HiFiMAN RE-400 In-ear Monitor

The HiFiMAN RE-400s come with four sets of eartips, flanged and unflanged, and a rubber dongle for wrapping your headphones up safely.

The HiFiMAN RE-400s Waterline cost $99. By definition, waterline is the point where a boat meets the water. According to HiFiMAN representative Peter Hoagland, “waterline” implies these headphones are “reference for its class”. Is HiFiMAN trying to say these headphones float above the rest? Maybe.

Burnished aluminum casework houses the 8.5mm drivers. The encasements were slightly heavy and cold to touch. The small flanged eartips slipped into my ears comfortably. Thankfully, left and right channels were clearly indicated on the extending cable from each monitor.

Upon first listen, I complained, “Where’s the bass? They sound small.”

SM advised, “Give them some time.”

These in-ears require at least two weeks of break-in.

The RE-400s provided clarity and control to the music. With a forward presentation that is tuneful and tight, the RE-400s played music cleanly. They handled cymbals with rock & roll authority striking the right balance between metallicity, attack, and body. Guitars cut, drums punched, and keyboards sparkled, but the smallness remained. Rather than a big and warm sound, the RE-400s painted a refined and colorful yet two-dimensional picture of the music.

Over two weeks, the RE-400’s bass response improved from non-existent to gently extended down to 25Hz as heard using Stereophile’s Editor’s Choice CD. The sub synth on Bjork’s “Hyperballad” was full-bodied without interfering with the synthetic brushed snares and whispered vocals. On the same track, the Klipsch S4’s ($79.99) darker mix obscured Bjork’s lyrics but pushed forward a larger image with airier highs but harsher sibilants. Compared to the Klipsch S4s, the RE-400s had deeper bass and cleaner extension in both directions.

Listening back and forth between the Logitech|UE 900s ($399.99) and the HiFiMAN RE-400s, the 900s proved to be a much more musical experience. Through the 900s, I heard more space around the sounds, greater inner detail, deeper bass, a wider soundstage, and more precise microdynamics. The 900s also added richness to the midrange and body. The RE-400s did handle cymbals better, removing the slight haze I heard through the 900s, but overall, the higher priced Logitech|UE 900s give you more music.

If I had to choose between the HiFiMAN RE-400s and the slightly less expensive Klipsch S4s, I’d go with the 400s because of their cleaner and deeper extension in both the highs and the lows and greater mix clarity.

Is it reference for its class? I'm unsure. I'm going to have to keep swimming to find out, but if you want a tidy sound that emphasizes control and only have $100 to spend, the HiFiMAN RE-400s Waterline just might float your boat.