Sennheiser Spectera WMAS Ecosystem Debuts at IBC2024

IBC, Amsterdam (September 16, 2024)—At IBC, Sennheiser has introduced what it describes as the world’s first bidirectional wideband solution, Spectera, which uses WMAS (Wireless Multichannel Audio Systems) technology,

​Sebastian Georgi and Jan Watermann are the inventors of the specific Sennheiser approach to WMAS. “Instead of many individual 200 kHz narrowband RF carrier frequencies, we use a single wideband RF channel for audio transmission—bidirectional transmission of audio and control data, to be more exact,” they explain.

“In Sennheiser’s approach, the wideband RF channel is a TV channel of 6 or 8 MHz, depending on local regulations. The WMAS system organizes its audio links within this channel. Every audio link, be it a mic or an IEM, is assigned specific time slots for transmitting its audio information. For the first time, it is possible to have IEMs and mics in the very same TV channel instead of two channels separated by a guard band.

“Thanks to the fact that all audio links use the full width of the RF channel when it’s ‘their turn,’ RF fading is greatly reduced. It corresponds to 40-fold diversity for an 8 MHz RF channel and 30-fold diversity for a 6 MHz TV channel. Also, the spectral density is low, which makes it easier to reuse frequencies, for example on a larger festival ground, between neighbouring theatres, or in a broadcasting complex,” they conclude.

​The Base Station is the heart of the Spectera ecosystem, handling up to 64 audio links—32 inputs and 32 outputs­—in a 1RU device. One Base Station accommodates up to two RF wideband channels. The Base Station is frequency-agnostic; activation of the respective local license for the Base Station will automatically load the authorized frequency ranges.

The SEK Bodypack can handle both IEM and microphone or instrument requirements and can be flexibly determined and changed during a show. The bodypack features a 3-pin connector for a lavalier or headset microphone or an instrument cable. The 3.5 mm headphone jack connects to Sennheiser’s range of professional in-ear phones and features an impedance-matching high-power headphone amplifier. Device information is retained on the display even when a unit has been powered down. The bodypack is available in a UHF (470 – 608 MHz and 630 – 698 MHz) and a 1G4 (1350 – 1400 MHz and 1435 – 1525 MHz) frequency variant.

FCC Enacts WMAS Rules, Allowing More ‘Spectrally Efficient’ Wireless Mics

​The IP 54 protected DAD antenna is a transceiving antenna that manages mic/line signals, IEM signals and control data at the same time. The antenna carries the RF components of the system, eliminating the need for boosters, splitters and combiners. Because the RF is digitized in the DAD, the antenna does not use a BNC connector and co-axial cable for connection to the Base Station, but a ruggedized RJ 45 connector and CAT 5e cable instead.

The LinkDesk desktop application runs on Mac or PC and turns it into a remote control and monitoring center. The operator can flexibly choose between the audio link modes with their varying levels of audio quality, latency, possible audio links and range, as well as fully remote control, and monitor the entire system, with visibility of all audio settings and RF statuses.

The LinkDesk software also handles the activation of the Base Station via single node-based licenses. By entering the specific local license code, the software ensures that the system operates within the local regulatory requirements for frequencies, RF channel bandwidth, and transmission power, putting operators on the safe side regarding compliance.

​Spectera can be pre-ordered from today. The date when shipping commences will be announced during the first half of 2025. All through 2025, a special introductory pricing will be in place.