Wireless "frequency sharing? possible?

[Darryn Carroll]

This seems simple but figured I would check with all the experts. I do a video project twice a month at local college. I always attached a wireless lav mic, and now they do also for their PA. If they are transmitting on frequency XXX, If I can locate and obtain a receiver at the same frequency, will this work? Now the speaker only needs to wear 1 lapel mic. (I tried to piggyback off their panel, but for some strange reason they do want me to, their IT guy is not very flexible).

[Gary Nattrass]

Yes you can do that but I would recommend that you use the same type of receivers as pilot tones can vary between makes and types!
I do this sort of thing all the time to feed different recorders and a PA system but note you can not use two transmitters with a single receiver!

[Darryn Carroll]

Thanks Gary, that should have been my real question, can I use 2 transmitters and one receiver if same brand/model/frequency?

[John Willett]

Originally Posted by Darryn Carroll

Thanks Gary, that should have been my real question, can I use 2 transmitters and one receiver if same brand/model/frequency?

To answer this question first - NO - you *must* have at least one receiver for every transmitter and all should be on separate and intermodulation-free frequencies.

Two transmitters on the same frequency "fight" with each other.


To answer your previous question - YES - you can have as many receivers as you like listening to a transmitter. BUT - they really should all be from the same manufacturer and really of the same series.

Many systems use noise reduction companders and equipment from different manufacturers would not work the same way.

As a note - all Sennheiser evolution series G1, G2 and G3 all use the same system (HDX) and the 2000 series use the same system - so are all compatible with each other.

Sennheiser 5000 series, 3000 series and 1000 series use "HiDynPLUS" and are compatible with each other, but *not* evolution systems.

I hope this helps.

[Darryn Carroll]

Thank you, I actually think I screwed up my own question in my second reply! I got it now I think:

2 receivers with one transmitter: YES
2 transmitters with one receiver: NO

And of course should be same make/model/frequency.

[Richard Crowley]

And in more general terms: 1 transmitter with an UNLIMITED number of receivers.
The only difference between a wireless mic bodypack and a broadcast station is the radiated power.

And unless you are an RF geek, stick to using the same brand/model of receivers for wireless mics.

However, If I were doing this gig twice a month, I would work with the venue management to get them to install a permanent "press feed". The guy who runs the sessions may be uncooperative, but he is probably just a hired hand and doesn't manage the operation or venue policy.

OTOH, note that if you take a feed from the house system, you are at their mercy to mic everything you need. Probably safe for a "talking head" lecture, but unlikely to be satisfactory for a musical or drama event, etc.

[Greg Miller]

In fact, if possible, I'd get a split directly from the wireless system receiver, before it goes into the house sound board. That way, no matter what they do with the controls on their board, it won't affect your feed.

On the other hand, what if they forget to put a fresh battery in the wireless transmitter, and it starts cutting out in the middle of the lecture. You will have bad sound, with no way to fix it later. That makes a good point for having your own independent wireless system.

But then if you have two separate wireless systems running simultaneously, you need to be sure that the frequencies are far enough apart that the two systems don't risk interfering with each other.

[Gary Nattrass]

A splitter at the receiver end of things would be a far more secure and cheaper option and one of these will do it and isolate you from the PA system so there will be no hum problems: http://www.bhphotovideo.com/c/product/547632-REG/ART_SPLITCOMPRO_SPLITCom_Pro_Microphone_Splitter_Combiner.html
You could leave it rigged making it easy to hook up each time you do filming.

[John Willett]

Originally Posted by Darryn Carroll

Thank you, I actually think I screwed up my own question in my second reply! I got it now I think:

2 receivers with one transmitter: YES
2 transmitters with one receiver: NO

And of course should be same make/model/frequency.

Yes .