The Forever Earphone

“Spend hundreds on hi-fi earphones, and they had better last. But even pricey pairs get tossed around like keys. Sleek Audio already started a durability trend with detachable cords that can be replaced if broken. Now its SA7 model is the most hard-wearing overall design we’ve seen.”

 

To read the full article pick up a copy of Popular Science’s May issue or go to: Popsci.com

“For $80, you’ll honestly be hard-pressed to find a set that is built with this level of quality.”

By Darren Murph

Impression

Sleek Audio has been trumpeting its “tunable acoustics” for years now, but up until the advent of the SA1, most every set of customizable earbuds from the outfit was only in the realm of feasibility for those with a copious amount of disposable income. Beyond that, the company was one of the few utilizing Kleer’s wireless technology in order to cut the cable between your ears and your media player, but again, the lofty price tag acted as a serious barrier to entry. Enter the SA1, which serves as Sleek’s first mainstream ‘buds that fall well within the “impulse buy” region for anyone on the hunt for a mid-range set. These just started shipping a few weeks back for $79.99, and if the Siam rosewood body didn’t turn you on already, maybe the litany of ear tip choices and promise of audiophile quality in a sub-$100 package will. Hop on past the break to see how we felt about our most intimate moments with the SA1 (and the optional Kleer W-1 wireless dongle).

“A tad expensive, maybe, but these are the wireless earphones to own”

What Hi-Fi? Sound and Vision, the world’s #1 home entertainment buyer’s guide online, recently posted a review of the Sleek Audio SA6/W-1 wireless earphones, and gave it a 5 out of 5 stars review. Here’s their pullout quote on these wireless earbuds, which is just great: “A tad expensive, maybe, but these are the wireless earphones to own.” Here’s more of the review:

 The earphones are joined by a wireless receiver, which talks to a digital transmitter that can be connected to any device with a headphone output.

 The devices are paired out of the box and a choice of three in-ear buds allows us to get the fitting spot on. The sound delivered has dynamics, detail and clarity.

 Bass is a little light and they’re still a touch expensive for what’s on offer, but if you have the money and like the dongle set-up, these are the wireless ears of choice.”

 Read the review on the What Hi-Fi? Sound and Vision website >>

And just to add a little more detail, the Sleek Audio SA6 wireless earphones use Kleer wireless audio technology deliver uncompressed, CD-quality, lossless audio with a range of up to 60 feet and listening time of up to 10 hours. In addition, the Sleek Audio SA6 wireless earbuds are also capable of transmitting point to multipoint, meaning one transmitter can stream wireless music to up to four sets of Sleek Audio wireless earbuds. And these earphones are the first and only earphones that allow a listener to go from wired to wireless and back again thanks to Sleek Audio’s patented detachable cable.

“I didn’t know that they were $80, I would have guessed that they cost twice as much.”

Here’s the dilemma: you’re listening to your favorite music, and outside noises are not only bleeding in, they are making your music less clear. Most people would turn up the volume to block the unwanted noise and amplify their audio. The only problem is that in the process, they might also be causing irreparable hearing loss. Then there’s the matter of bass and treble – sometimes your left ear needs more bass and your right more treble, and that’s not exactly something you can set on an equalizer. How do you handle that?

Sleek Audio, a two year old company that was started by the father and son audiologist team Mark and Jason Krywko, may have the answer; but first a bit of background. Sleek Audio “began when Mark found himself dissatisfied with the sound signature of the dozens of different earphones he had tried over the years, so as a 30 year veteran of the audio and custom hearing aid industries, he decided to build his own.”

To read the full review click here.

“You may not have heard of Sleek Audio, but if you’re an audiophile, I hope you have. They’ve won awards for their products so far, and it’s safe to say I can hear why.  The SA6s are an amazing set of earbuds that will bring audio to your ears the way it was intended to be heard” 

First things first; if you aren’t an audiophile, you’re just going to shake your head and ask “Why!?” for the remainder of this review, and there’s nothing wrong with that. I don’t necessarily disagree with you. Being a non-audiophile is economical, but money doesn’t matter to everyone. How do you know if you’re an audiophile? Just for you, I’ve assembled a short quiz to help you find out wether or not you are an audiophile.

1. Do you like the earbuds included with your iPod?
2. Do you find yourself using the phrase “good enough” (ever)?
3. Would you rather just enjoy music than search for the ultimate audio setup with which to properly listen?
4. Would you rather spend your money on more music instead of better equipment with which to properly listen to your current music?
5. Does the thought of spending money make you less than happy?
6. Is money hard to come by, or do you have a hard time saving money for any amount of time?

