The OC818 offers four selectable onboard polar patterns: figure-8, supercardioid, cardioid, and omnidirectional, giving you immense flexibility when it comes to exploring the sonic possibilities offered by different recording techniques. The fifth setting is Preset mode, which works in tandem with the optional Bluetooth dongle that plugs into a port on the rear of the mic body and lets you program custom patterns. Austrian Audio microphones are rigorously tested on state-of-the-art measurement systems and precision matched to within a stringent 1dB tolerance — which means that with two of these excellent microphones, you can confidently implement stereo techniques such as Spaced Pair (A/B), X-Y (including Blumlein), ORTF array, Mid-Side (MS), and Spaced Omni (with or without a center mic). It's worth noting that a single OC818, with its two separate XLR outputs, is a stereo microphone in and of itself. But with two OC818s, your options expand exponentially.