Tag Archives: wireless microphone

Why I like Sennheiser G2/G3 systems for everything but talent wireless

sennheiser G3 wireless

Sennheiser G3 wireless microphone system.

Here’s just a few reasons why I love G2/G3 for IFB/scratch track feeds over Lectro or Zaxcom IFB solutions:
– The mini plug input/output is highly compatible without need for custom cables. You can feed a scratch track to  a Red Epic with a standard ipod cable. Transmitter Mic/line input selectable thru tip or ring on the cable. You can hook up to anything with a good set of adaptors. Have you sent audio to a Black Magic camera yet? Non-standard, strangely wired 1/4″ jack inputs, but no problem with a Senn and an ipod cable with a headphone adaptor.
– you can feed  hops and Ifb with same transmitter. 1 less frequency to coordinate.

-Less weight and RF mess in a sound bag. I’d rather carry around a 2 ounce, 30mw G3, than a 1/2 pound, 250mw flamethrower like the Lectro T4.

– I purchased my first set for scratch track hops in 2005. I now have 6 transmitters, 4 plugs, 6 receivers and 15 IFB’s. All purchased on ebay, and on average, less than half of retail. (Many misguided soundies and one-off project users buy these, then dump ’em. )

I’ve yet to have one break.  I’ve replaced many antennas at 5 bucks each, if you can solder well, you’re good.
– huge battery life. 3 days with a pair of lithium AA’s
-audio/rf metering on every unit
-Better range than lectro R1a or zax 2.4 gHz IFB units, owing to  external whip antennas
-transmitter won’t RF swamp a sound bag
-some venues now restricting 2.4 gHz devices as they compete with wifi (Zaxcom IFB)
-super wide input/output audio level settings. It’s easier to set the level on the Senn than dig around on the cryptic Red Epic’s audio screen. So why bother?
-instinctively intuitive to use. Big, understandable, backlit display
-great for feeding video assist, pa systems, or pulling feeds from PA or press feeds
velcro them together for 2 channels, and they are still a very small receiver pkg.
-They’re Great crash wireless for talent- (about the only time I’ll put one on a talent).
-30 mw is low for transmitter power, but as an IFB, the pack is not against somebody’s body.
Instead, it is out in free space on your cart or bag. So no RF absorption from a sweaty cast member’s body.

I’ve have found that the Lectro IFBs are better if your crew needs to change receiver channels frequently to listen to different sound units. WIth Lectro R1a’s, They just push the volume button to cycle thru programmed channels, without needing to look at it. (Don’t know if the ERX can do this).

-Senn’s butt-plug transmitters are also cheap and great for a quickn’dirty wireless handheld for PA or voice-of-god mic for AD’s

On a recent commercial, with one Senny transmitter, I fed scratchtrack to  two Alexas, video assist, client-lounge PA speaker and 15 IFB’s. Excellent range, kinda nice.
-iem headphone amp VERY loud. Even the regular receivers can drive a headphone at +6

-easy to coordinate freqs with internal pre-selects/rf metering, or use the freq finder app.

IEMs and beltpack receivers will also receive acceptable audio sent from more powerful lectro IFB transmitters.

-I could go on. I’ve got buckets of these things.

But I never will use them as frontline talent wireless. They breakup a little at high audio frequencies (sibilant sounds) unless you stay well within the headroom, like half-level.

-By Pete Verrando www.txsound.com

 

Video Blow Torch Transmitter Interference for Wireless Microphones

gx-68 wireless video transmitter swamps wireless mics

The GX-68 Swamping Video Transmitter from Canada.

Imagine yourself listening to your favorite music on an Ipod with some really nice headphones. Maybe those Bose Quiet-Comfort 15’s, my fave on airplanes. They really sound great.

Now imagine you’re at a Skrillex show, 1st row, next to a massive stack of loudspeakers, while still listening to your Ipod with those great Bose headphones. What? Can’t hear your Ipod? You might say you’ve been swamped or more technically, de-sensed. Your headphone audio can’t compete with a Skrillex speaker stack. Bass, highs, no matter. Can’t hear a thing. No matter how great those headphones are, Skrillex’s speakers are overwhelming them.

Skrillex is swamping your headphones. The only remedy is physical distance between you and Skrillex.

lectrosonics, scans, wireless microphones, interference

Various Lectro Scans…Top left- pretty swamped! Bottom right- wide open.

