Introduction

Sleek-Audio has always been pushing the envelope when it comes to in-ear design, and now they have even made a clever way to remove one thing that has always been an issue with in-ears, namely the cable. The Sleek-Audio W1 Wireless Adapter comes as a kit with a transmitter and a receiver which allows you to use it with your current set of Sleek in-ears.
The installation is hassle free due to the fact that Sleek's in-ears all feature the same type of coaxial plugs on the monitor itself. The wireless system is made by a company called Kleer which enables lossless transmission of audio through a wireless connection, unlike Bluetooth which has a negative impact on the sound quality. The Kleer system used has a throughput of approximately 2.4 Mbps which is not a lot, but enough to get the job done.

The Sleek-Audio Wireless system can of course be used with both the original SA6 earphones and the recently launched Custom IEMs from Sleek. You can read those reviews here: Sleek-Audio SA6 Review, Sleek-Audio Custom Earphones Review

Specifications

• CD quality, lossless sound
• 10 hours of independent battery life
• 4 people can listen to one audio stream
• 60 feet of freedom
• Compatible with any device you can plug earphones into

The specification list for the W1 is somewhat short, however, it sums up the essence of the system. The lossless transfer of sound from the host device to the receiver is definitely one of the things that makes the Kleer based solution from Sleek interesting for audiophiles and people who enjoy a solid sound quality. During the course of my testing I averaged a bit over 10 hours of battery life which is nice. This may vary according to what volume you listen to. The 60 feet part is probably about right as long as you can see the unit. It will not push the signal through walls or anything like that.

"The claim of lossless sound is not 100% correct at least according to the manual, where it states that the sampling rate is only 16 kHz, since the sampling rate of a CD is 44100 Hz or 44.1 kHz." - It seems that there was an error in the Sleek-Audio manual, the sampling rate of the Kleer transmission system is indeed 44.1 kHz or CD quality equivalent. The current revision of the Sleek-Audio manual states 16 kHz, the right value is 44.1 kHz.

Some loss of sound quality is to be expected. Also the fact that it puts an ADC and a DAC in the signal chain will also most likely have a negative effect on the sound quality.