When asking non-audiophile friends and colleagues for their impressions, if any, of Westone Laboratories, I have discovered many think the firm focuses primarily on selling components and supplies for the global hearing aid industry. This isn’t too surprising since Westone got its start many years ago by building custom-moulded earpiece shells for the famous hearing aid maker Beltone. Over time, of course, Westone has grown and evolved so that today the firm concentrates its efforts in five separate – but related – areas: custom ear-mould products; audiology supply products; military earpiece products (yes, many fighter pilots and aircraft carrier crewmen wear Westones); digital, industrial, and hearing protection products; and personal and professional music earphones.
Naturally, Westone’s music products division is the one that will most interest Hi-Fi+ readers most and for a very important reason: Westone is arguably the one company most responsible for launching the entire contemporary custom-fit in-ear music monitor movement in the first place. In fact, if you ask around a bit you will find that Westone alumni are now spread throughout the CIEM industry, so that it is fair to say the company has played a huge (albeit understated) role in shaping today’s high-end personal audio marketplace. Out of sheer respect for Westone’s contributions to the field, we felt it was time to review the firm’s flagship ES-60 custom-fit in-ear monitors.
The ES-60 is the brainchild of veteran Westone engineer Karl Cartwright, who has probably forgotten more about music monitoring applications and their specific requirements than most of us will ever know. For insights into Cartwright’s design philosophy, we refer you to an interview he did with Hi-Fi+ that is published in the Hi-Fi+ Guide to Headphones, Earphones & Related Electronics (download your free copy at http://www.hifiplus.com/buyers_guides/1/). If you read the interview you may find, as we have, that Cartwright appears to live right at the intersection of Expertise Avenue and Humility Lane. In other words, he knows an awful lot about the art and science of in-ear monitor design, but he hasn’t let it go to his head (or ego), which is a refreshing combination, to say the least.
The ES-60 design is based on six balanced armature-type drivers grouped as a three-way array, with two bass drivers, two midrange drivers, and two high-frequency drivers per earpiece, all linked via a passive three-way crossover. These drivers are housed in custom-moulded, mostly acrylic earpiece shells and they deliver sound to the wearer’s ears via dual bores (or sound outlet tubes) embedded within the earpiece. Of this dual bore arrangement Westone says, “high and low frequency sound components are channelled through separate passages in the sound port and sum within your ear canal instead of the earpiece. The result is audibly more natural and provides a more convincing transition between frequency ranges.”
More so than many CIEM manufacturers, Westone consistently ‘sweats the details’ of its products, whether large or small. Hence, the firm has paid considerable attention to the signal cables supplied with the ES-60: namely, a set of proprietary, user-replaceable EPIC cables that Westone says are, “constructed of bifurcated, high-flex, ultra-low resistance tinsel wire, reinforced with a special aramid fibre, and braided for ultimate durability, acoustic transparency, and isolation from mechanical cable noise.”
Of special significance are the distinctive construction materials and techniques Westone uses for the ES-60 earpieces. Most manufacturers choose just one material for their earpieces and stick with it (e.g., acrylic, silicone, stabilised hardwoods, or other materials). Westone, however, deliberately takes a different approach, building the outer portions of its earpiece enclosures from hard, tough, and resilient cold pour acrylic material, but then making the inner portions of the earpieces – those that actually fit into the wearer’s ear canals – from a special temperature-reactive material that is solid and rigid at room temperature, but that becomes flexible as it reaches body temperature. Westone claims the benefits of this ‘Flex Canal’ technology are that the initially firm earpieces are easy to insert, while the subsequent softening process allows “increased comfort and (a superior) acoustic seal for incredible noise isolation.” See what I mean about sweating the details?
This same thoroughness carries over into the accessories provided with the ES-60. The CIEMs ship in a watertight, internally padded carry case moulded of translucent thermoplastic material in Westone’s signature signal orange colour. Within the case are found an owner’s manual, a padded microfibre cleaning cloth, a cleaning tool/brush, a small vial of Oto-Ease fluid (a gentle lubricant users can apply to their earpiece shells), a translucent orange cable-winding spool to help keep signal cables from becoming snarled inside the case, and – get this – a user renewable pod filled with desiccant material to help prevent moisture damage to the CIEMs when they are in storage. Capping things off, the ES-60 case comes with a plastic, credit card-sized user ID card that lists the owner’s name, the model and serial number of the CIEMs, and the monitor’s original production date.
About the only thing missing is a feature some of Westone’s competitors have adopted; specifically, a clearly marked label on the case stating something along these lines: “If found, please return these custom in-ear monitors to the manufacturer for a reward.” I mention this point only because, if one’s prized and expensive CIEMs ever should go missing, it would be nice to have mechanisms in place to help the errant monitors find their way back to their rightful owners.
But now, let’s focus on the thing we all care about most: the ES-60’s sound. As a way of explaining the Westone’s signature sound, let me begin by relating the gist of a conversation with Westone’s Karl Cartwright where I asked about his voicing strategies for the ES-60. He replied that, and I am paraphrasing here, he had tried to give the ES-60 the voicing characteristics he admired in some of the finest studio monitor-type loudspeakers he had heard—especially the sorts of speakers that might be used in mixing facilities, where low colouration and faithfulness to the source material is essential. I can’t say for sure, but I suspect Cartwright might have had in mind something along the lines of a fine pair of upper-tier Bowers & Wilkins Diamond-series floorstanding speakers as heard in a room with good acoustics. I say this because I see sonic parallels between the sound of B&W’s top end models and the sound of Westone’s ES-60 CIEMs.