This ultra-slim USB controller keyboard and audio interface packs in an awful lot.
You get 25 keys, mod/pitch wheels, eight knobs, a few buttons (including transport section), LED display, stereo RCA line-in and outs, expression and sustain pedal inputs, MIDI Out, mini-jack headphone and mic sockets (which 'mirror' the signals on the RCAs) and direct monitoring controls.
It can be powered by USB, batteries, or PSU (though one isn't supplied).
All of which is not bad considering the 18.1x8.7x1.8 inch footprint. Plus, the unit looks a million bucks, with a shiny red casing and a smart design.
To top it off, there's a carry case, strap (for keytar-style playing), headset and a decent software suite thrown in. But at 80 sheets, is it too good to be true?
While initial impressions are good, the experience is soured by the Windows ASIO drivers for the audio interface element. They'll only install the device on the USB port the keyboard is plugged into during installation, and won't enable you to either change ports without reinstalling or use another audio interface on that port.
Though these deficiencies are detailed in the driver's ReadMe on the bundled CD-ROM, they're not mentioned in the installation procedure. In fact, the latest version of the driver on the Behringer website doesn't have any documentation at all!
We ended up using ASIO4ALL instead, and this seemed much more satisfactory. And on the Mac, it works perfectly well as a plug-and-play Core Audio device.
We also had a few problems with the hardware itself. The level knobs around the back are fiddly to get at, and the keys have little travel, which makes accurately inputting velocity levels tricky. More crucially, it's all too easy to distort the headphone out, even at low levels.
On the plus side, the RCA inputs work fine, and the eight MIDI knobs feel solid. The included peripherals are also genuinely useful.
Our feelings about the UMA25S are mixed. It certainly looks the business, is well built and fully-featured, but the headphone output and ASIO driver issues make the audio interface element less useful than it might have been.
We can't recommend the UMA25S unreservedly, but those after an extremely cheap all-in-one solution to meet their mobile music-making needs will find it offers good performance for the price, as long as they can live with the issues we've raised.