Running two Sennheiser Evolution G2 units
 

I was wondering if anyone has any experiences using two Sennheiser Evolution G2 wireless units simultaneously. Up until now our crew have been using a boom pole (rode NGT-2) and/or a combo of 1 wireless Senn G2 or Azden mics. We are thinking of buying another Senn G2 wireless system because in some of our run and gun situations the wired boom pole becomes more of a burden and the audio always is much better from the Senn because of the close mic'ing. We are also hoping it will free up the boom op to run 2nd unit cam as we are a team of 3, sometimes 4 including host. The 2nd wireless unit would be used to mic the interview subject.

My main question here though is, it seems there could be a phase cancellation issue with running the 2 wireless mics so close to each other? Perhaps there are some other solutions I have not thought of or someone out there is already doing this?

I use two radio mics and a camera mic all the time you should have no problems, have a listen to the high force or craster items on www.inortheast.tv two G2's with the camera mic as well for GV cover.

Thats good to know Gary. Do you capture sound directly to the camera or a portable recorder? Also are you panning each mic hard left and right or routing to mono?
Are the two subjects who where the wireless mics close (standing next to each other?)

The audio on both films sounds great, I was worried there might be a thinning of the sound when the 2 wireless mics came in close contact.

You will only get phase problems if the mics are wired out of phase, the two G2's used on those films were straight into the camera (an S270 HDV) as two channels and it was actually set to auto gain as well.
I added some high end in post at around 3.6k and rolled off the bass at 120hz to cut down any wind rumble, on the high force film it was very windy but the G2's performed really well. The dialogue was mixed on pro tools in mono with the music in stereo.

Thanks Gary, thats kind of how I was planning on approaching it, sending both mics to it's own channel on the cam and then mixing both to mono in the NLE. - Appreciated!

Try to keep each mic on its own track whenever possible. You can always mix is post but you can't "un-mix" if you've recorded as a mono mix in the field and later discover it doesn't sound quite right. Phase issues and "echo" can sneakl in when mixing them live, although it's usually not too hard to adhere to the rule of at least 3 times the distance between mics as they are from their respectve sound sources when putting lavs on several people. (This is true whether you're using wired or wireless mics. Never, ever, mix lavs and boom together in the field.)

I'm sure you probably already know this, but at the risk of belabouring the obvious, you do know that you can't operate multiple transmitters into one receiver, right? You need a transmitter AND receiver pair for each lav. Keeping the above mentioned 3:1 rule in mind as far as the mic capsules go, there should be no problem with multiple wireless worn by several people standing close to each other from the perspective of the radios interfering, as long as each transmitter/receiver pair is one a separate frequency well spaced from each other.

Hi Steve - Thanks for the additional tips. Anytime we have filmed with a boom and lav together they have been recorded on seperate tracks and mixed in post. Good advice on mic placement and 3:1 rule - will follow that. No probs on the second transmitter & reciever for second mic we are buying another complete G2 system. I have not done a great deal with Lav's in the past - ton's of studio and boom pool stuff but there seem to be several schools of thought about mic placement.

Some like to position it on the chest area and some on the collar, I have seen both on cable TV docs. In any tests I have done it seems the collar sounds more full and natural then on the chest. Do you know what the general consensous is?

Also hiding the mic's tend to be a bit tricky especially with someone wearing a t-shirt as the only obvious place to position is the collar.

Now I am on P2 with an HPX-301 I have four audio tracks so tend to standardise on the following track assignments for on-location work

Ch1-Camera mic
Ch2-Boom (Rode NTG-1 on a pole)
Ch3-Radio mic 1
Ch4-Radio mic 2

I'd go by what sounds best to your ears or achieves the result you're looking for. Most lavs are designed for upper chest but whatever works is what's right. As far as hiding them, first question I'd ask is whether we need to bother. For dramatic work where the audience is supposedly eavesdropping on reality, yes. But for most video work such as interviews or unscripted TV, we've come to accept unobtrusive visible mics and the need to hide it from view is much lessened. To get a chest level mic on a tee-shirt, you could use a vampire clip on the fabric or go under the shirt with moleskin and surgical tape on the skin. For a female, on the inside of the bra in her cleavage.

Thanks Steve, exactly my thoughts - why bother trying to hide it. Mostly our show is an unscripted reality TV / Travel Doc anyway, in some ways I prefer a boom but we are going to try all wireless because of the hassles trucking a ton of equipment around on motorcycles.

For the boom, many use the G2 500 series plug-in transmitter which supplies Phantom power. Of coarse the boom op would want to have some way to monitor, like a headphone amp with an out or through-put.

I dont bother to hide anymore unless its a drama production, if you look at my G2 mics on the video clips I have the stock sennheiser hard windshield on them with a radio shack soft foam wind gag added on top to diffuse any wind or pops.

As for placement chest is best as all omni mics like the G2 ones benefit from a bit of chest cavity resonance that is why lavs tend to sound worse on females as those frontal projections absorb a lot of the chest resonance.

I kid you not! at the top of the rib cage is about the best position and as said for females if you can clip it to the centre of the bra that is best for position.

Thats a good solution, yes our boom op always monitors with headphones as do I as a second failsafe. The senn G2500 is a good consideration, but we are trying to limit boom use unless we have a car as we are a bit hardcore and like to ride everywhere ~

Not sure if random females would like me messing with their bra straps but I am willing to try :)