Sennheiser wireless for dual channel solution?

[M. Gilden]

Hey sound guys, got a Q for you.

I've been working on a documentary style project that consists mostly of following a guy on his hikes. I've been using a Sennheiser G2 wireless system with a lav, which has worked out pretty well so far. Spoken audio from the guy is recorded into the left channel on the camera, which I then separate in post and mix with music/atmospheric sound.

But I have something coming up in which I'd like to possibly have a mic on 2 people instead of just one. I may have access to a second Sennheiser mic and transmitter, which I assume can just be set to the same channel that the receiver is using currently. I'm wondering, can one transmitter be set up to send audio on the *OTHER* channel (right, instead of left), that way the camera can catch them both in separate tracks which I can manipulate in post?

 

[j1clark@ucsd.edu]

Hey sound guys, got a Q for you.

I've been working on a documentary style project that consists mostly of following a guy on his hikes. I've been using a Sennheiser G2 wireless system with a lav, which has worked out pretty well so far. Spoken audio from the guy is recorded into the left channel on the camera, which I then separate in post and mix with music/atmospheric sound.

But I have something coming up in which I'd like to possibly have a mic on 2 people instead of just one. I may have access to a second Sennheiser mic and transmitter, which I assume can just be set to the same channel that the receiver is using currently. I'm wondering, can one transmitter be set up to send audio on the *OTHER* channel (right, instead of left), that way the camera can catch them both in separate tracks which I can manipulate in post?

For things RF, given an 'analog' system for transmission, you can not have two transmitters operating on the same channel. I think I recall reading about a dual channel receiver, which is what you need for the two mic+transmitter setup.

For a 'digital' system two transmitters are 'ok' provided the underlying digital transmission system allows for 'interleaving'... which is how Bluetooth and WIFI work. Again, what offerings there may be that use this type of signalling for 'production audio', is not known to me...

What you can do, is have one transmitter and two receivers tuned to the same frequency, to get more reliable reception... but that's not what you are looking for in this case.

 

[M. Gilden]

Poop. I guess that makes sense. I don't have access to a dual channel receiver, unfortunately. Another option is a handheld mic, but I'd like to avoid that for obvious reasons.

 

[Alex H.]

On the lower-cost end, for dual-channel systems, there's the Audio Technica 1800 series. Not great, and though comparable to (slightly lower than) the price-per-channel factor of the Sennheisers they just don't sound as good. Other than that are super-pricey, multi-channel systems that will cost more than a down-payment on a mortgage.

But... if you have access to a second lav and transmitter, why not also to the matching receiver?

The other option: shops like Trew Audio rent Sennheiser G2/G3 systems for a song.

 

[Bruce Watson]

I may have access to a second Sennheiser mic and transmitter, which I assume can just be set to the same channel that the receiver is using currently.

Sorry, bad assumption. The two transmitters must be on different frequencies if you want to use them simultaneously.

I'm wondering, can one transmitter be set up to send audio on the *OTHER* channel (right, instead of left), that way the camera can catch them both in separate tracks which I can manipulate in post?

Absolutely. I do this all the time. Two G3 sets on slightly different frequencies, one receiver records to right and the other receiver to left. My tiny handycam doesn't have XLR inputs, just a stereo 3.5mm plug, so I use a Hosa 3.5mm Y-cable. Works a treat. You get a single stereo audio track that you separate in post, pan each to center. Add another (stereo) audio track for your music.

 

[Exact]

With the Sennheiser you need 2 transmitters and 2 receivers, each operating on independent frequencies, one plugged to your left and the other to the right channel on the camera.

 

[M. Gilden]

On the lower-cost end, for dual-channel systems, there's the Audio Technica 1800 series. Not great, and though comparable to (slightly lower than) the price-per-channel factor of the Sennheisers they just don't sound as good. Other than that are super-pricey, multi-channel systems that will cost more than a down-payment on a mortgage.

But... if you have access to a second lav and transmitter, why not also to the matching receiver?

The other option: shops like Trew Audio rent Sennheiser G2/G3 systems for a song.

Right, logically it would sound like I have access to 2 pairs, but the other transmitter is part of a studio setup where the receiver is built into a rack and connected to a mixer (not portable). I guess I could rent one, but I'm trying to keep my rig as minimal as possible since I need to follow this guy over rough terrain at times. Or maybe I should experiment a bit with a good on camera shotgun and go with a wide lens to get up close. I'll have to experiment.

 

[dishan]

Absolutely. I do this all the time. Two G3 sets on slightly different frequencies, one receiver records to right and the other receiver to left. My tiny handycam doesn't have XLR inputs, just a stereo 3.5mm plug, so I use a Hosa 3.5mm splitter. Works a treat. You get a single stereo audio track that you separate in post, pan each to center. Add another (stereo) audio track for your music.

Wow, so any regular Y adapter for headphones will work for that? I would picture the "blank" channel having some sort of interference or something that wouldn't make it that simple. Like the way two telephones on the same line create more background noise even if no one is talking.
I also have a camera with a single 3.5mm jack for recording audio, and planning something similar. I'll look into renting a second sennheiser set, as I also only have one. I didn't realize you can switch which channel it uses for mono! Is that somethin set in the transmitter or reciever?

