I just received my Sennheiser G2 dual pkg from B & h, and I have a few complaints that are making me question whether to return it or not.

I also bought the metal mounting brackets to mount it on the mounting bracket on my Canon XL2. The receivers slip tightly into the felt lined metal enclosures, (they sound like they're getting scraped all to hell every time but i've checked and found no scratches)

They sound great, i've read great reviews. Everything sounds fine right? Here's the deal breaker! Sennheiser in all their wisdom decided to put the on and off button inside the folding metal lid. This sucks! Because If i'm at a gig and tun the receivers off to save battery power, i have to yank the receivers back out of their cradles, open the flaps, power them on! This is terrible! What if I'm shooting a wedding and i have to turn them on in a hurry. I'm hosed! I had no way of knowing this before I ordered them. How come nobody has complained about this?

Now I'm irritated, and under pressure, (short B&H return policy) to return them and wait 2 weeks to get something else. But what? I've looked at the Audio Technica 1800 series kit. i like that it has a dual receiver. People say its has true diversity. What does this mean? Why would I need that?

Does anyone have any opinion on this situation? I'm going to be shooting a lot of live events. But I will also be shooting commercials and short films. I just don't want to get hosed fiddling with my gear when I can calibrate ahead of time, turn the unit on and off with a flip of the switch. I don't want to be caught fiddling with the housing when i'm supposed to be shooting.

Any help?

Dear Jon,

It is not as bad as it seems.

If you get good batteries, such as Energizer NiMH rechargeables, you can power the Sennheiser G2's for hours. Way longer than you can shoot.

So, if you need to turn them on and leave them on, do so.

Hmm, But I keep eying the Audio Technica 1800 and see that its one housing, with LCD screen on top + on/off switch. AND its true diversity. For the same price!

I just can't find any reviews on the Audio Technica 1800 system

Better to have it on and stay on. I like the fact that talent or client cannot turn them off.

I was extremely pleased when I purchased my Sennheiser G2 unit and found out the on-off button was hidden under a cover. no accidental turning off!!

So you guys just leave them on all the time during a gig? The only way i can check battery is the pull it out of camera mount and look at them. Pretty much impossible during the middle of a shoot.

Granted, theres no accidental turn off. But being able to flip them on while shooting seems like a necessity. Am I just crazy?

Dear Jon,

The batteries last a long time. I have never even came close to running out of battery power. I charge up the rechargeables the night before.

Shoots that last over five hours usually have a break. You can then check the batteries and put in fresh ones, if necessary.

You will learn how long the batteries last, or even run a test yourself.

If you have a break of 30 minutes or more, I would turn them off.

It is far better to have the on-off switch under the cover so that it does not get accidentally turned off.

If it were me, I'd return it and get the AT. The receiver is much bigger and heavier though, if that's an issue. I actually like that the AT receiver is heavy because it helps balance my XL2. Off button is very easy to get to on the AT. For me though, diversity makes it the clear winner, plus, they make a dual receiver version which I can't say enough good things about. It's a battery hog though.

Sounds to me you might have the right system but the wrong mounting bracket. But maybe that`s too easy and you are just looking for a way to justify exchanging the Sennheiser for the AT. I love my G2, btw and I use the hot shoe mount that came with it. Or it goes into my mixer bag, works both for me.

Hmm, But I keep eying the Audio Technica 1800 and see that its one housing, with LCD screen on top + on/off switch. AND its true diversity. For the same price!

I just can't find any reviews on the Audio Technica 1800 system

Done.

Regards,

Ty Ford

Audio-Technica 1800 Series Dual Channel Camera-mount UHF Wireless System
Ty Ford
Sticking one wireless receiver on the back of a camera is fairly common for run and gun. If you need two, Audio-Technica’s new 1800 Series Dual Channel Camera mountable UHF wireless system deserves a look. Although single receivers are available in the series, the new ATW-R1820 dual channel receiver is a significant change in wireless receiver technology.

RECEIVER FEATURES
The ATW-R1820 dual channel receiver contains two separate full diversity receivers. That’s a total of four RF front ends in one case, all using the same two BNC-mounted stub antennae. It also has an auto-scanner and onboard audio mixing features. The receiver kit includes a snug cloth holster with a metal clip that can be used to attach the receiver to a belt or to the back of a battery box. The bottom of the holster is open but fitted with straps to allow the short mini-XLR to XLR cables included with the kit to be attached to the receiver audio outputs. BEC group (www.thebecgroup.com) also
makes a receiver box that locks onto various camera battery lugs into which the receiver fits. The receiver weighs one pound six ounces when loaded with six AA batteries. While the receiver case is metal, the battery door is plastic and detaches completely from the body. That makes it one more thing to keep track of. Fortunately, six AA batteries provide nearly six hours in dual receiver mode and almost 10 hours in single receiver mode, so battery changes shouldn’t be required as often. The receiver has a small, four bar battery life display in its LCD window. The receiver also has an external power jack to accept 12 V DC, 500 mA from a camera or other external source. The top of the ATW-R1820 receiver hosts the two BNC antenna connections, power/audio peak LEDs for each receiver, a power switch for internal/external power for one or both receivers, controls for changing frequency and operating the auto-scanner and antenna switching status lights.

