It’s okay to own multiple headphones. Unless you listen to only one type of music, you will probably find that there are very few headphones that pair well with all genres of music — to us, that’s enough to justify owning multiple headphones at any given time. When considering the sound of a headphone, we try to keep in mind that there is no “best” sound signature — each headphone is tuned to target users with particular listening preferences. This week, RHA turns that all on its head with the T20i, a high-quality IEM that uniquely allows the user to adjust its sound. We think they’re excellent.
The T20i has the same level of build quality that we’ve come to expect from RHA. Injection-molded stainless steel driver housings are connected to adjustable ear guides and a hefty cable. The T20i’s Y-split and 3.5mm jack are also made of steel, with knurled details and a somewhat rare spring strain relief. We appreciate the quality of materials all around here, though we must note that the grippy cable insulation is prone to tangles.
The T20i has MFi certification — its three-button control pod will be familiar to iOS users though its buttons are a bit mushier than we’d like. Our only complaint about the T20i’s fit is its ear guides — they can be bent to fit the ear, but don’t hold their shape for very long. In our testing, the cable guides tended to stick out slightly from the back of the head and flop around during movement.
The accessories included with the T20i are top-notch. In the box is a shirt clip, semi-rigid zippered storage case, and a wide array of ear tips. Mounted to a stainless steel plate are six sizes of standard bullet-shaped tips, two sizes of double-flange tips, and two sizes of Comply foam tips. The Comply tips are spherical — a new shape, as far as we know — and provide excellent isolation, although they may slightly dampen treble response. Experimentation is encouraged here — somewhere among all these tips is likely the ideal set for isolation and comfort. We might consider RHA’s Dacamp L1 an “accessory’ to the T20i — they make a great pairing, but the T20i is sensitive enough to be driven straight from the iPhone’s Lightning adapter.
The T20i’s most important accessory, however, is a set of steampunky cylinders mounted to another steel plate: the T20i’s acoustic filters.
Like RHA’s Dacamp L1, the T20i allows users to customize its sound. Unlike the Dacamp L1’s tone controls, adjustments to the T20i’s sound are made passively, with hardware. Three filter types are included, and they’re color coded: gold for “Treble”, silver for “Reference”, and black for “Bass.” Each filter can be screwed into the T20i’s driver housings to slightly create the effect of boosted bass or heightened treble, depending on which one is used. It should be noted that these filters aren’t actually “boosting” anything — the filters contain foam that simply attenuate treble to varying degrees. We love this system — it’s easy to find headphones that emphasize bass (great for pop and hip-hop fans) or treble (great for jazz fans), but it can be difficult to find a headphone that pairs well with all genres without some compromise. The T20i’s filters make it uniquely versatile, which we think should be very appealing for those with eclectic music tastes.
The T20i uses a single dynamic driver, but with an uncommon configuration. Two voice coils control each driver (most headphones use only one); a tiny crossover splits the audio signal such that one voice coil controls treble, and the other handles the bass. This supposedly allows the T20i to have higher-precision control over the driver; though we can’t say how much, we can say that the T20i sounds very good. The “Reference” filter is, in our opinion, a sweet spot offering a balanced, detailed sound.