If you’ve compromised (answered yes) to any of these questions, you are not an audiophile Audiophiles never compromise. Never!

To read the complete review click HERE.

 “Begone with your negative thoughts! The combination of squeaky-clean wireless and customised sound reproduction mean render the Sleeks virtually criticism-proof.”

Sleek Audio SA6 & W1 adaptor

Rating of 5 out of 5

Like Wolfgang Mozart giving Falco a good kicking for ‘Rock Me Amadeus’, wireless music systems are a battle of new school digital convenience versus crappy old school sound quality. So welcome the Sleek Audio SA6, settling inter-generational audio arguments with CD-quality Kleer wireless streaming and individually adjustable audiophile earphones.

 

The basics

The noise-isolating SA6s are in-ear headphones with modular audio components. The W1 adaptor provides a transmitter/receiver combo that works with any standard music player, streaming music at CD quality (44kHz, 16-bit).

The good

Kleer might sound like a miracle kitchen detergent (now with extra polydichromalene!) but it’s actually the best way to stream sparkling clean digital tunes without greasy interference or bacteria-laden compression. Sleek Audio’s wireless Kleer adaptor fixes to any MP3 player or (3.5mm-jacked) mobile phone, feeding the beautifully precise SA6 earphones with hiss-free harmonies. The earphones themselves are a masterpiece of miniaturisation, with an ultra wide balanced armature driver, and configurable bass ports and treble tips to personalise your listening pleasure. Sound quality is suitably dramatic thanks to enough low-end grunt to make your toes curls and top notes that are fizzier than a bottle of vintage Krug.

The bad

Begone with your negative thoughts! The combination of squeaky-clean wireless and customised sound reproduction mean render the Sleeks virtually criticism-proof. If we were to feel critical, and honestly we’re not, the WA1 adaptor does sit on your neck a bit like a cybernetic alien parasite. But in a good way.

The bottom line

Listening to Kleer audio after Bluetooth is like suddenly discovering you can speak a new language previously reserved for supermodels, Hollywood A-listers and generous master brewers. The best wire-free music experience that money (plenty of it) can (just about) buy.

  

See Full review: FiveFWD

 

“The CT6 Customs audio experience is far above any inner ear phone I have yet tried – accurate, deep, expressive and smooth whilst engaging the outer parts of my ear canal for phenomenal soundstaging. Are they worth the fairly high price of admission and long wait? Undoubtedly.”

Sleek Audio CT6 Custom IEM in Review – Perfection

Sleek Audio: Company
Sleek Audio is a father and son partnership. Since their release of the SA6 Inner Ear monitor, they have been making waves in audio circles for uniquely designed phones that excel in audio performance despite their lower cost. The Sleek Audio Custom IEM is their finest work to date and a truly audiophile product despite costing hundreds less than many of its competitors.

Sleek Audio was started by Mark and Jason Krywko, father and son respectively. It began when Mark found himself dissatisfied with the sound signature of the dozens of different earphones he had tried over the years, so as a 30 year veteran of the audio and custom hearing aid industries, he decided to build his own.

What started as a fun project turned into a three year endeavor developing a product with his son that would revolutionize the audio industry; the SA6 acoustically customizable earphone.

Mark and Jason took their extensive experience in the audio industry and vast knowledge of the ear to create a new ideology in personal audio. Rather than focus on adding multiple, larger speakers to earphones, go back to the starting point and focus on the acoustics of the ear canal and how best to  get sound from a music player to the listener’s ear in a form recording artists intended.

Sleek Audio pride themselves on offering a tailored experience to the consumer:

All of our products are designed with the individuality of every ear in mind.
Sleek Audio allows you, for the first time, to find “your audio fingerprint” without having to sacrifice anything when it comes to your music. Sharp, precise sound can come out of a small, comfortable earphone. We’ve looked at what music lovers want out of their audio experience and designed our products accordingly……incredible sound quality, comfort, and flexibility.

Sleek Audio CT6 – Truly unrivalled
In my life, I have been silly enough to own many 300$ plus earphones, all of which have been benchmarks in some area or another. My Westone UM2 was incredibly comfortable and came tethered to a nearly noiseless cable and perfectly designed headphone jack. The Shure E500 model presented me with to-die-for mids and a sleek design while Audio Technica’s CK10 provided both looks, great sound and superior construction.

