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Sleek Audio SA6 Customisable Earphones Review

Key Specifications

  • Review Price: £139.95

One of the big problems with buying headphones, or any audio device for that matter, is while there are any number of good quality products to be had, they all have their own sound that defines them. Klipsch and Koss products are known for their bassy thump, Bose and Sennheiser for their warmth, while Shure and Etymotic Research tend to sacrifice low-end for pin-point accuracy that gives them a light and airy sound. All are good in their own right and if you try them all you’ll eventually find one that you prefer.

Unfortunately, few people have the chance to try everything before they buy so decisions have to be made based on past experience, hearsay, and reading reviews like this one. However, no matter how much you try and second guess the sound of a product, it’s nearly impossible to get a true sense of how it will feel.

It’s this conundrum that has, at least in part, led to Sleek Audio’s decision to create the SA6 customisable earphones. By using a combination of replacement parts, the user can tweak the sound to their desired timbre. If you want more bass you can replace the bass ports with more responsive ones or if you’re always striving for more treble you can also swap out the treble ports to get that extra bit of spark.

As with so many so called innovations though, on paper the idea sounds great but it’s in the execution that things can fall apart. So, without further ado, let’s see if Sleek Audio, which started off as a hearing-aid manufacturer, has revolutionised the earphone industry or just created another soon to be has been.

Just before I look at the earphones themselves, I want to call Sleek Audio out on its choice of company name. If you’re trying to enter such a highly competitive market as high-end audio, where there’s undeniably a large amount of caché attached to good looks and equally good names as there is about the actual products, you’ve surely got to be aware that Sleek Audio is going to be passed off as sounding a bit cheesy.

This is all the more pertinent considering the type of product Sleek Audio are debuting on the market with – as soon as a sceptic such as myself hears the words customisable we’re instantly put in mind of two things; compromise and dodgy gaming peripherals. Of course, this has little bearing on our final decision but I do hope someone at Sleek Audio realises the potential stumbling block it’s set for itself.

While first impressions on paper of the SA6s is somewhat mixed, in the flesh things are rather more positive. Everything comes well packaged and there are seemingly plenty of accessories to accompany the phones themselves. You get a neat carrying case, spare silicone tips, a cleaning tool, a set of replacement treble and bass ports, and as the system is also modular, an extension cable. Unfortunately, when you delve a little deeper you find that actually, as well as there being a few complete omissions, some of the accessories are a little under par.

The first of these quibbles is quite obvious in that, while there are a number of different size replacement tips, there are no alternative types of tip. So if you’re a fan of foam or single flange silicone tips, you’re going to be left wanting. That said, the default tips are very comfortable and I had no problems wearing the medium sized ones (pictured) for most of a nine hour flight and the sound isolation from them is only bettered by deeply inserted foam tips. It is rather ironic that an apparently customisable set of earphones doesn’t have choice in the most obvious department, though.

My second complaint is the carry case. It certainly looks like it should be useful but it very quickly becomes obvious this isn’t the case (no pun intended). It’s designed to carry the earphones with tips and cable attached and also has room for a spare pair each of the bass and treble ports. However, as well as the fact it is inadequate in that it only carries four out of the 12 spare bass and treble ports, it also has a peculiar cable management system.

The rubber recessed section that holds the phones flips up to reveal a cable reel arrangement underneath. However the reel is fixed to the body of the case so to wind the cable you need to either spin the whole case or wrap the cable manually. In fairness, it’s not inherently difficult but is rather overcomplicated and certainly no easier than the simple ‘wrap it round your hand and shove it in’ method used by the likes of Shure and Klipsch. That said, when packed the case is considerably more compact than either of the above.

My final complaint is something I’ve already touched on and that’s the spare port storage method. Ok, it’s forgivable that there isn’t room for all the spares in the main carrying case but the little piece of perforated cardboard is hardly a worthy backup. For a start, it doesn’t even include enough holes to carry all the spares – the ++treble ports are left rolling around the box – but even if it did I would still consider it falling short. At the very least there should be enough holes for all the ports (spares and defaults) so that replacing ports doesn’t require you to put down the spares mid-change – rummaging around under your neighbours seat looking for a tiny transparent piece of plastic after it’s been jolted from your seatback table during a bit of turbulence isn’t my idea of good mid-flight etiquette, even if said neighbour is sleeping. To my way of thinking, the ideal would be an enclosed plastic cartridge akin to the sort of thing drills bits are stored in.