The bottom of the two-channel receiver is relatively busy. There are two mini-XLR outputs, A and B and a switching matrix. You can send the output of receiver one to both outputs, so it feeds both A and B mini-XLR outputs. You can route receiver one to output A and receiver 2 to output B so each are on separate tracks for split track or stereo recordings. You can route receiver one and two to MIX which makes a mono mix of both channels available to both outputs. Two small pots on the bottom of the receiver are
used to adjust the levels of the individual outputs or create a two channel mono mix of the two mics.

MIXING RECEIVERS TO OUTPUTS.
The receiver’s mixer allows some interesting possibilities. If receiver one‘s is set to output A and receiver two is set to MIX, receiver one is audible on both outputs and receiver two is audible only on output B. If receiver one is set to Output A mix and receiver two is set to Output B 2, receiver one is only on the left channel and receiver two is on both A and B channels. Depending on how the receiver is mounted, you might want to tape over the mixer controls after setting them to prevent accidental changes.

One of the features I like best about some of the AT receivers is the stereo mini jack right on the receiver that lets you listen to the audio before it gets to the mixer or camera. In this case, it let me sort out which mic was going to which output. There is also a monitor level control which has plenty of gain to feed a set of headphones. There was a difference in the audio between what my Sony MDR7506 heard from the stereo mini jack directly from the receiver and the audio passed from the receiver’s balanced out-
puts to my Sound Devices 442 mixer. The main outs were clearer, making the receiver mini jack output sound dull by comparison.

BODY-PACK TRANSMITTER FEATURES
The ATW-1801 body pack transmitter (and ATW-1802 plug on) each run on two AA bat- teries, a departure from 9 VDC operation. The transmitters, as with the receiver, may be ordered to operate on either of two frequency bands; 541.500 MHz-566.375 MHz or 655.500 MHz-680.375 MHz. There are a total of 996 frequencies per band in 25 kHz increments. The phase lock loop system uses FM modulation with +/- 10 kHz deviation.

Each transmitter can be adjusted for 10 mW or 30 mW output. RF output obviously determines battery life. Both transmitters have LEDs that show green when powered up and red when powered but muted. These LEDs blink to indicate low battery. There is also a small, four bar display in the LCD window of each transmitter that indicates battery life. The mute and
power can be locked either on or off. There is no noise when switching from mute to on. Powering down the transmitters, however, does generate a small click.

I also found some situations in which there was enough RF in the air to allow some unpleasant noise to escape the receiver even after the transmitters were turned off. A small but readable LCD screen and can be toggled to show the status of the features of each transmitter. When the transmitters’ SET buttons are pushed, the LCD becomes backlit; enough to see in the dark. When in MUTE, “mute” in very small letters appears on the transmitter’s LCD display. Both transmitters have sliding panels that cover the adjustment controls to prevent accidental status changes. The panel on the plug-on
transmitter has a hole that allows you to turn the transmitter on and off, even when the panel is closed.

The ATW-T1801 body-pack transmitter is slightly smaller than a box of Marlboros and chews up a pair of AA alkaline cells in eight hours at low power and six hours at high power. That specs out to 160 mA and 180 mA current consumption, respectively. The body-pack has a switchable input with low-Z input for mic or high-Z musical instrument pickups and also makes available a small bias voltage, but not enough for Phantom Power. Input sensitivity is adjustable in four steps from -6 dB, 0 dB, + 6dB and +12 dB, with a default of + 6 dB.

The antenna on the body-pack transmitter unscrews. The microphone connector is spring loaded, locking, four-pin Hirose-type connector. Pulling the sliding outer shell of the connector releases the lock. The spring clip for hooking the transmitter on a waistband or pocket is designed so that it can be reversed; allowing the mic to be mounted in either of two vertical orientations. The transmitter case is made out of high impact plastic. The battery hinged door is a little hard to get open if there are no batteries to pop the lid.

PLUG-ON TRANSMITTER FEATURES
The ATW-T1802 plug-on transmitter duplicates the features of the body-pack transmitter with a few exceptions. It provides 12 V DC Phantom Power, but doesn’t have a high impedance instrument input option. The Audio-Technica AT 4073a worked very nicely with the plug on. It’s high sensitivity may not be what you want in extremely high SPL environments, but it feeds the plug on an impressive signal. A Sennheiser 421 dynamic mic, while less sensitive, also worked well.