Sleek’s Custom earphone, embodies nearly every plus that the aforementioned companies have brought to portable audio, but are better in many regards. Firstly, their removable coaxial cable is both soft and noise-free and features above-average strain relief. Secondly, they provide thick, deep bass and smooth treble that edges out my hitherto favourite: the tiny CK10. But above all, their custom fit ensures comfortable, fatigue-free wear. In fact, a custom earphone is so natural feeling, that it is possible to forget that they are in the ear.

Custom Earphones – Not available at your local Futureshop
Because Sleek’s custom earphones are tailored to your ear’s size, shape and sound preferences, they cannot be purchased directly from anywhere, unless you live in Sleek Audio’s neighbourhood. You will first need to have impressions of your ears taken which is normally done by a visit to an audiologist. Sleek will also recommend an audiologist in your area if you are in the United States in case you need recommendations. My impressions were taken locally by Brad Davidson of Hearsafe Canada.

The process of taking impressions is short and consists a couple of steps. Firstly, a bit of biologically safe putty must be injected into your ear behind a safety stopper. Then, after a few minutes, the putty hardens creating a virtual mould of your inner-ear. The final step in the process takes the longest. The moulds must then be sent to Sleek and after a few emails and a good, long telephone conversation about sound preferences, your Sleek Custom earphones will be lovingly created.

Note: custom earphones take a long time to create. Be prepared to wait. Also, have your impressions professionally done. DO NOT use a home impression kit as you can damage your ears.
 

Why Customs?
This is not an easy question to answer. Originally, customs were made exclusively for stage musicians who needed hearing protection from the crowd and from loud floor-standing monitors. They have been in construction for many years by different companies such as Futuresonics, Sensaphonics, Westone and Ultimate Ears – all of whom make products that start from 600$!
Recently, smaller custom manufacturers with emerging designs and markets have taken on the more established companies and created affordable alternatives for musicians and music lovers alike. Among these are Sleek, Livewires, Alien Ears, Hear Yourself and SoundCage. I have used inner earphones since 2002 and after seven years of changing flanges, losing ear pieces and the general discomfort that I sometimes experience, decided that it was worth the switch to custom monitors.

If for no other reason, the decision to purchase custom earphones can be made solely to ensure superior comfort. Because they perfectly fit your individual ear shape, custom monitors feel almost as if nothing is in the ear. That said, the hard shell does not remould as do foamies, flanges or silicon, so if you listen whilst eating or other activities when your ears may flex and move, custom phones may intermittently lose their seal.

Sleek’s Kit and Packaging
Because Sleek’s Custom is not a typical in-ear earphone, it does not come with a typical fit-kit. Rather, the earphones, a cleaning tool, detachable coaxial cable and box are the only accessories to the shipping box. To protect your investment, Sleek provide a crush and dust proof water resistant Pelican case. They take care to ensure that your investment will not suffer from either tough couriers or your own negligence as long as it stays within the Pelican case.

Unfortunately, Sleek neglected to ship a toss-pouch or hard-sided case for more portable use, however their packaging is not wasteful. There are no throwaway plastics or hard edges on which the customer may hurt herself – it is well thought-through with every effort aimed at simplicity and utility.

Take notice of the beautiful TouchMyApps logo!

Sleek CT6 Specifications – Single Balanced Armature Design

 • Frequency Response: 10Hz-20KHz
• Noise Attenuation: -35 dB
• Standard Cable: 60 inches
• Impedance: 50 ohm
• DC Resistance: 24 ohm
• Speaker Type: Ultra Wide Band Balanced Armature Driver with Custom Porting
• Sensitivity: 110 dB SPL/mW

What that means is of little importance if you are not really into your audio. If so, then just skip over this bit. Sleek’s cable is longer even than Zagg’s 1,37 cable which is a great length for portable use. Since it is light and soft, it does not impede movement.

If you care about how easy the Sleek Customs are to drive and how much hiss they will exhibit, then the above spec will help you. An impedance of 50 ohms is nearing a gold standard at which most portable audio players are let loose and able to produce deep bass and open sound stages. Even the iPhone and iPod Touch 1G will be able to sustain good, detailed bass at 50 ohms, but will still benefit from external amping.

