In-Ear Fidelity

Itsfit Lab R3 & Fusion Review: A Different Perspective

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Itsfit Lab is a relatively new company in the IEMsphere, founded by the Vietnamese Kien Nguyen. They’ve initially gained their fame from their early work as an IEM resheller, and some of their more intricate designs are said to rival that of Kumitate’s Raden options.

Absolutely stunning.

Now, the R3 and Fusion that are in my hands aren’t recent acquisitions by any means; in fact, Itsfit had sent them to me around mid last year. I didn’t get to pen down my official thoughts on these two IEMs simply because I felt that there wasn’t much to say (more on that later).

Recently though, the Itsfit lineup seems to have gathered decent hype and critical acclaim, and so the requests for my review have become too much to ignore. And so without further ado: my thoughts on the R3 and the Fusion.

Disclaimer for the easily offended: these are just my opinions, audio is subjective, your mileage may vary, reviews are not meant to be taken personally etc. etc.

Itsfit R3

Product page:

MSRP: $305 (universal), $400 (custom)

Driver configuration: 3BA

The R3 is, I believe in Itsfits’ own words, their interpretation of UERM’s style of neutrality. And for the most part, they’ve accomplished their goal.

Comparison courtesy of the Graph Comparison Tool

In the above comparison, the measurements of the R3 in custom form were selected as the UERM I measured was also in custom form. The UERM exhibits its signature 10kHz spike while the R3 remains relatively subdued in this area, making the UERM sound energetic and clear while the R3 is almost dulled and lacking in dynamics in comparison.

In the non-tangibles, the UERM is noticeably more resolving than the R3 with significantly more width in its staging, while the R3s felt very PP8-ish in its presentation. Perhaps even less dynamic than the PP8 even, the R3 lacking a lot of the necessary “bite” required in instruments like electric guitars and even female vocals.

One explanation I can give for these observations is that the R3 is actually even more subdued in the upper-midrange relative to my personal neutral target, which is already a very conservative interpretation of Diffuse-Field neutrality:

Ultimately, while the R3 does have its niche, I’m not sure if it does that particularly well. It’s a little too laidback for me to use as a “palate cleanser”, while the overall technicalities are rather lacking (especially in resolution). But at any case, as a $400 custom the R3’s performance can still be considered as alright, even if my words may sound harsh and critical.

As a $350 universal though, it’s not going to be an easy recommendation for me.

Grade: B-

Itsfit Fusion

Product page:

MSRP: $950 (universal & custom)

Driver configuration: 1DD + 2BA + Magnetostatic tweeter

The Fusion is Itsfit’s newest rockstar, with almost unanimous acclaim from formal review sites and gaining a reputation as a “giant killer”. Now, going against the hivemind is never a pleasant task, but it’s far from my first rodeo anyways so this is just another Wednesday.

I’ll start with the positives to soften the inevitable blow. I had my doubts for the magnetostatic tweeter, but the Fusion has me pleasantly surprised. The treble is well extended but far from being peaky, and the quality of the treble’s transients is pretty much spot on with no weird ringing artifacts. The Fusion is able to present that last octave airiness without any difficulty but avoids sibilance very well. My only true critique of the treble would be an odd chasm just slightly past the upper midrange, which kills a lot of bite and texturing like I’ve mentioned with the R3. 

Now, the bad.

The lower midrange is a tricky region to get right, especially when one wants to emphasise it, but there are instances where it can be done well. The Vision Ears VE8 for instance, renowned for its almost-magical tonality that presents rich notes without being overbearingly heavy, or perhaps IEMs like the Fearless S8 or Elysian’s Hades V2 and Terminator V2, that balance out a significant lower-midrange hump with an equally-significant upper-midrange hump.

The Fusion is an instance that I’d consider to be a poorly done lower midrange emphasis, in which the end result is a boxy sound that softens the impact of percussion instruments, adds unwanted huskiness to female vocals and introduces a general claustrophobic sensation to the stage. The Fusion’s midrange is very odd and unnatural to me, and I struggle to find any genres that it can specialise in given its fundamental tonal shortcomings.

That’s not implying that the upper midrange is free from criticism; there is an unevenness in the higher registers that can make particular notes too intense while others too subdued, but this problem pretty much takes a back seat to the aforementioned lower midrange tuning.

At a price closing in on the dreaded kilobuck range, the Fusion struggles to be an anything-killer. But, if there were to be a silver lining in the clouds, it’s that I at least have some renewed hope for that magnetostatic tweeter.

Grade: C+

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Man Ho

2 thoughts on “Itsfit Lab R3 & Fusion Review: A Different Perspective”

  1. I spent some days with the Itsfit team back then. They said to me that the version sent to you was tuned a little bit different from their final one. I’m not familiar with that amount of bass, but the treble of Fusion is well done. The founder said that it’s the combination of BA and Magnetostatic drivers, not magnetostatic alone like we often interpret. They are looking forward to one improved R3 version and one improved version of their current fusion. Both will feature magnetostatic driver. Their custom iem version of the koi fish design is really awesome. It’s going to be on Headphonic or something… They also do reshell so you don’t have to buy R3 or Fusion to get that kind of mesmerizing art.

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