Westone ES5 Custom In-Ear Monitor

Audiophiles have professional musicians to thank for custom in-ear monitors. Originally created so that players on stage and in studios could hear themselves while delivering maximum isolation, custom in-ear monitors have become ubiquitous. Watch any program with musicians playing live and you’ll see “earwigs,” as they are often called, in the vocalist’s ears. On the popular TV show The Voice, after the contestants were reduced to twelve, each semi-finalist had his or her own pair of custom in-ears made.

Westone pioneered in-ear monitors, introducing its first hearing product in 1959. During the 1980s when the idea of in-ears monitors was pioneered, Westone designed and manufactured in-ear monitors for Etymotic, Shure (the E1 and E5) and Ultimate Ears. Since then Westone has expanded its product line to include in-ear solutions for music lovers as well as professional musicians. All Westone custom products are assembled in the U.S. at a factory in Colorado Springs, Colorado.

What’s Custom in a Custom In-Ear?
In-ear monitors require a good fit to work properly. If the seal is not complete, not only will bass response diminish drastically, but also the in-ear’s ability to attenuate outside noise will be seriously compromised. Universal-fit non-custom in-ear monitors usually come with a variety of replaceable tips from which the end-user can choose to attain a complete seal and comfortable fit. The Westone UM PRO30 ($479) universal-fit in-ear monitors, for example, come with ten different tip options.

With custom in-ear monitors, making an impression of your ear canal optimizes your eartip fit. A trained audiologist injects a flexible, fast-setting, silicone-like substance into your ears and then removes the “impressions” once the material has hardened into the shape of your ear canals. These impressions are used to make a positive form, which is then used as a mold to make your custom ear tips. Keep in mind that custom in-ears are more than fancy tips—the entire monitor is a molded form that, if done properly, fits in your ear exactly with not only a customized canal shape but also a custom earbud that will fit snugly and comfortably into the hollows of your ear.

Westone can make custom ear tips for any “universal-fit” monitor it markets. And you can, if you wish, have custom ear tips, called the Westone UM 56 “Custom Fit Adapter,” made from impressions you or your audiologist supplies. I had a set made for a pair of Westone universal-fit UM PRO30 in-ear monitors. The results were a better fit with the UM PRO30s than I could get from soft silicone, foam, or even triple-flange tips.

Although some custom in-ear monitors, such as the Ultimate Ears Personal Reference Monitors ($1999), are supplied with frequency alterations based on listener preferences, the ES5s under review were created to be reference-quality, wide-range, flat-response transducers.

Inside the ES5
The ES5 is Westone’s top-of-the-line, personal in-ear monitor. It contains five drivers (one bass, two midrange, and two upper-frequency) and three crossovers (the crossover points are kept secret).

Available in a myriad of colors, with custom finishes and graphics, the body of the ES5 is constructed of cold-pour acrylic material, which, according to Westone, “results in a thicker, more resilient and solid acoustic enclosure.” You can see the level of customization by logging onto Westone’s Web site (westoneaudio.com/index.php/products/custom-series/es5.html). You can also initiate the ordering process by activating the “Customize Now” box without actually committing to buying an ES5 until the final screen; you can even print and share your design, get feedback, and further refine it before purchasing your ES5s. For my review pair I opted for a dark-smoke body color and a bright red overlay on the right enclosure and a bright blue overlay on the left one. I like to be able to quickly identify which earbud goes in which ear, and with this color scheme I can.

While the body of the ES5 is a hard acrylic material, the tips are made of a different, softer stuff. This “temperature reactive” tip material softens as it warms up from contact with your ears, making for a more comfortable seal than a hard material. Westone calls this its “Flex canal” design.

Another Westone innovation is its “Dual Bore” sound-port design. According to Westone, “with Dual Bore technology, the high-and low-frequency sound components are individually channeled through two passages in the sound port. This allows high-and low-frequency material to sum within the ear canal, emulating the more natural phenomenon of live acoustic summation. The result is a more convincing transition between frequency ranges and is audibly more natural.”

As you would expect from a premium earphone, the cable is detachable and easily replaced. The ES5 comes with Westone’s EPIC (Earphone Precision Interface Cable) cable, which is constructed of bifurcated, high-flexibility, ultra-low-resistance tinsel wire reinforced with Aramid fiber (the stuff used in body armor). Its braided construction is less prone to kinks and tangles than more conventional headphone cables.

