View Full Version : Wireless Frequency Selection


Roger Smith
February 7th, 2008, 12:22 PM
Hello All,
My name is Roger Smith. I am fairly new to the video business. My associate and I have been filming Lectures at a university in the SF Bay Area for about 2 years. We both have Canon GL2s. My associate has a Sennheiser wireless sound system (EW100G2) and has had no problem with it. I have an Azden VHF unit and get occasional noise bursts. I would like to upgrade to the Sennheiser. My associate and I film together with 2 cameras & 2 audio feeds.

My questions are: Can I get the same Sennheiser system and the same frequency range (A: 518 – 554MHz) without fear of interference from each other? Or should I get the next frequency range (B: 626 – 662 MHz)? I have seen the Seenheiser TV Station License chart, but I can’t tell which frequency range is better.

Thanks for your help.

Steve House
February 7th, 2008, 01:12 PM
You can operate both sets in the same frequency block but not on the same frequency within the block. As to what block is most interference free, your best bet is to consult with one of the local audio specialty firms. Be advised that the whole wireless frequency thing in the States is really up in the air (if you'll forgive the pun) right now as the FCC is realigning everything and selling off blocks of spectrum to various services. Again, a local expert dealer is likely to have to most reliable information about where things stand in the Bay Area.

Mark Holland
February 8th, 2008, 11:55 AM
... My questions are: Can I get the same Sennheiser system and the same frequency range (A: 518 – 554MHz) without fear of interference from each other? Or should I get the next frequency range (B: 626 – 662 MHz)? I have seen the Senheiser TV Station License chart, but I can’t tell which frequency range is better...

1) You should be fine using the same frequency range as your associate, just choose different frequencies within that range. (as stated above by Steve)

2) To insure no interference with your associate's system, you could purchase within the B range, (isn't there even a C range available?) However, if there were ever a time when you both wanted a feed from the same mic, the easy way is to set both receivers up to "hear" the one transmitter. It's something to consider...

As for which frequency range is "better", I personally go with the one least likely to give me interference problems. If your associate's system works fine in your area, that'd be my first clue. You might also ask others in you area for their experiences.

Good luck!

Mark

Roger Smith
February 8th, 2008, 01:28 PM
Thanks, Steve & Mark.

I now feel more confident in making my decision.

Roger

Wayne Brissette
February 8th, 2008, 01:37 PM
1) (isn't there even a C range available?)

There is a C block, but it fails in the 700 MHz range that is up in the air in the US. While you're probably going to be able to use it, I think a lot of people are avoiding it because of the uncertainty. Kind of like Block 27 & 28 of other transceivers (If you ever want a bargain on wireless, it seems there are a lot of deals on block 27 & 28 in the used market).

Wayne

Roger Smith
February 11th, 2008, 01:54 PM
Hi Wayne,

Thanks for your input. I think that I will stay clear of block C.

Roger

Lloyd Claycomb
February 11th, 2008, 09:12 PM
Don't mean to hijack this thread, but I can find the place on the internet that you can find out what frequencies work best in your area. Anyone know off hand? (This is for a Senny G2 system.) Needs to work in Phoenix and Orlando.

Jack Walker
February 11th, 2008, 09:26 PM
Don't mean to hijack this thread, but I can find the place on the internet that you can find out what frequencies work best in your area. Anyone know off hand? (This is for a Senny G2 system.) Needs to work in Phoenix and Orlando.
Sennheiser USA Frequency Finder-- Go here and click on your state:
http://www.sennheiserusa.com/newsite/mat_dev/frequencyfinder/Freqfinder-ew.asp

Lloyd Claycomb
February 11th, 2008, 09:36 PM
Thanks.

Is there a general consensus on what the best overall frequency is in the USA? Is there one that seems to work most anywhere?

Allen Green
February 11th, 2008, 09:50 PM
If you purchase the Senn's from a dealer like Coffey, Trew or Location Sound they will usually help you choose by checking for you before you buy to make sure the Freqs. are clear in your area. I deal with Trew audio and I call them when I need help. I bought my Lectros from them and we worked together to find freqs. that would work in the several cities that I work in.

Steve House
February 12th, 2008, 05:54 AM
Thanks.

Is there a general consensus on what the best overall frequency is in the USA? Is there one that seems to work most anywhere?

Because wireless mics work in and around the channels used by other services and the frequencies assigned to those services are all over the place in different parts of the country, there really is no one size fits all. And to make it even more difficult, the FCC is auctioning off large parts of the spectrum to other users and realigning everything as analog TV is phased out. From what I gather, any frequencies above 692MHz are in real state of flux and very likely will become unusable in a year or so. Location Sound has posted Lectro's take on this here ... http://www.locationsound.com/proaudio/ls/rfspectrum.html

Lloyd Claycomb
February 12th, 2008, 02:34 PM
I just read that whole link. I think they're trying to paint it in the best light possible, but the whole thing screamed, "we don't know!"

I need to buy 3 G2s, but they're not cheap if they can only be used for one more year. Maybe I just do wired for now and see what happens.

Wayne Brissette
February 12th, 2008, 02:54 PM
I need to buy 3 G2s, but they're not cheap if they can only be used for one more year. Maybe I just do wired for now and see what happens.

You have two choices as I see it. Either stay away from the C band (block 27 & 28) or go wired. The problem is really only the first option makes sense if you're trying to give talent room to move about or the shot is so wide that you can't get a boom to cover it.

I do agree with you, Larry from Lectro pretty much has scratched his head and said they don't know. But at least he is being honest, because I'm really thinking that at this point that C, Block 27, and Block 28 will continue to work. However, finding an open frequency might simply take more work.

Wayne