As for soundstage, iPod and iPhone users – you are in luck. The iDevice remains to this day on top in terms of left-to-right separation even when under load. Lastly, with a sensitivity of 110b, the Sleek Customs can be driven loudly from nearly any portable and will not hiss too much with dirty sources. Phonak’s PFE are the kings when regarding the effortless rendering of a black background even with rather hissy soruces, but Sleek’s earphones are not too sensitive as to hiss with every source.

Sleek Audio’s unique Coaxial cables
Firstly, Sleek’s cable is an interchangeable creation that works on all of Sleek Audio’s high end earphones including the SA6 universal IEMs. The connection is extremely robust with no play that could damage the internal connector. I had doubts as to the reliability of this system but after owning and listening to the custom in a variety of conditions for over a month, my fears are assuaged.

Cables can be purchased in a variety of colours as well as a pioneering new wireless technology called Kleer. The Kleer option is available for 120$ and is as testified by the following reviews, lossless and definitely peerless in wireless technology and besting feeble attempts using the technologically inferior BlueTooth.

Sleek’s cable material is similar to Phonak’s cable – it is soft and non-microphonic but is less pourous and probably less susceptible to hardening and cracking. Strain relief too is well applied to both the headphone jack and the coaxial headphone ports and inspires confidence against cable breakage, but again is missing on the Y-split. The headphone jack is a right-angle construction, which protects both the iDevice and the headphone jack.

Aside from those strong points, Sleek’s cable is ‘blingy’ with shiny plastic bits around the headphone jack and the lower portion of the Y-split. Personally, I find this design to be gaudy and unfitting for a high-end earphone – rather more in tune with cheaper looking mass-market alternatives. Adding to this image, the plastic bit from the headphone jack sometimes pops off. If you have read my reviews, you will understand that I am not a fan of weak, all plastic construction – a fact which lowered my ratings for the Audeo PFE.

Sleek CT6 Housing Quality
Sleek’s Custom housing material, is made of layered acrylic which surrounds each driver unit. Since the acrylic material is hard, it is very sturdy and despite being solid and compact, when in the ear, it is incredibly comfortable.
As a true custom product much like my Marinoni Fango steel bicycle, the Sleek earphone can be chosen in a variety of colours and you can even design a custom logo for printing on the outside shell. Mine obviously, is adorned with the letters ‘tma’ in Bahaus93 font denoting TouchMyApps. I also chose differently coloured earpieces for added personality and wuffie from the audiophile crowd. Bill from Sleek Audio was very kind in walking me through colour schemes, sound preferences and any questions I had in the process of making my earphones.

Sound Quality: The Right Fit means the Right Sound
It might seem strange that I mention fit as custom monitors are made to fit perfectly to you ear, but problems occur even with custom monitors. This can stem from the initial moulding process, from packaging, from the manufacturing step or from a multitude of other reasons. Have patience – this process may take longer than you expected, but in the end, it is worthwhile. Misfits occur with every custom monitor on the market, including the ultra expensive models from Ultimate Ears, ACS, Sensaphonics, Futresonics and Westone.

I had to apply a little nail polish to the under side of my ear pieces to get a snug fit and when I finish this review, will send my customs back to Sleek for a UV hardening process to finalise the fit.

Test Music
For my listening tests, I spent most of my time with these staples of my collection:
Armin van Buuren – Trance
Paul Oakenfold – Trance
DJ Tiësto – Trance
Ice Cube – Rap
MC Solaar – Rap
Kent – Rock/Alternative
Ultima Thule – Rock/Punk
Madeleine Peyroux – Vocal
Aphex Twin – I care Because You Do – Ambient, Space

Sleek CT6 Bass: What you want
Sleek will cater to your listening preferences when making your custom monitor. You can choose from nuetral, plus or minus for both bass and treble – I chose plus on both frequencies. Thus, my Sleek customs render more treble sparkle and greater bass presence than the standard Sleek house sound.

At 50 ohms, Sleek’s product is relatively easy to drive – a side effect is that bass definition is superbly deep and defined even from a first generation Apple iPod Nano. However, Sleek’s products utilise balanced armature type transducers – this sort of driver tends to react quickly to variations in music and appears incredibly accurate. Part of the reason for this is that the drivers do not move as much air so bass is less tactile and apt to ‘bleed’ into other parts of the music.

On that note, bass presence is nothing like the astounding dynamic-driven Turbine or NE7M, however it has much better positioning within the rest of the audible spectrum. This is due to the very hard acrylic sound tube and the fact that the driver unit itself is further out from the ear. Since custom’s sound must travel further and achieve a tighter , less giving fit with the ear, slight rumbles are more noticeable to ourter portions of the ear than with units that use flanges or foamies that dampen vibrations. There is less overall bass impact, but sound vibrations which rumble along the outer ear canal help in creating a more organic and fluid bass presentation.

