The Sennheiser EW-D SKM-S (S1-7) is the digital UHF handheld transmitter from the Evolution Wireless Digital (EW-D) series, supplied without a microphone module so the user can fit the capsule of their choice. It accepts a wide range of Sennheiser and Neumann screw-on capsules (for example the MMD 835, MMD 845 or MME 865, all sold separately) and has a mute switch. This S1-7 version tunes 606.2 - 662 MHz, the range used in South Africa. Digital transmission gives a 134 dB input dynamic range, so there is no need to set sensitivity, and an equidistant 600 kHz tuning grid allows up to 90 channels in the 56 MHz bandwidth. Setup and monitoring are handled through the Smart Assist app over Bluetooth Low Energy. It runs up to 8 hours on the two supplied AA batteries, or up to 12 hours on the optional BA 70 rechargeable pack. Latency is 1.9 ms. It pairs with the EW-D EM receiver.