Optoma is a company we first became aware of years ago for their home theater projectors. In more recent years, they’ve become popular in the headphone community for their line of IEMS, DACs, and headphone amplifiers, which sport the NuForce brand. Foremost among these are the NuForce HEM, or “Hi-Res Ear Monitor” IEMs. This week we’re testing the HEM Dynamic, the entry-level model in the lineup. We find that although the HEM Dynamic sounds good, it has one fatal flaw that soured the experience.
Compared to some of the higher-end IEMs that we’ve tested, the HEM Dynamic feels entry-level. Its cable is detachable (favored by audiophiles), but it’s thin and prone to tangling.
Only an Android-style control pod is included, but its single button is clicky and works as it should. The cable has over-ear guides that are not moldable, but do retain their shape after bending. In the box are three sizes of silicone tips, two sizes of Comply soft foam tips, a shirt clip, and a nice zippered storage case. Though its plastic construction feels a little cheap, the HEM Dynamic looks good, with a clear outer housing that shows off some of its internal components. The HEM Dynamic is light and comfortable enough that it virtually disappears while being worn.
The HEM Dynamic uses a 6mm dynamic driver that is Hi-Res Certified; this means that it can produce frequencies from 20 hz to 40,000 hz — well beyond the range of human hearing. At just 16 ohms impedance, they’re easy enough to drive straight from Apple’s Lightning adapter. Though they may have a wide frequency response, with the right seal we heard a pretty substantial bass boost in the HEM Dynamic.
This headphone is definitely a fun pairing for electronic, pop, and rap music, though its low-end emphasis dulled rock and metal tracks beyond our preference. It’s a warm sound signature that can be downright boomy on the wrong track — we know this is exactly what many listeners are looking for, even if we might prefer a more balanced sound.
There was, unfortunately, one aspect of the HEM Dynamic’s design that we found very problematic. The nozzles that focus sound into the ear are made of the same slick, high-gloss plastic as the rest of the HEM Dynamic’s housings. They’re narrow and slick, with no notches to hold the ear tips in place. As a result, when we removed the HEM Dynamic from our ears, the tips would separated from the driver housing, left behind in our ear canal. Needless to say, this was not a pleasant experience. We tried to be careful when removing the HEM Dynamic from our ears, and even cleaned the nozzles to ensure that there was no skin oil causing this problem, but neither helped.