If you love thick bass, be sure to tell Sleek’s team so they can tailor-make the best custom for you.

Sleek Audio CT6 Mids and Treble
Many people praise Sleek’s other model, the SA6 for its forward, lush mids and smooth highs. Their custom model is no less beautiful. I cannot say whether or not the actual sound frequency extends from 10HZ to 20 KHZ as I am not a bat, but I can say that treble reaches far on these earphones. It is smooth, non-fatiguing and simply, beautiful.

For those who love vocals, the Sleek customs will impress but not to the extent that extremely mid-oriented earphones such as the UM2 or SE530 do. Instead, the mids presentation of the Sleek customs is atmospheric and lively but does not invade into genre where overly warm mids are unneeded.In particular, Madeliene Peyroux’s voice is lovely with the Sleek on any source, but not as lusty as with a warmer sounding earphone. For this reason, the setup that I have chosen is excellent for electronic and rock music and even with rap. Again, be sure to discuss with Sleek Audio’s team about how to tailor your custom to your preferences.

Sleek Audio CT6’s Soundstage: Like No Other
Where dynamic driver based inner earphones far extend to the side and back, Sleek’s custom creates a tight but extremely well-defined sound space around your the head. If you have not noticed 3D positioning in your music before, you will with customs. They best the incredibly well placed CK10 stage and violently thrash the delicate PFE amped or unamped. Again, this likely is aided by the perfect fit that customs provide as well as from the sound vibrations that interact with your ear canal through the acrylic case rather than being absorbed into rubber or foam ear tips of universal inner earphones.

In simple terms, Sleek Audio’s Custom earphones sing an eerily accurate soundstage that dances above, below and around your head-space. They are tightly defined yet awesome in spacial presentation – unlike anything I have heard in an inner earphone.

Sleek CT6 on the Go
Because of their high-quality cable which is low on microphonic noises, Sleek’s Custom monitors are divine for out-and-about listening. They are comfortable, secure and with a good fit, unperturbed by wind noises that howl on lesser designs. However, no matter how good the sound is from an acrylic case, customs probably will not provide the same amount of isolation as a dense foamy ear tip on another deep-insertion universal earphone. This can either be a boon or a point of contention for you. Personally, I find the level of noise attenuation similar to the Turbine but lower than the PFE which nearly shut out background noises when worn with foamy ear pieces.

Sleek Audio CT6 Amped
Since I am working on finishing a short but pithy review on the Nuforce Icon Mobile headphone amplifier, I have been religiously using my various earphones with and without dedicated amplifcation. I prefer not to amp earphones as my tastes rest in portability at the sacrifice of some sound quality. However, the Sleek Audio Custom earphone amps beautifully. The most noticeable change is their sound staging which pushes out vertically and horizontally even further and depending on the amp, treble and bass nature also change. The Nuforce adds some clarity to treble and greater authority to the bass.

Rather than a dedicated amplifier, I prefer to use an impedence cable that adds resistance to the line. This option is more elegant, requiring less baggage but also renders less stellar results. For its part, my 75 ohm resistor cable eliminated any hiss from my Rockboxxed iPod Nano and went a long way to quieting my extremely noisy Sony 828 walkman.

Conclusion
For the almost reasonable price of 300$ plus the dosh for an audiologist exam, you can experience unrivalled sound and comfort. The Sleek Custom audio experience is far above any inner ear phone I have yet tried – accurate, deep, expressive and smooth whilst engaging the outer parts of my ear canal for phenomenal soundstaging. Are they worth the fairly high price of admission and long wait? Undoubtedly. The cable is well constructed if gaudy with cheap plastic bits, but overall, Sleek’s presentation and packaging including strength of design is top-notch.

Finally, Sleek do not engage in marketing in the same way that many custom balanced armature companies do. Their single balanced armature provides incredible extension and body. Most companies use multiple drivers and passive crossovers or frequency limiters to ensure that an accurate sound image is still presented to the listener. Since this is likely a marketing decision more than anything else, there is no right or wrong for the consumer.

Sleek Audio’s CT6 monitor gets kissed by TouchMyApps. Please take a look at our other Headphone reviews.

