Taken from : //www.macnn.com/reviews/killer-concepts-rocksteadyxs.html

Killer Concepts RocksteadyXS

February 19th, 2013
Killer Concepts takes a shot at a loud yet compact Bluetooth speaker.

Headphones and portable speakers are, for my money, still the best uses of Bluetooth, at least when it comes to audio. There are other options, like connecting to a full-sized stereo or car system, but in those cases there are often equally convenient alternatives with better fidelity. It\'s when you\'re traveling somewhere that fidelity takes a back seat to qualities like compact size, or minimizing wires. On the surface the RocksteadyXS seems to fit that bill; we\'ll put the hardware to the test in our review.

As you\'d hope for, the XS is very easy to set up. The speaker charges via a micro USB/AC adapter, after which you can flip on the power and tap the Mode button to enable pairing with a phone, tablet, or other Bluetooth audio source. Cue sounds let you know when everything is connected. Alternately the XS can accept input through a 3.5mm jack, or play MP3 files stored on a USB stick.

One perk of the unit is that its rechargeable battery should, in theory, support up to 10 hours of Bluetooth playback. In practice it\'s better to avoid pushing the battery that hard, but that still puts the XS on par with some of the better portable dock speakers, which don\'t even have to stream Bluetooth content. There are some legitimate issues surrounding charging the XS, however; for one, the supplied charging cable is far too short. It can also take as long as four hours to top off an empty battery, so you may end up plugging in the speaker regularly anyway to avoid waiting.

Track control is handled using either a source device\'s interface or front-mounted buttons. These are pretty straightforward, but I will say that it\'s annoying that the power button is located in the rear, meaning that you have to turn the speaker over to switch it on.

As far as output goes, Killer Concepts likes to brag that the XS is one of the loudest portable speakers out there. It\'s certainly loud enough -- in a quiet room, you\'ll probably want to keep it well below full volume. Quality, however, is merely reasonable. Sound is usually clear, but tends to distort slightly at high volumes. The XS also lacks any serious bass punch, but that\'s to be expected from a portable speaker, especially one as small as this.

Aesthetically the speaker is nondescript, forgoing any real style except for the subtle placement of a color-changing status light. The tradeoff is that the speaker is housed in a tough yet light aluminum block, making it better for travel than some of its rivals. It\'s also compact enough that it should slip into a bag or briefcase without much trouble.

Another thing I have mixed feelings on is the battery slot on the bottom. It\'s refreshing, on one hand, to see an electronics maker add a swappable battery in an era when many companies are eliminating the option. The XS though uses a relatively cheap plastic lid that\'s difficult to open. It\'s also unlikely that you\'ll be able to buy batteries from anyone but Killer Concepts, even though retailers are expected to carry them. On top of that, I would be worried about putting the speaker on a wet surface -- it could be relatively easy for liquids to seep into the battery compartment.

In the end, the XS won\'t set the world on fire, but it doesn\'t really intend to. It just attempts to provide loud sound in a convenient format, and in that it mostly succeeds. Arguably, its real strength is price; some retailers are selling it for under $100, and if you can get it for that, any minor setbacks are easy to cope with.
- Loud, reasonably clear sound
- Compact, lightweight, durable
- Replaceable 10-hour battery
- Low price
- Sound distorts slightly at high volumes
- No bass punch
- Relatively plain design
- Battery compartment could leave speaker vulnerable to liquids
- Short charging cable
- Long charging times