by Nebuch

Pros: Great sound clarity, high efficiency (easy amp load), blocks outside noise
Cons: Treble tubes are hard to remove

The Sleek Audio SA6 are excellent in sound quality. I compared the sound quality to my Grado SR-60s and while both units have great sound, the SA6 excelled in midrange and treble clarity. High frequency content like cymbals are crisp but not harsh. The low frequency content of both units are about the same. The SA6 is very enjoyable to listen to and I had no problems of listening fatigue.

The clarity and accuracy of the SA6 are it's biggest asset; however, any problems with the source sound are very apparent. Poorly mastered CDs with clipping signals are plainly heard as distortion and noise. This is not the fault of the SA6 and properly mastered recordings sound excellent.

An interesting feature of the unit is the ability to modify the sound. My preference is the bass+ and extended treble (black tube) bits. One problem I encountered with the SA6 is the difficulty of removing the treble tips. While I was removing the original treble tubes the plastic housing cracked on one ear piece and it stopped producing sound. After fiddling with it, sound returned to the ear piece, but now I am apprehensive of trying to change the treble tip again. It concerns me that a feature has a possibility of damaging the unit. I heard that Sleek Audio is planning a treble tip removal tool which may avoid these problems.

The SA6 are an in-ear unit which took me a while to get used to, but are now very comfortable. The flanges work well to hold the unit in the ear and to block outside noise. When inserted it feels like I'm underwater and I can hear all the weird noises my body makes, but once music is playing it feels fine. The flanges do an excellent job of blocking outside noise.

The SA6 are very efficient and a low volume setting gives plenty of loudness. Because of this, the user should be cautious about ear damage. The efficiency and impedance of the SA6 provide an easy load for amplifiers so an external amp should not be necessary.