Review by: Nathan Wright, a.k.a. shigzeo – see full review here

  “For your money you’re getting not only custom molded earphones, as a fair few other companies offer, but custom tuning too. It’s the latter that would see us picking Sleek Audio over the other premium headphones offered”

When we reviewed the Sleek Audio SA6 earphones last October, there was no disguising how positively we felt about the customizable in-ear monitors. So, when Sleek told us that we could expect the same and more from their custom-molded earphones, the freshly-rebranded CT6 Customs, and offered to fit us for them while at CES back in January, we couldn’t resist trying them out. It’s been a while since our SA CT6 Customs arrived; have they lived up to expectations?

We’ve had more than a few people ask where our CT6 review is, and we admit its been some time since our video unboxing (which you can also see below). What we’ve been tracking is the Customs bedding in, the single-We’ve also been using the Customs in a variety of situations, from airplanes to listening to MP3s and CDs, both at home or the office, and when out in public.

Both of Sleek’s products are special because they’re customizable, though of course they go about this in different ways. For the SA6s, you have the choice of several interchangeable bass and treble tubes which allow you to tweak the standard balance depending on your musical and sound preferences. In the case of the CT6 Customs, their unique tailoring comes from the fact that they’re individually made for a single wearer’s ears. Sleek took molds of our outer and inner ears, and from that their audio specialist Bill crafts two unique acrylic shells, inside which their signature single balanced armature drivers.

Other choices depend on whether you prefer the cable to hang down or flip back, over the top of your ear. Sleek will position the removable-cable port either high up on the CT6 or down closer to the bottom, depending on your preference. There’s also a broad array of colors and finishes, from clear through various transparent and translucent shades, to solid acrylics and even slightly glittering options. They’ll also print on a logo of your choice from an image file you send them; as you can see, we went with the SlashGear roundel.

Sleek will fettle the treble and bass of the CT6 Customs as you enjoy it – this is obviously easier if you’ve lived with the SA6s for some time, and can carry the “settings” over – but it’s a one-time decision. Still, given the relatively fiddly nature of the bass and treble tubes on the stock headphones, it’s unlikely you’d be wanting to change them all that often anyway.

Back in our Sleek Audio SA6 review, we praised the earphones’ sparkling treble, consistently warm and natural mid-range and thick, satisfying bass. Interestingly, the sound profile of the CT6 Customs is noticeably different, even though Sleek had made them to the same settings as we were used to with the SA6s.

Part of this is undoubtedly down to the longer sound tube, which extends further into your ear canal with the CT6 Customs. Sleek will make this either long, medium or short (ours fall in the middle), dependent both on your own preference and the results of your ear mold. Given the delicacy of the inner-ear, we’re pleased their team have a background in audiology to be able to advise on that.

That’s not to say the sound is disappointing; anything but. The mid-range manages to be clearer, smoother and more balanced than with the SA6s, stepping forward as a dominant frequency range rather than merely bridging the bass and treble as so often is the case. General vocals and instruments, whether the guitars of mainstream rock or the center section of an orchestra, are finely detailed. Meanwhile the treble – in our case with the “plus” tuning, so emphasized above the norm – sparkles as with the SA6s but with a new-found airiness that’s always on the right side of shrill.

The bass – which we also specified to Sleek’s “plus” setting – isn’t as grumbling as on some headphones we’ve tested, and if your preference is truly throbbing lower frequencies then the CT6s may not quite satisfy. That said, we can only comment on our own setup; talk to Sleek Audio and stress how much low-end you’d like, and they’ll probably be able to muster up some extra in-ear thumping. That’s the benefit of having not only custom earbuds but custom tuning, too. Nonetheless, the CT6s certainly aren’t a weak bass performer, and the overall impression is one of a very balanced mixture of mids, highs and lows that suit a broad range of musical styles.

Since we still had Sleek Audio’s wireless system in from our tests with the SA6s, we plugged it into the CT6s to see if we could notice any difference. Sleek’s wireless setup bypasses Bluetooth A2DP and instead uses technology by Kleer; that promises CD-quality lossless audio. The downside is that you’ll struggle to find a PMP or cellphone with a Kleer transmitter built-in, and instead have to use the supplied dongle.

For full details of the Sleek Audio Kleer wireless system, check out this review; in terms of the CT6 Customs, we could notice no difference between the cable supplied and when going wireless. Even better, the occasional habit of the Kleer receiver swinging at the back of your neck and tugging out an SA6 earbud was bypassed with the CT6 Customs, since they have such a good grip on your ears.

