The signature

Red/black nozzles: varying degrees of an extreme V-shaped response depending on the filters used.

Gold nozzle: bassy with upper-midrange shout.

Purple nozzle: warm V-shaped sound.

Green nozzle: bright and bassless.

The final ranking will be based on my favourite setting, purple nozzle with purple filter.

The good

The midrange tonality is pretty good and is reminiscent of IEMs like the GR07 and EX800/1000. There’s a bit of the “piezo zing” that I’ve heard before in IEMs like the Radius HP-TWF41 or even the Noble Khan, which helps with putting in some snap and energy in cymbal crashes and hi-hat hits.

The semi-open nature of the R2 also helps with imaging, allowing for the stage to diffuse outward much more than the typical fully-sealed IEM. Though in essence this is more of an expected “cheat” than anything; for the trade-off of losing isolation, you’d usually gain back in soundstage size.

The bad

Where to start. Let’s begin with the worst: the absolute mess that are the green and gold nozzles.

The green nozzle seems to be built under a very basic concept: break the seal of an IEM, and you get no bass. Except this time, IMR thought it would be a good idea and that someone would like it. There are decent methods to tune a bass roll-off of course, but when the roll-off results in a resonance hump at 500Hz it’s not exactly something I’d call well-implemented.

The gold nozzle are all sorts of wrong on the other end of the spectrum; you get the massive bass response of the red/black filters but then, for whatever reason, suppress the absolutely crucial area of 2-4kHz and then a massive >15dB peak right around 6kHz. It absolutely doesn’t make sense and it sounds wrong.

I know what you’re thinking. Just don’t use the nozzles then! Why are you complaining? It is my philosophy that a manufacturer should be efficient with the usability of their product, especially one with the modularity that the R2 has. With more variables added to the user experience, you run the risk of overwhelming your customers with options since it takes the average listener a few days to go through all the combinations. And when two of your nozzle options are objectively garbage and two are almost identical, it just calls into question whether or not the R2’s modularity is truly useful or if it exists purely as a marketing gimmick.

This criticism extends to the filters as well; it would’ve made more sense to just choose three filters and be done with it, namely the blue, green, and gold filters. But by inflating this number with filters that barely differ with one other (the purple and red one in particular), the manufacturer just introduces unnecessary confusion to the average end-user (that most likely won’t have a microphone like me). Even from my perspective as a reviewer, it is absolutely frustrating to deal with and almost disappointing when I spend upwards of 10 minutes unscrewing and replacing the nozzles and filters, only to find that they sound almost exactly the same.

Back to the sound, the R2’s main weakness falls in its bass response. At full blast, it bleeds hard and there’s simply too much bass to keep it from overpowering the midrange. The best compromise to this is the purple nozzle, though it seems that the controlled roll-off results in audible distortion of everything from midbass and down. The bass notes sound very fuzzy and undefined, and the R2 struggles with rapid percussive hits. Not a good sign for an IEM that prides itself in its bass response.