The whole hop affair requires robust, expensive wireless audio systems. But, like my Bose headphones, my fine audio receivers had to share 1st row with the blazing Skrillex video flamethrower, and were de-sensing as a result of the powerful RF eminating from said blowtorch. The receivers have a frequency scan function (Lectrosonics UCR411a), and it was showing complete RF obliteration with the video transmitter switched on. A solid black block, floor to ceiling. When a powerful RF transmitter comes shoulder-to-shoulder with an RF receiver, de-sensing happens. The trans RF overwhelms the circuitry in the receiver, regardless of frequency selected. The only cure is distance.

Move the transmitter 3 or 4 feet away, and everything’s OK! But the only place for the video transmitter and my receivers to live were on the side of the camera. So who’s problem is this? Why mine, of course! Camera and director could not work without the little wireless video system.

No problem, the director says! We’ll just go “hard wire” from sound to camera for the entire week. Dark storm clouds formed over my head, images of water skiing behind camera, with an audio-cable tow rope, inside a wrecked-out house. Outside of interviews and other “tame” shoots, the last time I went hard-wire to camera was probably sometime in 1998.

Cameraman: Works great at home, he says. You can take the camera home tonight and “work it out.”

Lectro Lectrosonics scan swamped

Another Swamped scan on a Lectro Receiver

So, my 1st day goes down with the cable tether, as the production was in 1st day freight-train mode, and no down time for a little audio troubleshooting. I trudge the camera home that evening to perform the “prep” that should have happened the day before the shoot. On the bench, I learn that the transmitter is tunable from 512 thru 800 mHz. From the internet I learn about the transmitter, specs & how to set the frequency, as camera dept. hadn’t a clue about their little black box. I try different combinations of transmitter and hop frequencies, looking for those that play well together. No go. The video transmitter swamps everything from Lectro Block 21 thru 26 and beyond, regardless of frequency setting.

I try some surgery on the video transmitter’s antenna, running a tightly looped wire around the antenna and soldering it to the BNC shell. This detuned the antenna to the point where it became a less effective radiator. However, this may make matters worse by raising the vSWR of the antenna, which may cause the transmitter case radiate RF, or even burn out the transmitter.

I finally mount the transmitter way forward on the camera, tucking the antenna under the viewfinder, and set it to 800 mHz (channel 69). I mount the audio receivers at the extreme rear of the camera, using Lectro block 21 (520 mHz). Doing a scan, this gets the swamping down to the 50% point on the scan display.

Using 100mw transmitter hops, I send audio to the camera and walk test it in the backyard. Amazingly, no dropouts or hits! The Lectro wireless are robust enough to deliver clean audio despite 50% RF interference levels on the receivers. This is using UCR411a Receivers. I’m not sure I could have accomplished the same feat with the less-robust Lectro UCR401 receivers, or SRa’s, which are the equivalent of 401’s. Looks like camera’s gonna have to lug around a little extra weight on the side!

Regardless, I keep a minimum distance from the camera throughout the week, to make sure those hops were solid. I also ran 24 bit backup audio files on everything. Camera dept. refused to do a free-run sync of timecode with my recorder, something to do with the antiquated notion that sequentially coded files digitize faster. No argument from me. If they need the backup, hello Plural Eyes.

Lessons learned! Good times!      by Pete Verrando www.txsound.com

 

bountyxmtr2

Car-to-Car with Lectro’s SMV

   Recently, I was on a shoot following bounty hunters around a city every night for about 10 days. Both cars worked together, with two hunters in each. Each car had a camera operator inside,  and both “hunters” were mic’d with Lectro SMV’s , transmitting directly to an SRb 2-channel receiver on the camera. 

    Camera mic was on channel 3/4.  Now the fun part–   a plant mic was placed in the car’s headliner dead center, and fed to an external SMv transmitter on each car. Both SMv’s at 250mw full power, and taking 12 volts  from each car’s cigar lighter. Our follow vehicle had two Lectro SNA-600 dipoles mounted about 12″ above the roof on fiberglass poles, feeding a Venue Field inside the van. The Field received the 4 officer’s wireless, & the two plant mic wireless.  

