Hey there!
We’ve just finished a 3-day recording session with the Soundcraft UI24r directly recording to Ardour 5 with a standard USB-B cable (that I obtained from a Canon scanner from the stone age) onto a HP Elitebook 8470p (i7-3520M,12GB Ram, 2xSSD-drives) with KXStudio using all of the 20 input channels simultaneously for live recordings of drums, guitars and bass. We didn’t apply the latest firmware update, but used version 1.0.7.
To me personally, this thing is an awesome revolution. All of our previous recordings were made with 2 daisy-chained Edirol FA101 (Firewire) and an analog Soundcraft FX16 with a ton of patch cables allowing for 16 inputs simultaneously. And the ui24r is just so much easier to set up and a lot more reliable. No additional need for obscure Firewire express-cards that have this one particular Texas Instruments -chipset, no connectivity problems at all and no complete freezes on occasional xruns (xruns did occur though).
We’ve just plugged it in and everything worked out of the box. Though the user interface of the ui24r takes some time to get used to because it has an abundant amount of functions and sub-menus to dig through and the routing is not very intuitive, recording itself was without any hassle, especially when compared to the mess you have to get used to when trying to do this with Firewire.
For the recording session we controlled the ui24’s internal interface with a second laptop (connected via LAN-cable) and a tablet (wifi) to set mic gains and channel routing and separated the first laptop for recording to the DAW exclusively. The usb-connection was rock solid, although we did encounter quite a few xruns in almost regular intervalls. I cannot tell if this was due to insufficient hardware on the DAW-side (e.g. laptop-cpu, hard-drive) or if this was a flaw with the ui24 itself. Nevertheless, the xruns that occured in some of the best takes we’ve recorded surprisingly didn’t break the recorded take. Whenever that happened with our previous Firewire setup, the recording was simply unusable due to significant lag. With the usb-connection to the ui24, the problems with xruns were barely noticeable.
Additionally, we now use the ui24 as a device to record our regular rehearsals with up to 14 tracks on a usb-key. The internal buffer of the ui24 is pretty reliable when it comes to secure a constant recording to the usb-key although on some occasions, where we wanted to record a live gig and where the ui24 was also the live mixer for the concert itself, recording rarely dropped out due to the buffer being exhausted.
For me, when recording to a usb-key, it’s a charm to start/stop and control the preamps with a tablet in hand while sitting at the drumset. Awesome. Our sound engineer uses the ui24 mainly as a device for FOH-mixing and he is pretty happy with the fact that he can walk around the venue with his Samsung tablet and control the sound that way.
Besides the complexity of the sub-menus, another downside of the ui24’s browser-interface is the fact that it always behaves like a touch-optimized tablet surface. This takes a short time to get used to when using a mouse (no right-click, scrolling via left-click a and drag, context-menus via long-press left button).
I can’t say anything about the preamps besides that they sound nice to my ears and didn’t cause any irritating ground noise.
And, well, I didn’t test any other device in that category so far, but for the many applications we use the ui24 for and for the unbelievable low pricing, I fully recommend this device.