The ES-5 comes with its own miniature, Pelican-style, waterproof travel case. Attached to the case via a very heavy-duty cable will be a card with your name and the ES-5’s serial number. If your earphones are ever lost and the finder contacts Westone, Westone can arrange their return to you. After all, expensive in-ear monitors are virtually worthless to anyone but the person they were made for because they won’t properly fit anyone else.

Inside the case you’ll find a cleaning tool, a desiccant drying compound in a small round container, a miniature carbineer for attaching the case to something larger, a soft cleaning cloth, and a bottle of Oto-Ease. Oto-Ease is what my sound engineer friends call “ear slime.” When applied to the tips of your in-ear monitors, they slide into your ears far more easily. When I got my first pair of custom monitors I used saliva to facilitate insertion, but this stuff is much, much better.

The Sound of Five Drivers, Driving…
If I had only two words to describe the Westone ES5 in-ear monitors, they would be “full range.” I have never heard any headphone, closed or open design, or in-ear monitor that has more extended or well-defined bass response. Sure, I’ve heard headphones with more bass, such as the decidedly bass-heavy Sol Republic Tracks or Paradigm E3ms, but with the exception of the Stax electrostatic designs I’ve never heard a headphone that had this level of detail, air, dynamic power, and definition in its low frequencies.

The detail and air I heard in the bass regions extends upward into the rest of the ES5’s frequency range. This almost hyper-articulate quality makes the ES5 an ideal on-location monitor. Occasionally I’ve been faced with the problem of having to be in the same room as performers while making a recording. Obviously using loudspeakers for monitoring purposes is out of the question. That’s where reference in-ear monitors like the ES5s are ideal. About a year ago I recorded the Deadly Gentlemen (deadlygentlemen.com) at the Salina Schoolhouse, which is a classic one-room schoolhouse built in 1885. For that session I used my $999 Ultimate Ears IERM (In Ear Reference Monitor) custom in-ears, which are direct competition for the Westone ES5s. Listening to the recording through both earphones I was struck first by the ES5s superior bass extension, then by its ability to separate each musician from the others more completely than the Ultimate Ears IERM.

This is a good place to bring up the subject of imaging as it relates to headphones. First, any audiophile who thinks that headphones can’t create or retain imaging information and portray imaging specificity hasn’t listened intently to a good pair of headphones. Headphones can and do create an image, even one with dimensionality. The catch is that headphone imaging is very different from loudspeaker imaging. Instead of the soundstage appearing in front of you as with speakers, the soundstage extends between and sometimes outside of your ears. Depending on the headphone type, this imaging can vary dramatically.

Open-enclosure headphones such as the Stax Pro Lambda or the Audeze LCD-2 produce a soundstage that extends quite a bit past your ears. Sealed-enclosure headphones tend to have a smaller soundstage, yet on good sealed or in-ear earphones image specificity can be far more precise. The new Mr. Speakers Alpha Dog headphones are a fine example of a full-sized closed-ear headphone that images with remarkable specificity. But the ES5 imaging specificity is even better!

On my own two-channel recordings the ES5 in-ears allowed me to hear into the mix with very little effort. On some transducers, both speakers and headphones, you have to exert quite a bit more effort to listen deep into the mix, but with the ES5s the separation among instruments is so clear and finely delineated that it was easy to locate, lock onto, and aurally examine individual musical lines.

One particular area where the ES5 excelled was in retaining dynamic contrasts. Whether pop or classical the dynamic energy of the music came through in what I felt was a very truthful manner without artificial exaggeration or subtractive reduction. On Toy Matinee’s tune “Last Plane Out,” the gunshots had just the right amount of attack and impact. Even on my own 128x DSD recordings played back at native rate by the Resonessence Labs Herus DAC, the ES5s did a superb job of retaining the dynamic drive and excitement of the live concert event.

When comparing the midrange response of the ES5s with the Ultimate Ears IERMs I was immediately aware that the ES5 had a more matter-of-fact midrange presentation. The IERMs were ever so slightly warm in the midrange compared to the ES5s. And while the ES5s were more “honest” some listeners will undoubtedly prefer the IERM’s warmer, if slightly less harmonically accurate midrange. On harsher and poorly recorded material the IERMs will be less fatiguing, but the ES5s will give you more of the unvarnished sonic truth.