IN USE
The auto-scan feature on the receiver needs some work. Its first scan ended up in the middle of a used NTSC channel in town with a transmitter about six miles away. At that frequency, range was limited to about thirty feet. After checking a chart and choosing a more open frequency, I walk tested both transmitters running high power (30 mW) with the receiver in dual mode and got about 50 yards before taking soft hits on the plug-on and 70 yards with the body mic. I did have some unusual range reduction problems on
a rainy day.

On subsequent days, I got more than 50 yards with the body mic and 30 yards with the plug on with my body between the mics and the receiver with both transmitters and receivers working; about ten more yards when the antennae were in the clear. The plug on, one day, went a good seventy yards when held vertically and in the clear.

Using two antennae for two full diversity receivers in the same box can be expected to reduce range to some degree. It’s a simple trade off; some range for operational flexibility. So while you may not break any long distance reception records with the Audio-Technica 1800 Series, partnering two diversity receivers and a mixer in one box does give you a lot of operational power.

SUMMARY
Navigating the menus to make changes was easy after I had used the system a day or so. For the ENG/EFP market, where having two channels of wireless strapped to the camera is increasingly useful, the Audio-Technica 1800 Series brings a lot to the table, especially at its price point of $1795. You may or may not want to use the mixer features on the receiver, but having them does provide options. Audio-Technica sells the 1800 Series in three different sets; a receiver and two body mics, two plug-ons or a body mic and a plug-on. The only things on my wish list would be a strapped pouch to hold everything and, of course, 48 V Phantom Power for the plug-on.

Ty Ford is on special assignment from Radio World and Pro Audio Review. He may be reached at www.tyford.com.

The receivers and components are also available for sale separately.
Contact: Audio-Technica U.S., Inc., 1221 Commerce Drive, Stow, OH 44224. Tel: (330) 686-2600; Fax: (330) 688-3752; Web: www.audio-technica.com
©*Copyright 2007 Technique, Inc. 8/07

Oh, just want to add that I'm not bashing the G2. It's lovely. Having used both, I just like the AT better for a number of reasons.

I like the idea of redundancy.

If the AT 1800 receiver fails, you could lose all of your receive capability.

If one the Sennheiser G2 units fail, you lose just one of two receivers.

This is not a big issue as I think both of the units are of high quality.

In rare cases, when I have two transmitters far apart in a scene, I will set one receiver nearest the appropriate transmitter, then set the other receiver nearest the other transmitter. Then I run XLR cables to the mixer.

The idea is to keep the transmitters and receivers close enough together to receive a good signal. If both receivers are in the same unit, then you lose this option. (But remember, the need for this option is fairly rare.)

You don't say if you have some kind of external, additional, hard drive-based recorder. If not, then the longest you're recording with your camera is slightly over an hour, so you're having to stop at that point anyway. But as the chaps above say, your transmitters and receivers will run much longer than that on fresh batteries, quite probably the whole day, even on rechargables. Just make sure they're freshly charged before heading out the door. Keeping a full set of non-rechargables at hand is a good idea for emergencies, as many brands will last easily 5 years before corroding.

Real world use of the AT1800.

I've been using it all year long. 1 body pak (just got a 2nd) and 1 plugin with a hardwired lav mic. I've used it with my SM58 and SM63 (love my 63). Both lavs are Countryman EMW shelved response mics.

For typical weddings I run 1 mic with body pak on groom and 1 with the phantom box and plugin on the lectern for the readers and to help pick up the music. Just a side note, my on camera mic is a AKG SE300/CK93 hypercaroid which IMO is pretty much the best thing I've ever used in a church. Anyway, I have the receiver set to channel 1 and channel 2 and run the 2 seperate channels of the receiver thru a Y cable to channel 2 on my 170 (the oncamera hyper goes to channel 1 of the camera). I have the channel 1 of the receiver set to the mic that's on the lectern therefore I can leave it on to help capture 2 tracks of the music and once the bride is passed off to the groom I can switch on the grooms mic (on the receiver of course the xmitter is already on) by simply sliding the switch to BOTH.
Seems complicated but it's not. Let me take it one more step in my setup and then my opinion of the sound quality.
For the reception I use channel 1 only as I have a Sennheiser E604 drum mic set up in front of the DJs speaker to capture the music and I use the hyper for room ambience and get the high side of the music. The E604 gets the lower end very cleanly and without naughty nasty stuff that's not supposed to be there.

Now that's the set up, here's my opinion of the sound quality.
AWESOME!

Yes, I have noticed a little bit of noise during quite times of the ceremony, nothing that a quick application of noise reduction can't clean up 100% in post. Maybe I have the levels set too high on the receiver which is something I forgot to mention before. You have level adjustment capability for both channels right on the very busy bottom of the receiver.

