Whit Norris, C.A.S., and several other noteworthy production sound mixers recently ran a variety of wireless audio mixing tests using the Kaltman Creations Invisible Waves CPAntennas. The testing was handled in a film production type environment to see the results.
Norris’ background includes recording production sound for such films as Fast and Furious 7 (currently in production), Anchorman 2, Hangover 3, Identity Thief, Fast Five, American Reunion, The Crazies, Whip It, Jay and Silent Bob Strike Back, and Dogma
The following are his and his colleagues’ findings:
While testing antenna efficiency during filming we had the opportunity to use both the Invisible Waves CPAntennas as well as Lectrosonics antennas and see a comparison between the two products.
We used my recording cart with 2 Venues programmed to the same block 21 channel.
The first Venue used the 2 Lectrosonics ALP650 antennas (with a list price of $735). The second Venue used the 2 CPAntennas. The audio was routed through my mixer then to the Deva where the headphone matrix was set to have the 1st Venue with the Lectrosonics antennas in the left ear and the CPAntennas with the 2nd Venue in the right ear.
I do want to point out that we were testing “apples and oranges.” The Lectrosonics ALP
650 is a high gain antenna (Log Periodic Dipole Array or LPDA) while the CPA (at a list price of $290) uses circular polarization technology. The Lectrosonic antennas are generally considered the most popular in production sound.
We tested the Lectrosonic SMQV Transmitter attached to the ankle as well as in the pocket. In most cases the Lectro antennas had a greater reach as far as distance. But both antennas performed over the same distance as far going inside a house and the antennas stayed outside. They also performed the same when walking around the corner or behind a building.
We did notice that the CPA’s has a wider pattern than the Lectros when we were off axis, which can be a plus. Here is where the CPA’s really outperformed the Lectros. We did a few tests with cars…transmitter in the visor and moving past and away from us. The CPAs held much better than the Lectros. There was a very big difference in the signal consistency and less drop outs over greater distances.
I have heard from several mixers who use the helical type antennas that work best with moving cars, process trailer. If you are doing car work/process trailer I would recommend the CPA’s.