Durability is a tricky one to judge. The acrylic seems sturdy, though the curved inner-ear tubes make us a little more wary of dropping the CT6s into a pocket unprotected. While the hard case Sleek Audio provide is certainly impressive, it’s also not especially pocket-friendly, and we wish they’d thrown in at least a padded pouch that would cushion the earbuds during travel. Still, they’ve survived several plane journeys, knocked about while dangling from the top of a shirt, and there are no noticeable scratches or chips; even the logos are still clear and whole. We’re perhaps being over-cautious because we know that replacing the CT6s isn’t just a case of grabbing another off-the-shelf pair.

It’s their uniqueness that makes the Sleek Audio CT6 Customs less straightforward than the SA6s – or indeed any standard earphones – and which, along with the price, could put people off. Having to have impressions made requires a trip to an audiologist, and then there’s the delay in waiting for them to be crafted and delivered; none of this is easy-going in a world where we’re used to pretty much instant gratification.

Stick it out, though, and you’re rewarded with an excellent audio experience and superb fit. The SA6s did a good job of staying in our ears, but the CT6 Customs are another level of comfort and stability; these are earbuds you can jog, jump or somersault while wearing them, and you’d strangle yourself with the cable before they fell out of your ears. Invest in the Kleer wireless system and they’re even more wearable.

There’s no denying that they’re relatively expensive for earphones: $349.99 for the earphones, plus the cost – between $25 and $50, on average – of having impressions made. The Kleer wireless system is usually another $120, though buy it at the same time as the CT6 Customs and the lot comes to $449.99. For your money you’re getting not only custom molded earphones, as a fair few other companies offer, but custom tuning too. It’s the latter that would see us picking Sleek Audio over the other premium headphones offered; at $100 over the standard SA6s it’s a small price to pay for unique fit and sound.

Review By: Chris Davies, Slashgear, Full review with unboxing video can be found here.

“You might think comparing the SA6s to a reference quality loudspeaker is a bit unfair or is designed to point out their shortcomings but that isn’t the point. The point is to determine where they fall on the scale between poor quality and reference quality sound. And the fact that they performed so well is a testament to the engineering and concern for sound quality that went into these earphones.” – Adam Goldfine, Positive Feedback Online, Issue 37

Adam Goldfine of Positive Feedback, “a Creative Forum for the Audio Arts,” has extensive experience working with and reviewing the world’s best loudspeakers, however, he took the time to dive into the world of earphones by examining Sleek Audio’s SA6’s. The full review, which takes a unique look at the earphone category by comparing high-end loudspeaker sound quality to high-end earphone sound quality can be read here:  http://www.positive-feedback.com/Issue37/sleek_sa6.htm

Review of Sleek Audio Custom Earphones

Sleek-Audio made a remarkable entry into the world of in-ears almost a year ago with the successful launch of their SA6 customizable earphones. Today I have the pleasure of putting their first custom earphones through its paces. Based upon the same principles as the SA6 the user decides the frequency response. However, unlike the SA6 you cannot change the sound signature after they are produced. In the ordering process you decided what level of bass and treble you want. Since they are custom in-ears you also get to choose the color and graphics if you want that.

The Sleek-Audio concept of letting the user decide which type of sound they want has made them one of the top brands when it comes to in-ears. The custom earphones they produce do not allow you to swap sound ports like on the universal SA6, but because they are custom fitted, the comfort and other aspects of their performance might be better. The pricing for the custom made ones is a bit higher than that of the SA6s, which can be had for around $200 plus shipping on the web, the price for a basic Sleek-Audio Custom earphone is $299 that is excluding shipping, impressions (which usually cost around $50) and custom artwork.

Performance

I am very fond of the old Sleek-Audio SA6 design and have been enjoying those in-ears for quite a while. The configuration that suits my needs the best is with the bass “plus” port and treble “plus” tube. So I had my custom Sleeks made to the same specification so the only differences in sound between the two should be down to the difference in materials and the fact that the customs do not have a silicone tip, that to some extent does alter the sound.

The custom Sleeks are a very different design compared to its universal styled cousin the SA6s so just because they are made to sound alike does not mean they will perform identically. The acoustic properties of the materials and the shape can affect the sound quality greatly. The Sleek-Audio Customs are a single balanced armature design so nothing has changed there since the original SA6s. The in-ears I will be comparing the Sleek-Audio Customs in-ears to are the following: LiveWires T1 Custom earphones, Sleek-Audio SA6, Yuin OK1 earbuds. I used the same rig to compare the earphones, which consists of my Cowon D2 DAP hooked up to a Ray Samuels Audio Tomahawk earphone amplifier.