Perhaps it's the mics but frankly I tried the stock AT839 (I believe that's it) that came with the body pak. I tried it just to have a comparasion and while the difference was fairly noticable compared to the Countryman it wasn't a GROSS difference but the Cman mics are fantastic none the less. I love being able to monitor ALL of my audio unlike before using 2 seperate units. I have run the unit on coppertop batteries for well over 8 hours without changing batteries and frankly only once did the plugin xmitter die on me after 5 hours and it was my fault. I THOUGHT I had changed batteries but got distracted (my wife started talking to me about some silly thing - probably money :-))
and I realized when it died I hadn't changed the batteries as I mark the date with a sharpie marker on 1 battery in each unit so I know for sure.
Anyway I love the unit and like I said I just got another body pak and Cman mic for the kit. I couldn't be happier.

Anyway that's my $.04 worth (gotta keep doing like the gas prices)
OO
\_/
Don

well i'm up to twelve units of g2 and bet i use them in the most extreme of conditions and circumstances. the battery life of 2 regular alkaline AA is 8-10 hours. just leave them turned on, they will be fine. batteries are cheap anyway. i have nothing but good things to say about the g2's. for the money you can't do better.

I've got the Sennheisers,off the shelf batteries last around 9 hours at least.

Paul.

Phil Bambridge.

I just noticed that you're from Bristol. So i just wanted to say hi.

Paul.

I like my G2s too and I'm glad they can't get turned off easily.

well if the receivers are on the camera, power them from the camera battery - at least if you have AB or V mount you can.get a power tap cable and put a coaxial connector on it, or Y out and put 2 on. vastly more reliable and economical. in the audio bag they run on the bag's battery system (24V & 12V). I can't recall the last time I used a 9V in a receiver.

if you really must use 9V's, at least get a set of the iPower rechargables from Trew or another pro audio dealer. you'll pay for them quick enough.

Just a word of caution. A lot of the NiMH "9V" batteries are not 9V and we've found the Senny kit will not run with them. Even the AA NiMH batteries are 1.2V not 1.5V although the newer kit does seem happy enough with them.
Also be careful that the higher capacity NiMH batteries have a higher self discharge rate than the ones around 2100mAH. Not an issue if you charge them the day before use.

Aside from that we've got around 8 G2 kits and they've been rock solid.
I can't understand why anyone sees making the on/off switch hard to get to a problem. What is a problem is that the mute switch is too easy for the talent to get to.

Dear Bob,

I agree that the NiMH are rated at 1.2 volts.

Fresh off the charger, a good NiMH (Energizer Brand 2500 mah battery will read about 1.40 volts. If you use it within a day or so, it will still read near 1.40 volts. (Note: It is considered best practice to remove the battery from the charger when the charge cycle is complete. If you leave the batteries in the charger, the charger will drain the batteries after a while.)

I read about 1.56 volts on fresh non-rechargeable alkaline batteries.

So, you do lose a little in voltage, but, just as you say, the Sennheiser G2 units work very well with these batteries.

Switching from the 9v batteries that the G1's used to the AA's in the G2's allows us to use these great, low cost rechargeable batteries while getting great run times.

Aside from that we've got around 8 G2 kits and they've been rock solid.
I can't understand why anyone sees making the on/off switch hard to get to a problem. What is a problem is that the mute switch is too easy for the talent to get to.
In the long standing tradition of suggesting something five times the price of the equipment being talked about, if you need to turn the transmitters on and off, I highly recommend the Lectrosonics SMa or SMDa unts together with the RM remote control to turn them on and off and make other adjustments:
http://www.lectrosonics.com/wireless/wireless.htm

The RM is only $580. The SMa transmitter and a 401 receiver can be gotten for only $2465:
http://www.bhphotovideo.com/c/product/416113-REG/Lectrosonics_401SM29_400_Series_Wireless.html
(The 411 receiver is a little more.)

[This is a very good unit. If any one has an SM transmitter they want to sell cheap because they are upgrading to the SMa or SMDa, please let me know.]

Aside from that we've got around 8 G2 kits and they've been rock solid.
I can't understand why anyone sees making the on/off switch hard to get to a problem. What is a problem is that the mute switch is too easy for the talent to get to.
In the long standing tradition of suggesting something five times the price of the equipment being talked about, if you need to turn the transmitters on and off, I highly recommend the Lectrosonics SMa or SMDa unts together with the RM remote control to turn them on and off and make other adjustments:
http://www.lectrosonics.com/wireless/wireless.htm

The RM is only $580. The SMa transmitter and a 401 receiver can be gotten for only $2465. (The 411 receiver is a little more.)

[This is a very good unit. If any one has an SM transmitter they want to sell cheap because they are upgrading to the SMa or SMDa, please let me know.]

As far as rechargeable, Thomas Distributing is a good source and here is a 9.6 volt:
http://www.thomas-distributing.com/mh-96v230.htm

Here are some similar batteries:
http://thomasdistributing.com/shop/-nimh-rechargeable--9v-nimh-batteries-c-122_104_109.html

I've been using the AT-1800s for a couple of years and they've proven reliable.

