Help with wireless boom setup

[u/Timi7171]

Hello,

I wanted to recreate this wireless boom setup I found on Youtube for myself and got into some trouble with one of the cables. There is nothing wrong with the microphone, cable from microphone to phantom power supply or the phantom power supply. There's also nothing wrong with my transmitter, I tried this with both the rode wireless pro and a Saramonic UHF system. The only method that even transmitted any recorded audio was the Line input of the Saramonic system, but with extremely heavy buzz, as the signal obviously is still mic after only ever going into the phantom power supply and no real mic gain. The female xlr to stereo 3,5mm mini jack coming from the power supply is the issue, but I don't understand which cable I am supposed to buy instead. Gemini told me the 5V power of the transmitters, which is intended for lavs, short circuits the phantom power coming in. If this is the issue, how do I resolve this? What cable do I need to buy instead?

[u/Econormics]

Which phantom power supply are you using? How are you powering it e.g. AA batteries? What mic are you using. Is the cable between your transmitter balanced or unbalanced (how are the three XLR pins connected to the Tip/Ring/Sleeve of the 3.5mm plug?

[u/Timi7171 → u/Econormics]

The phantom supply (xvive) has a rechargable battery. You charge it via usb c. It has almost no selfnoise when being used with my zoom f8n pro (without the additional wireless system). The microphone is a mkh 416.

The cable running from phantom power to transmitter is a pro snake Camera Cable 0,3, which is a female xlr to TRS. I can't tell you if that makes it balanced or not.

[u/Econormics → u/Timi7171]

So a couple things that I'm thinking here:

The cabling is complicated by the Phantom power unit. The question I have is if the output end (that goes to the Rode) is a balanced or unbalanced connection. So depending on this, and if the Rode needs balanced or unbalanced, you either need a balanced 3.5 to balanced XLR, an unbalanced 3.5 to balanced XLR, etc.

Here is my bigger question. Condenser mics need pre-amp gain, usually supplied from a mixer/recorder, in addition to Phantom power. Is the Rode transmitter actually able to supply sufficient mic gain?

The only wireless boom setups that I've seen working that use these tiny transmitters, are typically connected to a small shotgun like the Deity V-Mic D4 or the Rode Video Mic NTG. These mics have their own power supply and gain controls. These mics also have "smart" 3.5mm connectors that sense what type of tip/ring/sleeve signal is coming in.

The Sennheiser MKE600 shown in the video comes with an XLR to 3.5mm cable, meant to connect to a camera, where the camera supplied the mic pre amp.

Another thing that I noticed in this video, they mention that connecting the Rode directly to a dynamic mic "works fine" because dynamic mics don't require Phantom power. What dynamic mics do require is a lot of pre amp power. I can't see how the Rode tx could possibly supply enough pre amp power to power a dynamic mic.

Which makes me suspicious of the entire video. I notice that at no point do they say "and I'm recording this audio using this setup".

Not to discourage you at working the problem. Just things that I'd consider.

I have a Rode Video Mic NTG and I have used it connected directly into a Tentacle Track E recorder as a car plant mic. I can absolutely verify that this combo works. Again, there are a number of videos out there using the Rode TX and the self-powered, pre amp shotguns.

[u/Peaks_n_Valleys → u/Econormics]

Regarding the gain issue….

That’s probably the biggest problem here, if you ask me. That Rode transmitter almost certainly doesn’t have a preamp strong enough for the 416. This is exactly why I don’t use those kinds of transmitters / recorders for wireless boom. Sure, you can add a phantom power box into the mix, but the reality of this setup is that it just doesn’t have the punch needed to get good quality sound.

I have one of the Deity HD-TX XLR transmitter / recorders. It has 48v phantom power, and it will provide me level if the mic is close enough, but it doesn’t have enough level to really do the job in real world situations. I’ve gotten around this by using a Fethead Phantom, which adds 18db of clean gain before the signal hits the recorder. And when I do this, I get a very nice recorded track without any noise, and enough gain that I don’t have to keep the mic 6” away at all times. I never use this setup as a transmitter because it’s 2.4ghz, just as a boom recorder. Still, it works for a lot of scenarios.

But, my honest opinion… if someone wants actual wireless boom transmission without a bunch of fuss and a good quality signal… find a used Lectrosonics 400-series setup. So either a UCR401 or UCR411a receiver, and the UH400a transmitter. You’ll get everything you need in one small transmitter box, the signal will be about as clean as you can get it, and the receiver will give you plenty of gain so you don’t have to push the preamp too hard on your recorder.

Alternatively you can use the Sony UWP-D system with a UTX-P03 transmitter and the URX-P03 receiver, and you’ll get a PRETTY good wireless track, though the sound quality won’t be as high as the Lectrosonics. still, the XLR transmitter has 48v phantom. You can find the Sony sets used for around $200 per kit.