Wireless Freq Range?
 

I'm about to get my first wireless lav system (a Senn G2 ENG) and could use a little advice on frequency range.

Senn's 100 series U.S. frequency ranges are:
A: 518-554 MHz (UHF Ch 22-27)
B: 626-662 MHz (UHF Ch 40-45)
C: 740-776 MHz (UHF Ch 59-64)

I've checked on the Senn web site for TV channel usage in these ranges

https://www.sennheiser.com/sennheiser/icm_eng.nsf/root/products_wireless-systems_frequency-check_usa

for a number of U.S. metro areas including Houston, where I currently live. It seems that as a general rule, "A" is the busiest, "B" is slightly less busy but not much different, and "C" is the least used. Still, of the metro areas I checked, none had ALL of the "A" freqs used and only Dallas had all "B" frequencies utilized.

Senn's web site also indicates that the FCC may limit broadcasters to below 698 MHz in the near future, which is where the least-used "C" range is. Since I'm not sure what that would mean to a wireless lav user, I guess this boils down to four questions:

1. If the FCC restricts the "C" range for broadcasters, would this be a good thing for wireless lav users because we could count on using the freqs when the broadcasters couldn't, or would we find our wireless system turned into a paperweight because we wouldn't be allowed to legally use a wireless system in that range either?

2. IF it turns out that "C" is not a good choice, are there any technical pro's or con's to "A" vs "B"?

3. Anybody out there in the Dallas/Fort Worth area using non-diversity wireless systems in that "B" range? If so, any problems with TV interference, or am I over-analyzing a non-problem?

4. Anybody in Houston...what freqs do you use and any problems?

Many thanks in advance for the info and advice!

Cheers

Pete, wish I could give you an answer.... Nothing bugs me much more than seeing a no-response thread...but I've got no answers. Obviously, I'm not in DFW area, and I'm not a fan of the G2 after a short experience with one...

Douglas,

Appreciate you taking the time to respond anyway! I certainly take heed of your bad experiences with the Senn lav, but still want to give the new ENG setup a try ... has both an XLR transmitter and lav mic in one package for a competitive price. If it doesn't work out, I'll be sure to share my experience and probably move over to AT as you've recommended in other threads. I'm still an amateur/hobbyist, so the consequences of "live and learn" won't be too harsh at this time.

A few months ago I did take your enthusiastic advice about the AT897 as my first shotgun and haven't been sorry!

Everyone,

I guess I'd have to assume by the general lack of interest in the topic that most wireless lav users in major U.S. metro areas are NOT having trouble finding interference-free freqs to work on.

If anyone either knows what the FCC is proposing regarding >698MHz and how it might affect wireless users, or has had an experience where they just couldn't find a clear freq to use, please do speak up.

Otherwise, I think I'll stay away from the "C" band just out of ignorance and go with a "B" band system.

Ciao for now,

Pete --

I've been considering the G2 mic, and have many of the same questions you do. Just curious -- did you attempt to contact Sennheiser directly with your questions about the long-term survival of the "C" system?

Not a bad idea, but no I haven't. I wanted to get real-user experience. Gotta be cautious about a commercial vendor rendering opinions on what a government agency may do when it would affect sales of a shipping product, but there might be some worthwhile insight. I'll try to contact them.

I'm still hoping for any comments like, "I regularly use XYZ frequency in ABC city; no problems" or, "Can't find a free freq in ABC city!" or some such! There must be wireless system users out there reading this forum.

I went ahead and ordered the "B" freq range, but it is on a brief back-order until (estimated) next Tuesday, Sep 7th. If I learn anything new before it ships that would point to using a different frequency range, I'll try to change my order.

Otherwise, I'll try out the "B" range and let the community know what happens.

I purchased the Senn 100 ENG kit last April from B&H. I asked them for advice on which freq range to buy and the guy on the phone suggested "C", so that's what I got.

I only used it once since I got it, for a wedding, where it ran perfectly.

I live in the San Francisco area (San Jose). Am I looking at potential problems by using range "C"?

Well, maybe in the future. Haven't heard back from Sennheiser USA -- it's only been a couple of hours -- but I've been digging into the FCC's web site.

THIS MAY BE TOTALLY INCORRECT, just my very shallow impression after very brief skimming of some online documents, so DO NOT TAKE IT AS FACT:

The "C" band (746-776 MHz) has always been the upper channels of the UHF television spectrum...much less used than the lower end of the broadcast TV allocations. The FCC has the intent -- driven by laws passed by Congress in the late 90's -- to reallocate that bandwidth between Public Safety (fire, cops, etc, I guess) and wireless services. No new analog UHF TV licenses are being issued in that freq range. Also by law, however, existing analog UHF stations may continue broadcasting until replaced by a digital TV channel.