As mentioned in the review it's possible to scan into a busy channel. And it can be frustrating to find a clean one sometimes. But that can also be a problem with any other wireless units that cost less than a Lectrosonics setup.

Good point about redundancy. But even in the absence of a working wireless, there should be a plan B. Mine is a wired mic. Not a great option but workable in a pinch.

Eventually we'd like to get a second unit and a recorder as there are times when having 4 wireless lavs would help get better audio.

Battery life with the AT-1800 is pretty much what is claimed by the literature. It takes six batteries to run the receiver and four to run the two bodypacks. That's 10 batteries per 6-hour stretch. So if you're doing a long day, you'll need at least 20 AA's.

I just keep that in mind when out in the field. I have to keep everything "on" and ready in the type of work I do. You just never know when the fish will strike. It's not easy being on alert for 9 hours but that's how it is sometimes.

Just thought I'd share my absolute misery with my 2 sets of Sennheiser G2 ew-112's.
Just like my previous 2 weddings, the wedding I shot yesterday had some interference/dropouts etc. Nowhere near as bad as the first but still unacceptable. I'm no audio expert but I have tried different frequencies, scanning for free channels etc.
Everything seems fine then when it really counts it starts to falter. BOTH of them falter so it's unlikely I have faulty units. I'm running out of options and I shouldn't have to 'wonder if my audio will behave itself this time' at every wedding. Crazy.
I'm wondering if anyone else is having so much trouble with their G2's and I've started to look at the Audio Technica 1800 system. Could this be my saviour or just more money down the pan?

Also, I've noticed most of you in the US seem happy with the Senn G2, so perhaps this is a UK specific problem?...have tried looking into frequencies but like I said I'm no audio expert!

Dear Damian,

Please let us know what frequencies that you are using. I am wondering if you are using two frequencies that are close together.

What is the distance from the transmitter to the receiver?

Do you have the antennas oriented in a similar direction, such as both up or down, or is one up and the other horizontal?

After scanning for an open frequency for one unit, do you then leave the first transmitter on and then scan for a second open frequency?

Are their guests close to you, or close to the transmitters or receivers that have cell phones on? I realize that this is almost possible to control, but may be the source of your problems.

Dan beat me to the punch and asked all the right questions.

I noticed you said ew-112's, which have the mains powered rack mount diversity receivers.

Given that these receivers have even better reception characteristics than the EW G2 "bodypack" units, I'm convinced there is a suitably large dose of "operator error" going on here, especially if two entirely different units are affected.

I've used the G2's at up to 200 METRES (admittedly over water and not an obstruction in sight) and got good sound without dropouts.

The most obvious thing I can think of is mutual interference.

From my reading of the Sennheiser manual for the G2's, each bank of 4 frequencies has been tested to ensure that none of the 4 will interfere (under normal operating conditions) with either of the other 3 in that bank.

If you're using two systems, try choosing each units operating frequency from the the same bank, not different banks.

Works a treat with my two systems - having said that, NZ doesn't have the radio clutter so prevelant in the States and the EU.


CS

Wrong frequency block, cell phones, Nextel Phones, iPhones.

Regards,

Ty Ford

I had all manner of problems with some Sony radios, and was about to go with the G2 kit. Had a chat with a sound recordist chap I know who sells both and he suggested the AT1800 range, although he said there was a fault with early models that caused some alising in the audio when both channels were used.

Long and short of it, he lent me a kit (2 x Tx, 1 x Rx) and having tested them, I bought them. They perform well both on the back of my DSR-450, and also through a mixer. I have another AT radio kit as well and that has never given any problems.

Ty - thanks for the review - spot on as usual!

Hello Graham,

Thanks for the hat tip. :)

Regards,

Ty Ford

Thanks for the replies guys.
Chris, just to confirm I am using the bodypack receivers and transmitters, it says on the box ew112-p camera set.
I'll try to answer some of the questions and suggestions:

I have both receivers placed side by side on my belt, antennas pointing up.
They are both connected via the XLR leads to a Zoom H4 strapped to the opposite side of my belt.
I use Bank 8 for both receivers which contains the licence-free frequencies for my region. I scan with one for a free channel, then while this is still switched on I scan with the other.
I tried 863.100 on one set and 864.300 on the second set at the last wedding, plus I changed the frequency quickly on one set as soon as I noticed some interference. The trouble is as I'm sure you understand, I don't generally have time to go hopping back and forth messing around trying to strike it lucky with a magic frequency. I have also tried some frequencies from the other banks and everything works perfectly at home, through walls to outside etc.
The transmitters are placed on the groom and father of the bride at different points during the day, again pointing upwards and practically always in line of sight never more then 10 meters away and with regards to a recent ceremony, literally 4-5 feet away LOL.
It does seem to be when people start arriving so mobile phones has crossed my mind, but I thought the licence-free frequencies would have been ok since they are reserved for private individual and enthusiast use? From what I've hastily researched the mobile/cell phones have their own big frequency range. Perhaps standing by the entrance with a bucket and confiscating phones is in order, since there is always one dipstick who dosen't turn theirs off.

