The Sleek Audio SA6 W-1 Wireless Earphones Kit Review

Late last year I was introduced to Sleek Audio, and among their earphones’ features, I was impressed by their unique method of insuring a customized listening experience through the utilization of removable and interchangeable in-ear ports – even on their entry level model, the SA1. While I enjoyed the SA1 earphones very much and was quite impressed with their quality, I couldn’t help but wonder what it would be like to use one of their more specialized sets, specifically the Sa6.

Not long ago I was given the opportunity to review the SA6 W-1 Wireless Earphones Kit, a combination of the SA6 earphones and Sleek Audio’s W-1 Wireless kit, which utilizes KLEER wireless technology. As I mentioned in the SA1 review:

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.”

It took Mark and Jason three years to develop exactly what they wanted, and then they introduced the SA6 acoustically customizable earphone. What set the SA6 apart from other earphones was that it was the world’s first to be acoustically customizable, and it could “go from wired, to wireless and back again.”

Everything about the SA6 points to their uniqueness, beginning with the way the earphones are packaged unattached from their 3.5mm cable.

Opening the box reveals a carrying case, a collection of Small, Medium and Large pairs of dual-flange silicone ear tips, and …

… a collection of interchangeable treble tips and bass ports along with a 54″ long replaceable cable. As I mentioned in my SA1 review, the option of being able to easily replace the cables is very attractive to me, because “every set of earphones that I have ever had to stop using (for reasons other than because I gave them away or I lost them) was discarded because something had happened to their cable – whether it was my cat chewing on them or some other “natural” disaster.” Another reason for interchangeable cables is color matching, which Sleek Audio says will be available this year.

As mentioned when I reviewed the SA1, I would like to see the option of purchasing a tangle-free cable, like the ones on the Zagg Z.buds I reviewed in 2008. I like that type cable best because they are nearly impossible to accidentally knot, and the way the cables are wrapped helps preserve the wires held within. Hopefully Sleek Audio will have that type cable available soon.

Tucked under the silicone ear tips is a plastic tool which makes removing the bass ports and treble tips from the earphones extremely simple. Unlike the SA1, these removable tips and ports are easily discernible from one another — treble tips by their gray or yellow coloring, and bass ports by their + or inscription. The earphones come with neutral treble tips and bass ports installed.


  • Standard Cable: 54 inches
  • Impedance: 50 ohm
  • DC Resistance: 24 ohm
  • Speaker Type: Ultra Wide Band Balanced Armature Driver with Custom Porting
  • Sensitivity: 110 dB SPL/mW

Also included is a cleaning tool, because these are in-ear earphones, and let’s face it — wax happens, and when it collects you’ll need a way to remove it.

The body of the earphones is composed of black matte and shiny silver plastic.

Instead of adding multiple drivers and the necessary passive-crossovers which add color or distortion, we used a different approach. We started with a subminiature, ultra-wide band balanced single armature driver and developed the VQ System to acoustically alter the frequency response to personalize your music.

We designed the VQ System specifically for this incredible driver; because music is personal and the headphones should never get in the way.

At the butt of the earphone, you can see the black neutral bass port; it pulls off when you are ready to experiment with other bass amounts…

… and you can insert one of the other ports for a different sound.

Here is the earphone body with its neutral treble tip removed.

Also included are a set of extended high frequency treble tips.

Due to the SA6 Variable Equalization (VQ) System, which is essentially composed of the treble tips and the bass ports, the sound produced will be some of the best you have ever heard, and certainly the most personalized.

The VQ System, or Variable Equalization System, is the first of its kind in an in-ear monitor.
This multi-stage system allows you to completely customize the sound of your music. While you may appreciate brilliant treble, someone else may want deeper bass. Now, with the VQ System, all listening experiences can be tailored: from symphony to hip-hop, or country to rap, everyone can have the sound they love.

First, using Interchangeable High Frequency Filter Tips, the end-user can dramatically alter the sound of the high frequencies to adjust the amount of make up gain they need after inserting sound isolating in-ear monitors. It may be that you like sustained high-frequencies with a peak at the vocals. Or it could be that you want a flat response with some roll off at the upper high end. The choice is yours with our Interchangeable Treble Tips.

Second, low frequency response is a personal preference. Our patent-pending Variable (Interchangeable) Bass Port System maximizes the low-end bass curve. The result is a dramatic 12db difference at 20 hertz between our three interchangeable bass filters, with no effect on the high-frequencies. This is an industry first.

