Issue link: http://digital.copcomm.com/i/757053
C A S Q U A R T E R L Y F A L L 2 0 1 6 61 I have noticed a change in very recent years and even months. We read about the spectrum sell-offs, we read about the white space devices, we read about the fact that, as wireless microphone users, we're all getting crammed and crowded into the same small spaces. Yet it doesn't seem to resonate until we see our impeccable performance compromised as we scan for clear air in certain frequency bands and none are to be found. Then all of a sudden, the 100-yard throw that your wireless transmitter once had, has now been reduced to 15 feet with hits out of nowhere. Reality sets in and you realize that it's happening. The party is over. You have your FCC license, but what will that buy you? I would suggest if you don't have one, get one. However, it is just a piece of paper that says the federal government is acknowledging that, as a professional user, you may transmit signals within a small slice of bandwidth at fairly low power with a specified number of wireless microphones. We're not even asking for that much. We just want to be able to utilize high-quality wireless audio transmission at about the distance of a football field. We're not transmitting high- bandwidth, high-power signals. It's just audio. It's tiny and it shows how valuable wireless air really is. It's a fishable river on public land that you only want to catch a few trout from for your family fishing business, but the government would like to dam it and reap the profits from larger businesses. It's a shame. In a passive antenna system on a sound cart, getting those dipole, LPDA (Log Periodic Dipole Array), or helical anten- nas up high in the air is crucial. I've seen sound carts where antenna risers are only about six feet above ground and I'm always baffled by this. Countless times our own manufac- turers have lectured us on this and we don't always comply. When you learn your own bubble size and have real compari- sons to go off of, you see that altitude is your friend. This September, the Cinema Audio Society hosted a "Parade of Sound Carts" at the Production Sound Pavilion portion of Mix magazine's "Sound for Film" event at Sony Studios (read about the event in this issue). It was an amaz- ing display of sound carts from about a dozen sound mix- ers/comedians who hilariously teased me about the antenna riser height on my sound cart. It won the "height contest" since it raises to about 15 feet in the air. If I could find a cart-mountable light stand that extends higher, I would buy it. No joke! I have found a steep difference in performance since implementing this tall riser on my cart. ANTENNAS IN THE SOUND BAG This is tricky and an unsettled conundrum in a sector of our craft that is growing at an exponential rate. More users are appearing and practicing in this area of production sound than any other sector of our craft and are searching for viable antenna solutions. The Catch-22 is that half-wave antennas are not as useful in the bag as they are on the cart. The beauty of bag-based work is that, theoretically, you are inherently closer to the wireless transmitters on talent, the wireless receivers on cameras or clients and that large- scale antenna distribution systems or amplifications are not needed. So, the same antenna physics apply even if it seems like a good idea to have antenna distribution replace the quarter-wave whip antennas with external antennas mushed in with the sound bag. It appears to be convenient but it, unfortunately, often yields poor results. Antennas want to be set free-floating in the air! When I see a distributed antenna path terminated into receiving antennas that are mushed alongside the sound bag or up against the user's body, I imagine this range bubble getting smothered beyond recognition. You, the sound mixer with a sound bag, are essentially a sack of water. Then, with electronic components strapped to this sack of water spray- ing out additional RF energy. Not a great combination when hoping to have your antennas provide clean RF reception. Luckily, as mentioned (and this is a great example), our pro- fessional tools in the production sound arena are so effective that, often, their misuse goes unnoticed. Here's an acoustical comparison to this RF energy exam- ple: Imagine hugging an accordion player and then wonder- ing why their music sounds muffled. Smothered. Range. Bubble. The solution? I'm not totally sure—yet. Possibly, a bag user mounts their antennas on a light stand riser as well? Not as portable in regard to a run-and-gun style of shoot- ing. Okay, how about a selfie stick with antennas mounted on it? How about a helmet with a six-foot-tall antenna riser BETSO SHARKIE Letrosonics ALP650 Letrosonics APL620