Initial impressions of the audio quality are very encouraging as the single driver design gives a warm smooth sound that is very enjoyable. They lack the high-end accuracy that gives classical and acoustic music that open airiness that feels so intimate but rock and pop is dealt will brilliantly, especially as the volume is cranked up. Many reports cite the SA6s as having a flat sound – i.e. not exaggerated bass – but to my Shure accustomed ears they do sound distinctly more bass heavy. Overall, straight out of the box they remind me of the Klipsch Image set that Riyad just recently reviewed, which can now be had for about the same price as these.

Of course the straight out of the box sound is only one part of the SA6s arsenal and by switching between all the different treble and bass ports, you can get closer to the sound that you prefer. That said, the differences are not abundantly obvious particularly with regards the bass ports. The three different bass ports are supposed to span a range of 12db at the 20 hertz point, with an accompanying drop off around that frequency. Testing by listening to, surely the perfect test tune, 20Hz by Capricorn (a classical Trance tune) the differences are highlighted but overall the affect is subtle.

The difference between the various treble ports is more apparent and choosing the ++ ports really brings out the sibilants and cymbals. Personally I never actually settled on one particular setup, though, as all of them sounded decent and yet none really changed the overall quality of the tone – that is they don’t add extra thumping bass or add that aforementioned high-end clarity. Think of it as you would tweaking the performance of a car – you can stiffen the suspension and change the intercooler but nothing’s going to make your sporty hatchback into a supercar. Not to say that these earphones aren’t supercars of sorts in the first place but you get the drift.

As well as being able to customise their sound, the detachable cable of the SA6s, which measures 87cm to the split and 32cm from the split to each ear, also gives you a choice of how to wear them. Position the cable down and it drops straight down from your ears, position it up and you can loop the cable over the top and round the back of your ears. Either position is quite comfortable and switching between the two is also quick and easy. The picture we have actually shows the driver unit upside down (my fault not our photographer’s) so where the cable appears to hang below the bass port it actually sits above it. Also, the earphones are designed to be angled so that when inserted in the ear the cable actually hangs perpendicular to the ground, no matter whether you have the cable dropping straight down or looping over the ear.

Unfortunately, seemingly as a result of having so much to fiddle around with, the cable actually managed to become internally damaged during testing, to the point where the left ear completely cut-out eventually. Of course, this is where the ability to interchange nearly every aspect of the SA6 comes in particularly useful. All the components are available to buy separately for not too high a price so if any part does break you can easily replace it and, of course, while they’re still in warranty any broken parts will be replaced free of charge. Also, Sleek Audio has hinted that a wireless receiver kit is in development, which will enable you to listen to your music via the A2DP Bluetooth standard (nevermind iPhone users), and this will be compatible with the existing SA6 range.

All in all, then, the SA6 are a decent set of earphones that, if they were nearer £100, would get our recommendation, especially when you consider all the customisation available. However, with them nearing the £150 mark, things start to become a little less clear. Even ignoring you can get the Shure SE310s for £109.99, when you can get the likes of Shure’s SE420s for £160, paying £139.95 for a single driver set just doesn’t seem right. I know there are arguments for and against using single or multi-driver earphones but personally (and I know Riyad, for one, would agree with me on this) I find multi-driver earphones nearly always sound better. Also, while the Klipsch Image phones don’t have the customisation, they are lighter, more elegant, and have a similar overall sound for the same price.

Ultimately it comes down to what you want from your earphones. If you want the most accurate sound, spending an extra £20 and getting the SE420s would be a sure fire bet, whereas if you want a decent sound without the heavyweight cabling and drivers, the Klipsch Images may be your best bet. The SA6s then sit somewhere in the middle and throw in a bit of customisation to the mix, which you will either consider a pain in the proverbial or a true blessing.


Sleek Audio has created an intriguing product in the SA6 earphones. They combine the sort of sound quality we’d expect from a set of single driver earphones costing around £100 with some innovative sound customising features that push the price up a bit. The result is a set of cans that succeeds in confounding the problem they set out to solve – that of not knowing what you like until you’ve tried it – because you’re either likely to love or hate the whole customisation thing.

Trusted Score

Score in detail

  • Value 8

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