Headphones

If like me you enjoy the ancient notion that an engineer is someone who can make for a shilling what any fool could make for a pound, you'll share my longstanding delight at finding unpretentious, low-bling but high-achieving products which, despite modest price tags, blow away a lot of their more expensive competitors. Products which convince you that resources have been husbanded and design effort expended in pursuit of one key goal: first-class sound.

The £139 AKG K371 comes within a hair's breadth of being just such a rarity. It's as drab as could be to look at – all black and grey – and has the sort of plasticky feel we've come to expect from inexpensive headphones. But it's like the clever kid in class who hides their abilities so as not to stand out. Put the K317 over your head, note its fine isolation, plug it in and turn on the music. Only then does its worth become obvious.

Learning Curve
What prompted our review of the K371 is the fact that it's said to follow very closely the latest Harman target curve. As anyone who has followed the headphone sphere for the past seven years will well know, Harman has made a concerted and sustained effort to reinvestigate and redefine the ideal ('target') frequency response for headphones of all sorts – circumaural (over ear), like the K371, but also supra-aural (on ear) and insert types. But thus far we've seen very few headphones that closely match the latest Harman target.

The K371 does. Or rather it does below 2.5kHz. With all manner of frequency responses and tonal balances on offer from headphones, the K371 – by adhering to the Harman target – attempts to bring some order and rationality to what is a very disordered sector of the audiophile world.

Down To Age
It should be added here, though, that Harman's own research shows that headphone response preferences are somewhat dependent on the age of the listener. We older citizens tend to like less bass than the whippersnappers, and I hold my hand up to that preference. I dislike speakers with thickened textures due to LF excess or cabinet resonance, and that desire for carefully metered lower-midrange and bass carries across to headphones.

Inside each of the K371's oval capsules is a 50mm moving-coil drive unit of conventional design but with a titanium coating applied to the diaphragm to stiffen it. Exactly what the plastic substrate is AKG doesn't say. Sound isolation is claimed to be 'superior' and that is confirmed in practice – you really do get a sense that the earpads' slow-retention foam provides a good seal, and AKG's promotional material also mentions low leakage (that is, little escape of sound pressure past the pads) which should help ensure consistent low-frequency response. Having said which, like all closed-back headphones the K371 loses bass extension if the earpad seal is compromised by leakage around spectacle arms or through hair.

The K371 is generously supplied with no fewer than three cables: two straight cables of 3m and 1.2m in length, and a 3m coiled cable. All terminate at the headset in a three-pin locking connector which attaches to the left capsule, with gold-plated 3.5mm TRS mini-jacks at the source end.

Light Headed
Meanwhile, a screw-on gold-plated sleeve adapter adds compatibility with headphone preamps fitted with ¼in jack outlets. The one other supplied accessory is a grey, soft, drawstring carrying pouch. For transportation, the capsules may be rotated up into the headband, allowing the K371 to be carried in a coat pocket, or in a briefcase, handbag or man bag without taking up too much space.

If the K371 is comfortable to wear – and it is, mostly – that's principally due to the headset tipping the scales at just 257g, although the well-padded headband, soft earpads and modest head clamping force all play their part. The earpads aren't completely circumaural if you have large ears like mine but the squish and squash is not excessive. Although the cable sheath is smooth rather than braided, the capsules are quite microphonic when tapped so there is some extraneous noise if the cable rubs over clothes or furniture. If the cable catches on your collar beneath the left capsule this can transition from mildly to very annoying.

Sail Away
For the listening I used my resident Teac HA-501 headphone amplifier [HFN Apr '14], Chord Electronics Qutest DAC [HFN Nov '18] and second-generation Mac mini running Windows XP and JRiver Media Center v22. Headphone sound is dominated by tonal balance, and the K371 sounds much as you'd expect from something between its diffuse-field and Harman-corrected responses. This is the first headphone to come my way which closely follows the latest (2017) Harman target response up to 2.5kHz and I was interested to hear whether – by postponing the up-shelving of its bass output to lower in frequency than we've typically seen in headphones with LF excess – the K371 would obviate the thickening of textures which I find so annoying with many modern headphones.