I've looked at your current setup and gear. Using your Delta 66 interface and just upgrading the mixer, the Behringer X-air 12 is the clear winner and I would not consider USB because you already have a better quality interface and converter with more ins/outs than offered in mixers in this price range including the XR12.

Considering the small footprint, that the device can be placed anywhere in your studio and that your use is primarily for the studio, the Control Program offers so much more of full featured channel control per channel, plus quality effects at 40 floating DSP, dynamics (gate, eq and compression per channel) and it is a full compressor rather than a preset one knob partially featured, design of the 1832usb

All of the controlling you can do from the Control Program Editor place zero load on your CPU, all the processing is done on the external unit. No other mixer in this price range comes anywhere close to the useful features of the XR12.

Here's a link you can review the Control Program - X Air Edit Control Program

With the XR12, you're getting a full-featured digital mixer at a very good price.

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