Like the old Sleek-Audio SA6 earphones the new custom ones are medium sensitive for a pair of earphones which is alright because it means that they do not hiss as much when using them on a noisy source.

Surprisingly enough the custom Sleek earphones with supposedly the same configuration as the SA6s sound quite a bit different. One of the noticeable differences is that the mids and highs are a wee bit more dominant and that it has a more liquid, airy quality to the sound. The SA6s are anything but muddy, but in comparison to what the custom version offers they are clearly out shined in when it comes to smoothness and detail. The midrange bears some resemblance to that of the SA6 when it comes to intensity, but it is a little more refined and gives you are a more smooth sound which is quite nice. It still carries the same detail, it just sounds a wee bit more natural, this could be because of the coloration the SA6s get from the silicone tip. The bass is pretty much the same, it is a little tighter and extends a little lower on the custom Sleeks.

The midrange is really the Sleek-Audio custom earphones’ strongest side. It is smooth, neutral, and very detailed with a great sense of ambiance. Compared to custom earphones such as the LiveWires the midrange of the Sleek-Audio ones are much more forward in the mix, taking a much more dominant role in the music, bringing forward instruments such as guitars, and vocals. The LiveWires’ primary focus is bass, and while it does that nicely some would probably argue it was a bit too dominant. The Sleek-Audio custom in-ears strike me as having a lot more neutral sound with less bass and more mids and highs. Bass extension still is about the same as that of the LiveWires, but it is less intense. The bass lacks the full powerful sound of the LiveWires, but that said, it is far from the worst bass performer I have heard. If you are looking for a pair of basshead in-ears, the Sleek-Audio ones will probably leave you wanting more. They simply cannot deliver the slam like what I heard from the LiveWires, however, if you are biased towards a more neutral frequency response you should definitely have a look at the Sleeks. For rock I found the Sleeks to have about the right amount of bass, and they are more analytical in their presentation than the LiveWires.

The high end is just about perfect, it has a good amount of sparkle without sounding harsh or sibilant on normal records. The treble extension is the best I have heard in a long while and the definition is incredible, leaps ahead of the LiveWires in that respect. The great part about it is that you can customize the earphones to sound the way you want them. If the treble tuning works just as good as exchanging treble tubes on the SA6s you can trim it to your needs right from low treble to sparkly. I had mine built with the treble plus tuning, because I enjoy a sparkly presentation of music with a bit above average treble energy, and the Sleek-Audio Custom in-ears provide just that. The treble is really refined delivering oodles of details and it has just the right level in order to be an integral part of the sound without being overly dominant or tiring to listen to, due to sibilance. On just about any track with half-decent mastering the treble is just where I want it, but on some lousy recordings it is a bit shill, but that is not the earphone’s fault. The sound stage is pretty good for set of in-ears, it is quite wide but lacks depth. Left to right separation and space is quite good, reminds me a lot of my LiveWires. You get a real sense of layering in the music from the Sleeks even in the busy parts of a recording, to a much greater extent than on say a pair of SA6s or LiveWires for that matter. Sound stage is still nowhere near what you can get from a pair of Yuin OK1s, but that is almost an apples to oranges comparison due to the fact that the OK1s only function well as earbuds.

Like the SA6 earphones the custom Sleeks have the same cable which means that they have the same characteristics when it comes to microphonics. The disturbance is very little with the cable worn over the ear. Only the LiveWires are less effected by microphonic noise than the Sleeks but they also feature a much softer more volatile cable with an extremely soft coating on.

Noise attenuation wise these block out just as much noise as my other in-ears no noticeable difference here.

Durability

The Sleek-Audio Custom in-ears are really durable. The hard acyclic shell will withstand normal wear and tear easily. All the joints between the acyclic shell pieces seem well bonded together and are almost invisible. If you carry the earphones around in the box they ship in they will be impossible to break unless you use a nuke, but then your DAP will most likely be fried. The cable is of a good quality and so are both the male coaxial plugs and the mini plug on the end. However, do not expect miracles it is still a thin cable with a minimum number of protective layers in order to keep the weight and microphonics down.Value and Conclusion

Review By: Frederik S. http://www.techpowerup.com/reviews/Sleek-Audio/Sleek_Audio_Custom/1.html