Shure SRH1840 Headphone (Playback 62)

Transcendent Transparency

When Shure first entered the full-size headphone market its first efforts were all closed-back designs that offered good noise isolation and that were suitable for use in studio applications. Early on, Shure’s SRH840 caught our ears and struck us, then and now, as one of the best $199 headphones money can buy (click here to read the review). Still, it wasn’t lost on us that many of the best-sounding top-tier headphones Playback has reviewed have been open-back models, which led us to wonder if Shure would round out its product line with high-end, open-back designs of its own. The answer is “Yes,” and it has come in the form of two ambitious new models: the SRH1440 (MSRP $499/street, $399) and the SRH1840 (MSRP $875/street, $699). Playback has both on hand for review; I’ll cover the SRH1840 here, while my colleague Steven Stone will address the SRH1440 in a separate review.

Why go the open-back route? There are no hard and fast rules governing how open-back headphones will measure or perform vs. closed-back designs, but there are some threads of common wisdom that hold more than a few grains of truth.

Closed-back designs are typically heavier than their open-back counterparts and for obvious reasons provide superior noise isolation, making them ideal for studio applications where you would want to prevent noise bleed-through from external sound sources. But a design challenge involves the fact that closed-back ‘phones feature sealed driver enclosures, where the ear cups function much like the sealed boxes of an acoustic suspension-type loudspeaker. The good news is that the enclosure can help control driver movement and promote excellent bass, but the downside is that the enclosure also effectively makes the driver work harder. Common wisdom holds, then, that closed-back designs offer great noise isolation and can provide very accurate tonal balance, but will typically have a harder time delivering the transparent, free-flowing, expressive sound that many listeners crave.

Open-back designs features ear cups that provide strong, open-backed frames in which drivers are mounted in the open air, free to radiate sound forward into your ears, but also to the rear (most designers use thin, open-weave meshes or grills to protect the rear surfaces of the drive units). In most instances, open-back ‘phones are lighter than their closed-back counterparts and, not surprisingly, provide limited noise isolation capabilities.  Because drivers are mounted out in the open air, they must provide their own damping mechanisms to control unwanted driver diaphragm movements, and must also provide powerful and extended bass without relying on reinforcement from the ear cup enclosures. The payoff, though, comes in the listening, in that today’s best open-back ‘phones can and do sound remarkably open, transparent, and dynamically alive, which perhaps explain why so many of today’s top-tier, premium-priced headphones are open-back designs. Does Shure’s SRH1840 offer these same desirable sonic qualities? Let’s find out.

FEATURES

• Drivers: 40mm dynamic drivers with Neodymium magnets promise, says Shure, “smooth extended highs and accurate bass.”
• Open-back, circumaural (surrounding the ear) design said to provide, “exceptionally natural sound, wide stereo image, and increased depth of field.”
• Driver frame: The SRH1840 feature what Shure describes as a, “unique steel driver frame design (that) improves linearity, eliminates internal resonance, and ensures consistent performance at all volume levels."
• Headband frame/ear cup yokes: According to Shure, the SRH1840 offers, “Lightweight and durable dual-frame construction with aircraft-grade aluminum alloy yoke and stainless steel grilles for enhanced durability.”
• Overall design is said to be, “optimized for connection to external headphone amplification system.” Translation: Don’t drive it from your iPod; use an amp.
• Velour ear cup pads featuring “high density, slow-recovery foam for exceptional comfort.”
• Detachable (and thus user-replaceable) signal cables, featuring oxygen-free copper conductors with Kevlar-reinforced jackets.
• Very low weight: 0.59 lbs.
• Impedance:  65 Ohms
• Sensitivity: 96 dB/mW
• Frequency Response: 10Hz – 30kHz

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