This is a mini review for the Grado RS1i, which I had owned a few years ago, with the sources I had at that time (Melior Bitstream DAC and AMB Gamma 1), and the AMB CKKIII headphone amplifier.
The Grado RS1i, just like its RS1 predecessor, is a headphone voiced for rock music, and to be “exciting”, fun. While I have usually been suspicious about “fun” headphones (a definition often translating in “screwed up frequency response”), this one meets its goal.
The Grado RS1i pushes the upper bass and midrange forward, so to give an “on stage” feeling, and giving strength to the human voice, electric guitars, and “front instruments”. It manages to do so by staying cohesive and musical, at least for rock, metal, and also electronic music.
Its peculiar frequency response reaches its excess around 3-4 kHz, with a peak that, while adding up to the “tilt” of the music, can also make certain vocals can be excessively close (and, in sporadic cases, a bit nasal), certain electric guitars too “snarling”. This is the reason for Grado’s are said to go well with warm source/amplification, and possibly tubes.
Much portion of the treble is right, without any metallic-ness to my ears. Soundstage is pretty small but the phone also offers isolation, which is great. Imaging is very precise, also thanks to the isolation.
Sibilance is only sporadic, although the headphone is less smooth than, for example, Audio Technica AD2000. All in all, one’s system characteristics must be taken in consideration in order for the Grado RS1i not to sound too “hot”.
The bass, while lacking the lowest frequencies, is pretty hard hitting and is in tune with the forward midrange. The result is a very rhytmic, “exciting” headphone, that never misses the right timing of the music.
The soundstage is very small, both because of the physical structure of the headphone, and because of the midrange forwardness… the Grado RS1i, both because of this reason, and because of its frequency response voicing, colored to give the best with rock music, is not going to be the best choice for classical music, where its uneven color spoils the rendering of many instruments.
When well matched with a warm source (such as the analogue sounding DAC I was using at the time), the midrange peak is tamed and the resulting character helps vocals much more oftens than it spoils them, bringing to a full sounding headhphone system, bringing out the lively character of the Grado, and maximizing the sense of involvement. Conversely, the Grado RS1i will sound thin, uninvolving when fed by a digital sounding source (such as the AMB Gamma 1 I used at the time, or, just to make a reasonable guess, most Sabre based DAC’s).