The 2012 Sennheiser Sound Academy RF Wireless Seminar in New York started with a vocal “tsk” from Joe Ciaudelli, director of Market Development and Education at Sennheiser, to check his microphone volume. He then introduced the presenters and gave a short presentation on the propagation of waves.
Presenting were Ciaudelli on waves and frequencies; Uwe Sattler, director of Technical Services at Sennheiser on modulation and frequency selection and coordination; Andrew Funk, I.A.T.S.E. Local 1 sound engineer on system configuration; Volker Schmitt, director of Product Lifecycle Management at Sennheiser on antennas and new digital technology; Henry Cohen, president of Production Radio Rentals on coaxial cabling and the new Federal Communications Commission laws; and Ben Escobedo, RF Services and field support engineer at Sennheiser on in-ear monitoring and computer monitoring and control.
This seminar has something to offer sound professionals at any level of understanding of wireless audio transmission from early career stagehands, to designers or engineers looking for guidance on how to properly tune their black box theatre system, to seasoned professionals on Broadway and veterans of the broadcast and arena touring fields.
One highlight was an explanation of new features recently enabled in firmware updates to Sennheiser’s Evolution series of in-ear monitoring devices. Focus mode allows the engineer to utilize the stereo inputs on the transmitters in mono mode so that you can bus two different signals to the artist wearing the in-ears, allowing the artist to create their mix on the beltpack. A good sample implementation would be a band mix on one channel and a vocal mix on the other. so that the vocalist can turn herself up in comparison to the band as much or as little as she wants. Engineer mode enables the engineer to set up a single beltpack that can be set to 16 or 32 different presets (pending the model) that are identical to receivers on stage, creating a virtual in-ear cue wedge.
What I found most informative as a mid-career professional was Sattler's presentation on the challenges of digital audio transmission. In it, he described the methodology behind QAM (Quadrature Amplitude Modulation) digital compression, how said compression used in Sennheiser’s soon-to-be-released digital systems is able to handle uncompressed digital audio (18-bit 44.1k sample rate), and why it is necessary to use such techniques. For anyone to whom radio transmission is voodoo, adding digital audio to the mix only complicates matters, but Sattler clarified greatly the ways in which Sennheiser will add the layer of digital audio to their radio microphones.
While the day started on time with a small “tsk,” it ended 30 minutes late with Ciaudelli’s high praise of wireless microphone and communications guru Cohen. For anyone who attends or works professional development seminars often, a late ending is a very surprising turn, but this one ran long due to very heavy interest in Cohen’s presentation on the recently enacted Federal Communications Commission regulations on “white space” wireless spectrum issues. His extensive information on the subject held the attendees in rapt attention so much that no one, myself included, noticed that the scheduled end of the day had passed.