I know that I can turn the transmitters/recievers upside down, space them apart, wave them in the air, shout at them, eat them etc. but surely little enhancments like this shouldn't be the cause of such drastically dismal performance at such close ranges.
I know the Senns are hardly the most expensive units, but for me they are certainly not cheap and paying this kind of money, I expect things to just work with minimal fuss.

I'm going to look into what you said Ty, about the wrong frequency block and generally try and do some more research on frequencies around the UK, but like I said a channel will come up free and clean for a while, people arrive...some interference...scan and change frequency again...seems clear...moment when it counts, interference...can't do anything about it now as I'm behind the camera sweating my bollards off. Nice.
Sorry for the rant and long post and I really appreciate your suggestions. ;-)

Damian.

Dear Damian,

Thank you for providing the detailed information necessary to troubleshoot this problem.

At first glance it appears that you are doing everything right.

I feel that the main problem is cell phone interference.

Since you are recording to the Zoom H4, you could place the receivers and the Zoom H4 as close as possible to the transmitters. These could be hidden somewhere.

You could build a little box to hold the receivers and the Zoom H4 so that they would be easy to move.

Do you keep your own cell phone off?

Damian,

I have been in two situations with my AT U 100 where the wireless reception was fine during setup. I walk tested the units and was getting 50 feet solid and didn't even need that.

When the talent showed up and I put the transmitters on them, range plummeted to totally unusable and the receiver was four feet from the transmitter. The bride's worked fine. It was the groom's that was unusable. Fortunately I had a boom ready and I went to boom for him and got it all. The groom was excited, and probably didn't have is cell phone turned off (again.)

The other situation was one guy speaking. Again, during setup I had plenty of range and had worked that room with that right a dozen times before with very few problems. I put the body mic on him and reception went to total shit from 8-10 feet away.

I went hardwired and we did OK. He left, and I was able to use the previously malfunctioning system out the room and 100 feet down the hallway. It had to be him.

Some folks think their cell phones are off when they are really in standby. Mine's either on or off.

Hope this helps.

Regards,

Ty Ford

Thanks for the info Dan, Ty. Just like you say, the more I think about it cell/mobile phones seem to be the only thing that offers some explanation and all locations have that in common.
I'm not so keen on the little box to hold the receivers and H4 near to the transmitters, I feel it kinda defeats the object of wireless and I wouldn't be able to monitor. Also it dosen't seem to matter how close I am as I've learned!
I keep my own phone in the car so I know it can't be that.
The registrar/minister/priest etc. already tells guests to switch off phones just before the ceremony. It's just a consistently ridiculous situation. (say that five times when your drunk lol)
I think I've got four options:
1. Keep trying with the Sennheisers, investigating what frequencies here might be best or offer the least chance of interference *yawn*
2. Look into the ATW-1800's, I think they offer different frequency ranges here than the E category Sennheisers.
3. Sell the Sennheisers, scrap wireless ideas, buy two Zoom H2's and two lavaliers to connect to them.
4. Set fire to everything wireless, curse technology and become a monk.

Hi Damian

Is there any chance of uploading a small audio extract that allows us to hear the problem you're getting. I'd be interested to see if they're similar to the odd problems I had with my Sonys.

Cellphones are definitely a problem though - I did a conference recently with my AT kit and one of my team had to confiscate an iphone from one of the presenters! I think it's something to do with the "polling" signal they use. I sometimes get interference on the car radio when my mobile goes. That said, cellphone interference is pretty easy to identify. As Ty says, people think switching it to Silent is OK, but the "polling signal" (if that's what it's called) still happens. the only answer is to switch them off completely during a shoot.

Dear Damian,

When most people hear, "Turn Off Your Cellphones", then think this means to put them on vibrate or in silient mode.

Surprisingly, some people do not even know how to turn off their cell phones completely.

But we need them to be completely off.

Otherwise, their transmissions may cause interference either with your wireless or even the camera's audio when you are not using wireless.

Dan, that is a good point. I guess it's just something that is virtually uncontrollable in a wedding environment. It does make me wonder though how a lot of other videographers seem to get away with clean interference-free audio most of the time, or if this is just a pre-conception of mine and interference is a general headache for most, why do we bother using it at all?
I suppose it's fine for the studio set and controlled location shoots but out their in the 'one chance to get it right' wilderness.....

