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Etymotic Research hf2 Custom Noise Isolating Earphones Review

The term noise-isolating is bandied about a lot when talking about earphones. Certainly, ‘phones from the likes of Shure and Philips do a great job of blocking out external sound thanks to the great foam tips supplied therewith. To a lesser extent the silicone tips that are a feature of just about every canalphone bundle also offer some exclusion from invasive noises. And, of course, this isolation works both ways – enabling fellow passengers in a car, train or plane to remain undisturbed by your undoubtedly impeccable taste in music.

However, as great as these a-few-sizes-should-fit-all solutions are, they never offer quite the level of exclusion you might hope for. There’s a simple reason for that: no two persons’ ear canals are quite the same. Certainly, foam tips do a decent job of trying to fill these differing shaped ear canals by expanding to fill the available space, but it’s still an imperfect solution.

Getting closer to perfection requires a simple extension of common sense: outfit your earphones with tips custom mounted to the exact shape of your own ears ensuring a flawless fit. That’s exactly what the Etymotic Research hf2 Custom earphones offer.

The idea is that by using exactly moulded tips, significantly better isolation is provided. Because there is less external interference whatever player is driving the custom-tipped ‘phones can be run at lower volume levels which means less distortion and a reduced chance of long term hearing damage.

As purchased – exclusively from the Apple store either online or at a retail location – the hf2 Customs are just a pair of normal hf2s – still £100 a pair – with a voucher in it which is redeemed with a company called Advanced Communication Solutions (ACS) which deals with the business of creating the custom moulds. At £90 adding these tips in effect doubles the price of the phones. Both Etymotic and ACS reckon that’s worthwhile.

Once you’ve decided to splash out on some custom earphones – and paid your fee to do so – it’s time to make an appointment with an audiologist to get your ear canal impressions taken. This means having those canals filled with silicone gel which is a slightly surreal experience. Especially as I arranged to have this done in a Starbucks on Baker Street and attracted more than a couple of strange looks.

Impression taken, the mouldings find their way to ACS and up to 21 days later a pair of custom tips should arrive for your hf2s. In the meantime you can use the hf2s with the standard tips which are supplied in the package.

There’s no denying that the firm-ish, clear silicone tips supplied by ACS are wonderfully comfortable. Ease of fitting depends on just how twisty your ears are, although the method should be the same for everyone – a twisting action gently screwing the earphone into the canal. Don’t worry; it’s less violent that I just made it sound.

Once you have your hf2 Custom earphones in then be prepared to really learn the meaning of awareness should you dare to venture outside. I thought navigating Piccadilly Circus was dangerous enough when I could hear the traffic and people around me but the isolation afforded by custom-fitted earphones turns the usually simple act of crossing a road into a life-risking experience.

As you might hope, this isolation does make a tangible difference to the quality of music produced by the hf2 earphones. Or, to be pedantic, seeing as the drivers inside the earphones are the same as in the standard hf2s, the perceivable quality.

As noted before, the hf2s have a very refined, almost monitor-like, quality. There’s none of the bass-heaviness found with some rival earphones, but that’s no bad thing. Instead, what’s on offer is a beautifully detailed sound which will suit the kind of listener that favours precise, uncoloured reproduction.

Vocally driven tracks such as Phantom Planet’s California or The Saturday’s Fall especially benefit from this. Backing music remains where it should be, in the background, not dominating the tracks as it can through some earphones.

Switching to Christina Milian’s Dip it Low show that the hf2s can handle a bit of pop with aplomb. Although here I think the lessened bass is more of an issue. The haunting electronic beats of Crystal Castles definitely benefit from bassier earphones and Nine Inch Nails’ Head Down lacked presence through the hf2s. A pair of SE420s, conversely, suffered from no such issues.

This disparity was fine in the standard hf2s, which were significantly cheaper than any multi-driver earphones. However, a pair of Shure SE420s can be had for less money as these hf2s and I do think they sound better, offering similar detailing to the hf2s but without the arguably ‘sterile’ bass. I don’t have a pair of SE530s to hand to test, but at around £200 – only £20 more than these custom hf2s – I can’t see them sounding anything but notably better.

That’s the price you pay for the comfort and isolation offered by custom tips. Having splashed out on a pair of SE420s myself a little over a year ago, I’m now finding myself daily in debate as to whether to use those or the custom-tipped hf2s, simply because in the environments I’m using them, I’m generally able to get more from the hf2s, despite the technical advantage of the SE420s.

The hf2s also have the benefits of the in-line remote and microphone to consider. Being able to listen to music while out and about without missing phone calls is a luxury that is, if not hard, annoying to give up. Being able to skip between tracks on my iPhone without having to pull the thing from my pocket is similarly great.


Etymotic Research’s partnership with ACS has undoubtedly created the best sounding pair of iPhone-centric earphones available to buy. Just, be prepared to pay a sizeable premium for the privilege of enjoying them.

Trusted Score

Score in detail

  • Sound Quality 9
  • Value 7

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