Sleek Audio's SA6 earphones, which have been on sale for a while, now also come in a completely wireless edition -- and not using Bluetooth either, but rather the lossless Kleer technology.
They're on sale now from hifiheadphones.co.uk for around £250, and we've been giving them a test drive for a few weeks.
The default set-up involves using the earphones wirelessly by hooking a lightweight receiver around the back of your neck. It's comfortable, lightweight and discrete, and suitable for running or the gym when worn correctly.
If the battery runs out, you can simply unclip the bits of the earphone that you put into your ear from the wireless receiver, plug them into the traditional headphone cable supplied, and use them as a normal pair of wired earphones. It's an extremely simple procedure, taking less than 5 seconds.
Compact and lightweight, the SA6s are a comfy pair of in-ear speakers. We had several continuous hours of usage without any 'canal fatigue', but whether or not this will be the case for you will depend on the size and shape of your ears, and the size of the tips you use.
Decent levels of sound isolation can be achieved using the tips provided, but we recommend investing in a pair of Comply's compatible tips for even greater comfort.
In addition to their modular design, the SA6s use Kleer's wireless audio system. Kleer transmits audio data losslessly, so absolutely no audio quality is stripped out during the broadcast from transmitter to earphone, unlike with Bluetooth. This means, if you're listening to lossless audio on your portable player, you're not going to miss a single bit or byte.
A single armature is used in each earphone, and we're told it's the same armature used by Klipsch in one of its high-end earphone products. They respond to frequencies between 20Hz and 20kHz, with an impedance of 50 Ohms and a sensitivity of 110dB/mW, and utilise a data rate of 2.4Mbps for transmitting the wireless audio.
Not a million miles away from the sound of some Klipsch earphones, the SA6s deliver an impressive and clear sound quality that's particularly suited to vocals and acoustic music. Their robust mid-range is backed up by a strong, but not ultra-powerful, bass, and a sweet treble offers delicious highs, without being harsh or venturing into territory that can make music sound too bright for its own good.
Compared to the Klipsch Image X10s -- a very similar earphone -- the SA6s have a more balanced sound, with a subtler treble, while the X10s offer a much deeper bass. The Klipsch Image X5s are even more similar to the SA6s, but don't quite offer the SA6s' velvety-smooth overall tone. We'd say that, if you like rock, pop and metal, get the X5s, but get the SA6s if you like vocals, acoustic guitars, folk and country.
As wireless earphones, we had hit-and-miss results. Around the office and home, the wireless adaptor, which connects to any 3.5mm audio socket, proved flawless in terms of reception. We could get a good few metres from the transmitter, but the distance you can achieve will largely depend on your surroundings.
Outdoors, however, we had issues. With the transmitter in our pocket during a walk to the office, reception was intermittent. This was primarily caused, it seems, by our neck problematically residing between the transmitter and receiver. We eventually gave up and used wireless in the office and wired on the commute. This is an issue we have had with most wireless earphones.
One other wireless-related criticism is that we noticed a delicate and faint buzzing when using the SA6s in quiet environments. It's only really noticeable in silent situations or during extremely quiet parts of songs, but it's definitely there.
You should get about 8 to 10 hours of continuous battery life from the system.
Considering all wireless earphones of this style seem to suffer reception drop-outs when on the go, the Sleek Audio SA6s can't be criticised too much for this flaw, but we would have loved this to have been the pair that resolved the issue.
When wired on the commute or wireless in the home and office, however, the SA6s are stunning performers, particularly with acoustic, vocal and softer music, and they're also decent with general rock and pop.
Edited by Charles Kloet