Also, I have one scene in the beginning of my project were the host is going to knock on the guest's door, and invites him to come explain something we're going to see in the documentary. Obviously, the guy can't open the door already wearing a mic. Aside from holding a hand-held mic (which I'm trying to avoid for freedom of movement, the guy needs his hands), what other options should I consider for picking up audio from the other person in that scene? Later on I can mic him I guess (unless it would seem weird that he is magically mic'ed later). But for the door shot, should I set up a mic stand with a boom pointing towards the door off camera? I don't even know how possible that will be since I haven't seen the location yet. Trying to plan ahead for any scenario.

 

[Bruce Watson]

Wow, so any regular Y adapter for headphones will work for that? I would picture the "blank" channel having some sort of interference or something that wouldn't make it that simple. Like the way two telephones on the same line create more background noise even if no one is talking.

They aren't sharing a line. But they are sharing a ground. Three wires. Left, right, and (shield) ground. These are wired to tip (left channel), ring (right channel), and sleeve (ground reference) on the RCA plug.

I also have a camera with a single 3.5mm jack for recording audio, and planning something similar. I'll look into renting a second Sennheiser set, as I also only have one. I didn't realize you can switch which channel it uses for mono! Is that something set in the transmitter or receiver?

Uh, no. It simply depends on which side of the splitter you plug it into. If you plug a receiver into the right side, it records to the right channel. If you unplug it from the right side and plug it into the left side, it records to the left channel. You're trying to make this way harder than it is.

 

[M. Gilden]

They aren't sharing a line. But they are sharing a ground. Three wires. Left, right, and (shield) ground. These are wired to tip (left channel), ring (right channel), and sleeve (ground reference) on the RCA plug.


Uh, no. It simply depends on which side of the splitter you plug it into. If you plug a receiver into the right side, it records to the right channel. If you unplug it from the right side and plug it into the left side, it records to the left channel. You're trying to make this way harder than it is.

It sounds like you are describing an adapter rather than a splitter. An adapter would turn a single stereo plug into two mono ones. The hosa cable you linked to above appears to be a splitter, with stereo connections (ie. all three wires, L+R+Ground) at every point. So if two receivers were attached to each female end, both sending out audio on the left channel, they would in fact collide with each other and leave the right channel blank.

Are you perhaps using a different cable than the one linked above?

 

[Bruce Watson]

It sounds like you are describing an adapter rather than a splitter. An adapter would turn a single stereo plug into two mono ones. The hosa cable you linked to above appears to be a splitter, with stereo connections (ie. all three wires, L+R+Ground) at every point.

Correct. Haste makes waste. I learn that lesson over and over.

What I should have posted was this Hosa stereo male to two mono female Y-cable. I would have gotten the number off of mine if I could find it... and that might have lessened the confusion. Sorry all.

I've corrected the offending post also, to lessen the confusion. Oy.

 

[John Willett]

Hey sound guys, got a Q for you.

I've been working on a documentary style project that consists mostly of following a guy on his hikes. I've been using a Sennheiser G2 wireless system with a lav, which has worked out pretty well so far. Spoken audio from the guy is recorded into the left channel on the camera, which I then separate in post and mix with music/atmospheric sound.

But I have something coming up in which I'd like to possibly have a mic on 2 people instead of just one. I may have access to a second Sennheiser mic and transmitter, which I assume can just be set to the same channel that the receiver is using currently. I'm wondering, can one transmitter be set up to send audio on the *OTHER* channel (right, instead of left), that way the camera can catch them both in separate tracks which I can manipulate in post?

No and no.

You must *never* have more than one transmitter on the same channel.

You have to use a separate frequency and a separate receiver for every microphone.

 

[paulears]

Why do you want to combine the left and right like this into one cable? Is it so you can get the mic audio from the two receivers into a stereo unbalanced 3.5mm input? That's the only reason I can think of.

As for channels, use the ones recommended by the manufacturers for multi-channel work, picking channels at random can often produce very unpredictable results.

 

[dishan]

Why do you want to combine the left and right like this into one cable? Is it so you can get the mic audio from the two receivers into a stereo unbalanced 3.5mm input? That's the only reason I can think of.

As for channels, use the ones recommended by the manufacturers for multi-channel work, picking channels at random can often produce very unpredictable results.

Yes, those of us discussing that cable are talking about using in situations that offer only a single 3.5mm input (DSLR, Zoom H1, small camcorder, etc). Obviously if I were using my HVX, I could just pick an XLR plug and go with it.

Any comments on my other question (about mic'ing a guy when he answers the door)?

 

[Steve House]

...
Also, I have one scene in the beginning of my project were the host is going to knock on the guest's door, and invites him to come explain something we're going to see in the documentary. Obviously, the guy can't open the door already wearing a mic. Aside from holding a hand-held mic (which I'm trying to avoid for freedom of movement, the guy needs his hands), what other options should I consider for picking up audio from the other person in that scene? Later on I can mic him I guess (unless it would seem weird that he is magically mic'ed later). But for the door shot, should I set up a mic stand with a boom pointing towards the door off camera? I don't even know how possible that will be since I haven't seen the location yet. Trying to plan ahead for any scenario.

Why haven't you seen the location yet? A scouting trip is part of your preproduction planning, otherwise how do you know for sure you'll even be able to get usable footage there. There may be construction going on right next door with a noise level that makes it impossible to shoot. Better to find that out before you get there on your shooting day so you can find an alternate location.

Well, one option would be to hide the lav on the person answering the door under his clothes. A boomed mic also comes to mind, though not on a mic stand just aimed vaguely in the talent's direction. This is where a boom actually hand-held by a boom operator who aims the mic properly and holds it over the talent's heads just out of frame is the way to go.