So now comes the part where you have to decide what YOU like. Do you want to hear more thump with less treble in your left ear and a bit more treble with less thump in your right? Or would you prefer something completely different? It’s up to you to experiment, mixing and matching the treble tips and the bass ports until you find the sound that satisfies you … and make no mistake about it, you will.

Unlike other earphones I have tried, the SA6 were truly made with music-lovers in mind. The SA6 earphones sound great right out of the box with their neutral ports and tips in place. But once I started experimenting with the treble and bass bits, I felt like a whole new soundscape was being opened to me.  Music sounded more lively and multifaceted; bass had incredible punch – but it was crisp and resonant, not bottoming out. Trebles were clear, but not piercing or tinny.

All of the best in-ear earphones offer noise isolation and a sense of being more immersed in the music, and in that regard the SA6 certainly delivered. The ability to equalize the sound right at my ear made the experience all that much unique and personalized.

If you’re not the most organized type, and the idea of all these little bits just waiting to be lost makes you nervous, rest assured that you can purchase replacement parts of just about every component — including single earphones — should it ever become necessary.

As if the SA6 wasn’t impressive enough, it has one more trick up its sleeve. Using Kleer Wireless Audio technology, “which offers uncompressed, lossless, digital stereo CD quality sound wirelessly and with low power consumption,” you can attach the earphones to the SA Wireless kit, allowing you to enjoy 10 hours of music without being physically attached to a digital music player or laptop.

Included in the Wireless kit is the 3.5 dongle, which plugs into the audio source. An audio extension cable is included, and it’s a good thing because without it you could forget plugging the dongle into the iPhone’s deeply recessed audio jack. There’s a soft carrying pouch and a split simultaneous charge USB cable which will take care of the earset and dongle at the same time.

The earset and dongle are shipped already paired, and they should be allowed to charge for at least two hours. During charging, an LED will glow red; it will turn off once charging is complete. The one caveat is that you must have the power switch on each device turned ON in order for them to take a charge. The on / off switch is a tiny little slider under a protective cover, and it should be switched off when you aren’t using the set. I wish that there had been a more accessible place to put it. but using a pin-tip or other pointy object helps.

The beauty of the Sleek Audio system is that every earphone set they make is wireless compatible; if you are using the Wireless kit and the battery runs out on them, you can just plug the earphones back into their cable, and they will immediately work as a cabled set. Because the earpieces are in-ear and the earset is so light, you can easy jog or do any other activity without fear of losing the headset. That alone may make the price of the wireless upgrade attractive to activity-inclined buyers.

I knew going into this review that the KLEER system is supposed to blow away the sound quality of Bluetooth headsets, so I expected improvement. What I didn’t expect was for music to sound essentially the same whether through the wired or wireless earphones. In a word, this option was amazing. Being able to leave my audio source in one place and move freely throughout the room without being connected was nice. The Sleek Audio site says that the dongle will transmit up to 60 feet; I tried it up to about 50, and it worked well.

The Sleek Audio SA6 W-1 Earphones Kit is the complete audio package for anyone who wants total control over how and where they will listen to their music. Being able to customize the sound and the method of delivery without giving up any quality is an amazing option, one that makes this kit easy to recommend.

The Sleek Audio SA6 In-Ear Earphones and the SA6 W-1 Wireless Earphones Kit are available directly from the manufacturer.

MSRP: $249.99 for the SA6 earphones, $320 for the SA6 W-1 Earphones (or $120 when purchased separately).

What I Like: Interchangeable and removable cable allows for easy cable replacement or transition to wireless; Ability to convert to wireless earphones and back to wired; Excellent sound and noise isolation; very comfortable, even after extended periods of wear; multiple ways to completely customize the bass and treble for your listening enjoyment; amazing KLEER sound over the wireless headset kit; long battery life on the wireless set

What Needs Improvement: On/Off switch on the wireless set components is hard to access

Categories: Reviews

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8 replies

  1. You realise, Judie, that the only way is up? Next stop, Sleek Audio CT6 Customs – they sound even better than the SA6s… 😉

  2. Chris, I am sure you are right … but part of me has to wonder how that is even possible?! :-))

  3. I wondered that too, but trust me :) Excuse the link-whoring, but my review of them is here:


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