The Signature 12MTK & 22MTK feature the same exact specifications as their standard, blue variants, however they combine that same classic analogue circuitry with a 14in/12out and 24in/22out USB audio interface (respectively) that allows the consoles to send all of their input channels to a DAW as individual channels to be recorded, mixed, and processed later on.
This makes the MTK’s a perfect for choice for small studios or musician’s looking to make their own demos, or simply record a drum kit with multiple mics. The ability to record so many channels makes the MTK a really affordable choice for engineers who need to record the maximum amount of channels. The 22MTK for example can record 16 mics simultaneously. To get that many channels of recording with normal interfaces, you would be looking at paying double – and that price doesn’t take into account the full analogue mixer you get with it!
What makes the MTK’s even more powerful is that each channel also features a USB RTN switch that toggles the input source of the channel strip between the XLR socket, and the USB return. This allows you to send those channels from your DAW directly into each analogue input channel as if they are being played ‘live’, allowing you to get your hands onto the faders, and mix the audio naturally and intuitively using the faders, EQ, and effects.
More information can be found on the Soundcraft MTK models via 'Our guide to the Soundcraft Signature 12MTK & 22MTK consoles' blog.