Graham, I have attached a 30 second file which is a particularly bad segment of audio.
I suppose the phones still have to be connected or stay in touch with the network even when in silent mode etc. in order to keep up to date on its status and whether there is anything about to be incoming. Would a correct analogy be 'always connected to the net, even though your not necessarily downloading anything'?

Dear Damian,

I will defer to others, but your interference sounds like general interference from a high powered transmitter and not cell phone interference.

During this sound bite, was the receiver close to the transmitter?

It sounds like this was at the reception and that their may have been a lot of people between the transmitter and the receiver, but I am just guessing.

Were you monitoring the audio via headphones when this was recorded? If so, did you hear this specific interference?

Recommendations:

1. I would try different frequencies.

2. I would not mount the receivers and Zoom H4 on your belt.

I like to keep the receivers as high as possible. When you have them on your belt and you turn around, then the signal has to go through you, or bounce off another object to get to the receiver.

Your audio clip sounded like there were a lot of people crowded around the transmitter.

Damian

Doesn't sound like the usual cellphone interference to me - more like general interference. I've had something similar when the Tx or Rx batteries have got low...

I've attached a short clip that demonstrates cellphone interference... It's been boosted substantially from the original track to allow it to be heard clearly!

Sorry I can't be more help

Dan, your right it was the speeches during the reception. I was about 6 or 7 meters away and although there was some guests in between, I still had quite a good straight line of sight as I tend to stand sideways to my tripod, so the receivers mounted on the left side of my belt where pointing in the right direction.
The clip was taken from the groom who was standing at the top table, a few people to either side of him.
The squelch setting was on low which is why it dosen't just go mute and I get to hear all that glorious noise. What difference does it make though, mute or noisy, both unusable.
I was indeed monitoring the audio (with beads of sweat running down my face I might add) and that was exactly what I could hear. My headphones were plugged into the H4.
I just find it amazing that I spend a decent amount of money on quality gear and yet it proves to be so unreliable in real world use. Yet, DJ Wannabe at the local bar gets great audio every week with some crumby two bit no-brand vhf system.
I'm not sure how much higher I could practically mount the receivers and H4. I did put one receiver on my FX1's shoe at one wedding, but I still got loss of signal so I took it off.

Graham, I've listened to your clip and I recognise that blipping noise that phones cause. So that's not my problem....hmmm. I always have tons of fresh AA batteries and replace them religiously even when there is probably sufficient power in them to last quite a bit longer. So I definitely know it's not that either.

I'll try messing around a bit more but who needs this hassle when your a one-man-band?
I really appreciate the help and suggestions though.
Thank-you.

Quite a few phones generate this kind of interference. I noticed the Nextel phones are especially bad. So bad, in fact, that I even saw it get picked up by a musician's hard-wired PA system at a restaurant!

Maybe it got inducted by the musician's guitar. This kind of interference would normally be experienced from a badly over-driven, heavily amplified and cheap CB radio.

Wow, seems like nothing is safe!
Do you mean that a cheap CB radio could cause this interference to my Sennheiser's or that the Sennheisers are in fact no better than a cheap CB radio in that they are susceptible to it? Hope that makes sense...
How on earth does everyone else cope with this, what is the point in having 'backup' audio, when the backup audio is indeed more reliable than the main wireless audio? Why not just have two sets of 'backup' audio?
In my case I am seriously considering just having a lav going into a Zoom H2 which can be placed in a pocket and a table mounted H2 nearby for backup. All for the same price as my Sennheiser setup, but without as many headaches. The only price for this is the loss of monitoring, but to be honest I've never really needed to adjust much anyhow.
Ideally though, I would still love to use the Sennheiser setup, as I have it sitting here and it is so handy and lovely when it works. Plus I hate the thought of being beaten by this. *sigh*

Yes, we are pretty screwed. :)

I've had cell phones and blackberries get into hard-wired mics.

It's a mine field out there. Some of the industrial market (meeting rooms at convention centers, congressional committee meeting rooms, etc.) have just been overhauled to provide more shielding so they can better withstand the problems of cell phones, nextels and blackberries.

I think the wireless market gear was already on top of that.

Regards,

Ty Ford

Cheap CB radios, especially the ones with amplified power mics that are over-driven, can "splatter" their signal over a wide range of frequencies.

Way back, when my television was getting reception via an antenna, I the picture was being badly distorted every so often. On a hunch, I turned on my own handheld CB radio and found the channel the guy was transmitting on.

His signal was badly distorted. He had a power mic and figured if some volume was good, more was better. So he had it cranked way up, not knowing that he sounded badly distorted. So I politely broke in and let him know he sounded bad. He trimmed it back until he sounded perfectly clear, and at the same time the distortion on the TV went away.

Everybody won.

The interference came from equipment whose operating frequency was nowhere near that of TV.

It's probably similar with cell phones.

I don't know how these cell phones get their FCC approval if they generate RF over such a broad spectrum. The noise gets picked up by other electronic equipment that have nothing to do with radio. Sure sounds like a serious design violation to me!

