By Mike Wireless • November 3, 2009 During the recent AES Convention in New York, I attended a panel discussion entitled “Practical Advice for Wireless Microphone Users,” chaired by James Stoffo. The panel included representatives of three top wireless microphone system manufacturers, including Joe Ciaudelli of Sennheiser, Karl Winkler of Lectrosonics, and Douglas Totel of Shure. Stoffo has previously chaired panel discussions at AES that concentrated on large-scale wireless mic installations and applications such as the Super Bowl, but this year the focus was on the “typical” wireless user – a good move. The discussion began with a look at determining operational requirements and expectations, such as how many channels might be needed, the form factor of transmitters, RF power, etc. Some smart comments were offered by the panelists about providing a reality check to potential clients or customers about their expectations, with Ciaudelli making the point that “if it doesn’t need to be wireless, use a hard line” in addressing an example of a drummer requesting an in-ear system. Focus then shifted to antenna types, including dipole and directional types, with Stoffo also noting helical antennas can help in avoiding the problem of antenna orientation, since performers tend to move around and hold transmitters in various positions. The designs of Sennheiser and Professional Wireless Systems (PWS) helical antennas were compared, with a general conclusion that the Sennheiser unit is better suited for wider coverage applications while the PWS unit is better suited for longer range applications due to it’s narrower angle of coverage. The need, or not, for RF amplifiers and/or amplified antennas was also covered, with the clear point made that boosters are needed only to overcome long cable runs rather than to “get a stronger signal”. Coaxial cable loss was discussed in this context as well, with the recommendation to lean toward low-loss coax cables like RG213 and 9913F. It was also recommended to keep IEM transmitter antennas as far away as possible from rack receiver antennas to avoid overloading the receivers. Read the rest of this post 1 2 Comments Leave a Reply Cancel reply Your email address will not be published. Required fields are marked *Comment Name * Email * Website Henry Cohen says “Stoffo has previously chaired panel discussions at AES that concentrated on large-scale wireless mic installations and applications such as the Super Bowl, but this year the focus was on the “typical” wireless user - a good move.” The “typical” wireless user concept was actually brought to fruition by Jonathan Novick and Bob Lee at the 2008 convention in San Francisco for which they were the Live Sound co-chairs. Mac Kerr and I thought it prudent to continue that theme for the 2009 program. “Coaxial cable loss was discussed in this context as well, with the recommendation to lean toward low-loss coax cables like RG213 and 9913F.” RG213 is not considered to be low loss. Whereas it has less loss than RG58 due to it’s larger center conductor, it has more loss than 9913 (or 9914, LMR400, RG6 or RG11); about 6.3dB/100’ @ 600MHz for the single braid RG213 versus about 3.3dB/100’ @ 600MHz for the double shielded 9913. Tagged with: AES Mike Wireless Panels RF Wireless Systems · all topics Subscribe to Live Sound International Subscribe to Live Sound International magazine. Stay up-to-date, get the latest pro audio news, products and resources each month with Live Sound.