I guess because of ongoing debate, the auctions to sell the frequencies have been postponed; they were originally planned as much as 2-3 years ago. It appears that the 3G wireless companies like Nextel and Verizon are especially interested and have been relentlessly pushing to get the frequencies, so when the auctions do happen I'd guess those freq's will fill up fast over wide areas. No telling when that might happen, but it wouldn't surprise me either way if it happened next month, or in 5 years. How those kind of services will affect a wireless lav system...NO idea, although I'd guess the Public Services freqs would be no good.

Upshot (from my LIMITED research)? I think if you have a "C" band device, you probably have nothing to worry about for some time, and maybe never. Since I'm just now buying, unless someone well versed in this advises me otherwise, I think I'll hedge my bets and stick with the "B" range.

For reference, here're some web addresses to the FCC documents I skimmed:

http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-00-5A1.pdf

http://wireless.fcc.gov/auctions/data/bandplans/700band.pdf

http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-04-168A1.doc

http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-04-167A1.doc

The problem would not be the FCC preventing you from using your existing equipment, because that isn't going to happen. The FCC is concerned about high-power transmissions, not a half-Watt transmitter on your mic.

The actual problem might be that at some time in the future, the C-band could get as crowded as the A-band due to the FCC licensing those freq's to other services. But that, right now, is only an "IF", and even then, you won't be any worse off then all the people in the A-band today. And for the moment, the C-band is CLEAN, and is likely to remain that way for quite a while.

If I get 5 years of excellent use out of my kit before having to replace it, it will have done its job just fine.

-Troy

Troy,

Appreciate your comments; seems a pretty reasonable outlook.

I guess the wildcards are WHEN the FCC will hold its auctions for the bandwidth, and IF digital services would have more effect on wireless lav systems than TV (eg more bandwidth per channel). But then it occurs to me that all analog TV will be replaced by digital TV in not too many years, so ANY of the UHF freqs will be at risk of having digital signals on them that might -- or might not -- limit our wireless mics. Only time will tell.

All things considered, I may yet try to switch it to "C" band since that seems to be the most open range for at least a while, if my order hasn't shipped.

Thanks,

Hi Pete --

I really appreciate this thread -- it helped me narrow my choices and make a buying decision. (I need a wireless lav for a job I'm doing next week.) I just ordered a "C" system from B&H this morning. These things are selling quickly, and, like you, I found that they are backordered at several vendors. (B&H had just gotten 3 in stock, and the salesman said he expected they would be gone before the day is out -- so the timing was good.) Thanks again.

<<<-- Originally posted by Pete Bauer : Troy,

Appreciate your comments; seems a pretty reasonable outlook.
-->>>

No problem.

And, Mike: I do work around the Bay Area (weddings, commercials, DJ events, etc.) and I have yet to encounter a problem on the C-band. Remember, too, that there are 32 preset freqs on each band, and you can optionally tune directly to 1440 different freqs, though you do need to have enough room between them if you're using multiple systems. Plenty of folks use the A-band models successfully today, and that is a crowded band.

-Troy

Well, called my vendor and the "B" range version was to be further back-ordered until the 15th, while the "C" range was in stock. Done deal. Should have it Friday and will post my (beginner's) experience with it around the Houston area in a week or two, and later at other locales.

Gotta go ... new XL2 is feeling under-appreciated at the moment!

Just an (overdue) update:

I've used the ENG kit, "C" Frequency range, a couple of times in suburban Houston. I left it on the factory default frequency and simply started using it...no interference, surprisingly clean sound, very easy.

The ability to plug the ENG kit's XLR transmitter into any XLR microphone is a wonderful thing...ANY XLR mic can now be placed anywhere without any cabling.

It also comes with both an XLR and a mini-jack cable for connecting the receiver unit to your camera.

Although I haven't actually had to play with them, the frequency adjustments seem so robust that I doubt that inability to find a clear channel will be a real issue for the foreseeable future in most any location. Should I run into any problems, I'll update again.

Cheers,

My $0.02, I have the Senn. 100 kit (not the newer G2 system) on the B frequency and it works well. I do weddings around the D/FW area, even did one down in Houston and didn't have any drop outs. It's pretty solid.

FWIW, I recently used a Sennheiser EW 300 G2 series outside Boston for a 1 hr training video, and it worked great with no drop outs. I used 745.850 MHz which is in the C range. The mic was on for about 6 hours, and was never more than about 100 feet from the receiver. We were indoors. I liked the large LCD panel on the receiver which would change it's green backlight to red if there was a loss of signal or peaking of the audio. Despite being the first time I'd used it, it was easy to setup and adjust.

I have some Sony and Azden wireless systems that are up on TV CH's 68-69 as well. I have yet to use them for work.

Ed