SurroundControl is our flagship product line for controlling, analyzing and monitoring stereo, surround sound and multichannel programs. It combines the metering functions of the RTW surround display devices and the control functions of an eight-channel monitoring controller - a true high performance system. Loudness measurements of version 4 follow all relevant loudness standards: EBU R128, ITU-R BS.1770-3/1771, ATSC A/85 and ARIB. Therefore, extensive functions are available. For example, the LRA instrument combines the measurement and visualization of two critical loudness parameters (program loudness, loudness variances within short time periods) in a straightforward and intuitive way. The 3G/HD/SD-SDI deembedder interface option expands the audio signal analysis to 3G-SDI data streams and surround format 7.1 DD+. Depending on the model SurroundControl is already equipped with it. All delivered version 4 units can be upgraded by factory (--> see Options). For existing units with software version 3 (03.00.nn) an upgrade kit to version 4 is available.