Rubber band pulls transmit antenna away from car to maximze range. Fixed to glass with heavy-duty Velcro.
Transmitter  then covered in gaff tape 
Follow vehicle SNA-600 antennas fed a Lectrosonics Venue Field inside. 


On the road, the follow vehicle could reliably  hear those plant mics  up to 1/2 mile away from the hunter cars-  sometimes more in the countryside!  In the city, we would routinely loose the cars in traffic, but could usually still hear them.   This made for great follow vehicle IFB, & two clear recorded tracks of car interior when bad guys were loaded in the car. 

-by Pete Verrando

mailbag

Mailbag- Lectrosonics SRb versus SRa+ Huh?

From the mailbag!  Keep those cards and letters coming!Dave, from Sydney Austrailia, writes:

Hi.
 I’m considering buying an upgrade SRa (serial # is above 105…)
Are yours upgraded? How have they performed? Do you know if they have the 6 layer board?
“The 80% improvement RF board is 17378-K. The full SRb board is 17378-L”
Thanks
Dave
 
 
Hi Dave!
I never owned 1st generation SRa’s so I don’t have anything to compare, but I’ve heard that range on those early SRa’s was pretty bad. That’s why everybody started buying RF amplifiers and sharkfin antennas to hang off their bags.
Now that the SRb’s are available, those RF amps and Sharkfins will probably overload the front-ends of the SRb’s. Ha ha.
Update: I just took delivery on a used SRa- that is pre serial# 105…  Before I get it upgraded, I want to do some comparisons between it and my post-105 SRa’s,.. Range tests are pretty simple, but selectivity comparisons are difficult to simulate and measure. I’ll probably just take their word on it, and continue to do good freq. coordination.
All the best!
Pete Verrando
Dallas TX
 
Hi Pete
Good to hear about your experience. I’ll test a ‘post-105′ or ‘SRa+’ (as Larry F named it) around town if the dealer will let it out for a day or two. Keen to hear how your comparisons go as well pre and post upgrade.
 
Cheers 
Dave 
Hi Dave!
Today I did a walk test comparison of my  SRa to an “SRa+”. (same block) I used one SMV transmitter and tuned channel 1 on both receivers to the transmit frequency. I first noticed the open SRa 2nd channel (coordinated) was much more susceptible to swamping when the  transmitter for channel 1 comes too close. The SRa+ showed no evidence of swamping on the 2nd, open channel.  
In a walk test, the two receivers were pretty close in range in open air, but when I placed the transmitter inside a vehicle, the SRa lost it entirely, while the SRa+ was showing about 50% signal level. 
 
Cheers! (Except I have a vodka martini in my hand)
Pete

 

The saga continues….

-by Pete Verrando

SRa1

Lectrosonics New SRb Receiver Antenna Distro WTF

When Lectrosonics released their SR, a dual channel wireless receiver, sound mixers seized the opportunity to load unprecedented piles of these receivers in their sound bags.  The SR’s original design, however, and a host of RF interference issues from neighboring gear in their “bags”, left sound guys scratching their heads.
These receivers were supposed to be equivalent in performance to Lectro’s 401 receivers. Except they weren’t. And they were even farther away in RF performance from Lectro’s top line 411a.
The SR receivers were less sensitive than the 401’s, meaning reduced working distance from the transmitters. And in UHF, working distance is not a linear thing. One could have excellent reception at 40 feet, then the signal disappears at 42 feet !
Those guys who invested heavily in the first SRa’s (version with removable antennas) were forced to load their packages down with RF amplifiers and gain-based antennas, to overcome the range issue. Basically, they force-fed amplified signals into the SRa’s antenna jacks. Which creates another bunch of problems, but what the hell.
Gavage for the SRa Receiver
Months later, Lectro re-designs the RF board of the SR, bringing the RF performance much closer to the original claims. The SRb was introduced, and Lectro has a very generous upgrade policy for all those hapless mixers who invested heavily in the SRa.
However, now you have guys with piles of antennas, amplifiers, and combiners in their package. And they are chomping at the bit to plug that mess into their SRb’s.
Now, that the SRb is a more sensitive receiver, and I bet it is not going to like all that amplified RF being force-fed into the antenna jacks.  The SRb is a much-improved design, but physics is physics, and receivers will squawk like a goose destined for Foie Gras when fed too much RF.  Wait and see.
-by Pete Verrando