it brought back memories of listening to a balanced tuned IT04 after switching from v-shaped IT03. But in that (IT04 vs IT03) comparison there were more design changes with a different dynamic driver and additional BA. IT01s accomplished a similar sound transformation by replacing a single original DD with an all new dynamic driver type, creating a more mature balanced tuned IEM.
But it wasn’t just the new signature which I find closer to my sound preference, but also the technical performance and the ability to scale it up with different sources which impressed me the most. Every IEM has its limitations, but IT01s surprised me how well it scales up to a higher level of sound performance when paired up with higher end flagship sources, something which many of my other “budget” IEMs can’t handle. Of course, I’m not up to date with all the latest flavor-of-the-month sub $200 IEMs, but based on what I have access to, I find IT01s performance to be quite impressive, and already starting to have a wishful thinking of IT04s with IT01s dynamic driver!