RFI elimination is a science unto itself, and continues to get more complicated due to the increase in transmitters that everyone seems to now be carrying. In some cases, the transmitter itself is at fault, but in the majority of cases, the RFI results from the receiver reacting to frequencies it is not supposed to. TVs are a good example of this, as are many audio systems.

Turning-off as many of the transmitters as possible will make a significant difference -- it goes a long way toward eliminating, or at least reducing, the intermodulation products and other spurious signals that can occur.

Wrong frequency block, cell phones, Nextel Phones, iPhones.

Regards,

Ty Ford

Ty, you crack me up, to the point, that's funny but you're right, could be any of those things. I have documented my trials with my wireless issues and ended up (after trying lectros on the same frequency) getting a set of sennheiser g2 100s on a frequency block that was contrary to sennheisers chart. My issues are much better, but you still have to watch out for cell phones etc. One suggestion, if any of your wedding party has a cell phone, tell them to turn it off or just don't carry it down the isle.

I've been running theatrical multi-channel radio systems for years and you're making some assumptions based on common sense, but they are wrong!

The kind of problem heard on the link is very, very common. It isn't interference from cellphones, or powerful radio systems or anything like that. It's classic intermodulation interference, normally caused by the choice of frequencies you're using. It's really nasty, difficult to track down, but quite easy to solve.

Firstly, you have decent equipment - the Sennheisers are simple to programme, and will cheerfully operate on a wide range of frequencies, some of which are legal to use freely, some require (here in the UK) a licence issued by JFMG.

The problem is that due to the design of the receivers (not usually a transmitter problem) - when you use more than one odd things can happen. The maths is a bit complex and you need to know some internal technical details of the receivers, but if any of the frequencies in use are mathematically related to each other, and/or the internal frequencies generated as part of the receiver circuitry, then phantom signals get generated, and these have the nasty habit of wiping out even quite strong signals on the input - as in why even being very close in, isn't strong enough and you get drop-outs, as in the recording. You also get that characteristic rumbling sound as audio frequencies mix internally. A Google for RF intermodulation will give you some of the technical details if you're interested.

The solution is to go to the manufacturers web site and they will have lists of frequencies that have been tested to be intermod free.

Only last week I was presented with a rack of 10 Trantec UHF receivers that had exactly this problem. A quick trip to the Trantec site showed lists of frequencies for 6, 10 and 12 channel set-ups. Changing to their suggested frequency plan totally cured the system. The ones picked originally by the supplier were the four 'free' channels, plus some from the regulated ones. They just weren't any good with each other.

Some radio mic channels will stand the chance of being interfered with from TV transmitters in certain areas of the country, and digital TV, squeezed into the gaps is very radio mic unfriendly, but this is unlikely, and sounds a bit like a buzz saw - not a rumble. Signal strength when it falls below the idea is white noise - so varying levels of hiss signify loss of level. Just beware that the intermod products may make level an issue even close in. I like to think of 10m as being a long way. Over that, and signal dropouts are likely. A receiver on the back of the camera, like the popular 112 Sennheisers isn't offering any diversity reception, so if it fizzes once, it will do it again.

Find working frequency combinations, make notes of what channels are useful. Scanning for empty channels really isn't necessary. It will tell you if another channel is in use by somebody else - common in theatrical venues that could be next door to each other, but it's a crude system. In crowded signal areas such as Broadway and the West End, there are much better and accurate devices available to do this. Some of the Sennheisers have a pilot tone system, so scanning for empty channels may not reveal the other user - because their tone may be different or missing and you could 'land' on a already occupied channel and not notice. Also weak signals may not trigger the scan 'move on' feature.

Other tips for maximising signal strength.

Mens inside pockets are handy - but make sure the aerial is not squished up, or pressed hard against the body - 15 stones of person is a nice absorber of RF energy, so a quick turn that places the body between aerial and aerial will be bad news. If the body is sweaty, even worse - salt makes absorption worse.

Radio mic systems are so unreliable that you do need to be careful. I think that operating on the four free channels is a bit risky - the local pub or karaoke will almost certainly be using them. Even if you have to pay a license fee, it's well worth it.

Solid 100% radio systems are possible - but it's the second one in operation that starts the problems rolling.

In my world, it's very common to have somebody whose job is simply baby sitting the things. One set of batteries is still pretty common per show, despite the manufacturers specs suggesting two or three should be possible. Rechargeables are still not common, no longer because of battery life, just because the possibility of re-inserting a nearly flat, un-recharged one is still too high.

Somebody will be listening to them, ready to swap packs, mics and batteries as soon as the clicks, bangs and hisses are heard.

BTW, the noise I was referring to was the one that Graham Risdon posted.

It's a familiar RF noise picked up right before a Nextel phone starts to ring.