One of the primary reasons for opting for in-ear monitors is their ability to block out the outside world. The best in-ear monitors I’ve used can obtain 35dB isolation with a good seal. The ES5 come close to, but aren’t quite as good as, my isolation references, the Etymotic 4P in-ears with triple-flange tips. To test isolation and fit I take in-ears to my local torture chamber, commonly referred to as 24-Hour Fitness. At “the gym” the background noise level is high and I move around a lot, which is a great environment for testing an earphone’s isolation and fit.

Under gym conditions the ES5s did not isolate as completely as the Etymotic 4Ps, nor did they stay in place as well. Especially when I was on my side doing plank exercises the ES5 earpiece on the down side had a tendency to slip slightly and lose its seal. Also near the end of my workouts, when my ear canals were at maximum dampness, the right ES5 earpiece needed periodic readjustment to retain full contact.

The gym is also where I can test earphone-cable microphonics. Almost all headphone, earphone, and earbud cables have some degree of microphonic response. The closer the cable is to the ear-phone’s drivers and crossover the more microphonic the response can be. With the ES5 the first six inches of wire were highly microphonic; once the cable reaches the small, movable plastic cinch, the cable’s microphonics are damped substantially. Every time I moved my head or my baseball cap touched the cable where it snaked around my ears, the cable emitted audible low-frequency bumping sounds. Also as the cable slid around behind my head I could hear the rubbing as it moved. If you need an in-ear primarily for gym use, I would not recommend the ES5.

The Westone ES5s are among the most sensitive (120dB @ 1mW) earphones I’ve used. This means that they are far more likely to be able to achieve satisfying volume levels without taxing the headphone amplifier’s power-handling capabilities. But this high sensitivity also means that with many non-portable desktop or integrated headphone amplifiers designed to handle far less sensitive headphones you may hear hum, buzz, or hiss. The head-phone section in the April Music Eximus DP-1 produced a low-level hum, while the Olasonic D1 DAC produced low-level hiss. But with amplifiers made for higher-sensitivity headphones, such as the very modestly priced FIIO E-17 ($129), the sound came from a dead quiet. The Colorfly C4 and Astell&Kern AK100 also had absolutely silent backgrounds. But if you intend to use the ES5s with a desktop amplifier, try the combination out to ensure that it is quiet before committing to ownership.

Since the Westone has five drivers and three crossover regions I was concerned that its driver integration might not be as seam-less as an earphone with fewer drivers and crossovers, such as the three-driver Ultimate Ears IERM. But after many A/Bs with material that I am very familiar with I can confidently state that driver integration is not an audible issue.

The Best Custom In-Ear Monitors?
Many reviews and reviewers bandy about the word “best” as if it were some sort of absolute and irrefutable standard. But with experience we learn that best is a relative and subjective term. While the ES5 custom in-ears certainly rank as the most neutral and accurate in-ear monitor I’ve heard, they are not a universal earphone solution.

Your own personal enjoyment and overall opinion of the ES5 will be strongly affected by several factors. First and foremost will be the skill of the audiologist making your impressions. If your custom in-ear monitors do not fit well they will not work optimally and, in extreme cases, may well be so uncomfortable as to make long-term regular use impossible. Westone qualifies all the audiologists that it authorizes to make impressions. However, making impressions is part art as well as science, so some audiologists are going to make a better impression than others. If your ES5s don’t fit to your liking Westone will do everything possible to get a better fit, but don’t be alarmed if you need to send your ES5s back to Westone for some fine-tuning.

The second major contributor to sound quality through the ES5 in-ears will be your amplifier choice. Using an amplifier that was designed for high-sensitivity earphones will result in a far better experience than an amplifier created for high-impedance low-sensitivity earphones.

The final contributor to your overall satisfaction with the ES5 will be how and where you intend to use them. If the gym is the only place you use in-ear monitors, then you would be better served by other options. But if you are searching for a brutally honest reference-quality monitor for recording or intensive listening in environments where you must have no leakage into the room, the Westone ES5 has few equals.

SPECS & PRICING

Sensitivity: 120dB @ 1mW
Frequency response: 8Hz–20kHz
Impedance: 20 ohms @ 1kHz
Driver: Five balanced armature drivers with a passive three way crossover
Cable Length: 50″
Price: $950

Westone
2235 Executive Circle
Colorado Springs, CO 80906
(800) 525-5071
westone.com