Stereo splitter damages camera-gear?

[Shortwave8656]

I have a theoretical question regarding working with split sound into a stereo input of a mirrorless camera.

Most mirrorless cameras have a stereo input,
can I use a stereo-splitter cable (2x mono female to 1x stereo male) and connect for example a Rode NTG videomic into one input
and a DJI mic pro reciever into the other one - to for example a Lumix S5ii camera -
without having any interference that might damage the mics or the camera?

Relevant to know for people who wants to rent gear and use such a configuration, and warranty wouldn't cover damage.

Interesting to hear from someone who knows electronics in these devices. Maybe it's safe if most gear nowdays has surge protection?

 

[13engrsapper]

do both things require phantom power?

 

[Shortwave8656]

do both things require phantom power?

Let's say there are 3 scenarios, one where both mics need it, one where none needs it and one where only one needs it. Would damage occur in any scenario to the mic and / or camera?

 

[Khron]

Let's say there are 3 scenarios, one where both mics need it, one where none needs it and one where only one needs it. Would damage occur in any scenario to the mic and / or camera?

Where would said phantom power be provided from?

 

[Shortwave8656]

Where would said phantom power be provided from?

Built in 48v from the camera, no device in between.

 

[Khron]

Built in 48v from the camera

And this information is based on... what, exactly?

 

[Shortwave8656]

And this information is based on... what, exactly?

My bad, no mirrorless cameras on the market provides 48v phantom power through the 3,5mm mic-jack.

That eliminates one problem.

Let's say this only applies to active mics that normally would connect to the camera by a stereo 3,5mm.
Would 2x active mics fed through two separate mono channels into a camera stereo 3,5mm input cause any damage to any of the gear?

 

[ccaudle]

for example a Rode NTG videomic

This is one of those situations where "for example" doesn't really cut it, you have to pick specific devices and then check the specs.
The Rode NTG describes the output as "3.5mm auto-sensing USB-C," which seems like it is a weird hybrid beast of some kind.
"The auto-sensing output is an intelligent feature that seamlessly detects whether your microphone is plugged into a TRS input (like those on most cameras) or a TRRS input (what most smartphones and tablets have) and switches the output to accommodate. This means you don’t have to worry about using TRS to TRRS adaptor cables – the SC10 cable that accompanies the VideoMic NTG will work seamlessly with any device."

[Edit: and I am not sure how to interpret the "USB-C" portion of that, whether it is also USB-C, or whether it is only USB-C and there is some standard I am not familiar with for USB over 3.5mm TRS and TRRS connectors.]

Both TRS and TRRS sound like PC-style microphone connections which expect a bias voltage (probably 5V through 2K resistor, but that is going from memory of the old PC standard, so don't take that as accurate).
The first question I would have is what exactly is the expected TRS or TRRS connection? I do not know if there is a formal spec which defines how each pin is used.

You would have to compare the second microphone you want to use, and what it requires, and see if both microphones can live together with the same connection style in use.

Next would be the camera end. The camera abbreviated specs list this for the audio connection(s):
3.5mm for external microphone / external audio device
MIC (Plug-in Power) / MIC / LINE
Special Mic: Stereo / Shotgun *When attaching DMW-MS2 (sold
separately).
XLR microphone with DMW-XLR1 (sold separately)
4-channel mic input with DMW-XLR1 (sold separately)

That is a wide range of connection styles available. How do you switch between the different connections? The standard 3.5mm is implied to be mono, so do you have the DMW-MS2 for stereo microphone connection? Does the user guide for that device have detailed connection diagrams so you can evaluate what signals would be sent to each mono connector with a Y-cable?

 

[Shortwave8656]

This is one of those situations where "for example" doesn't really cut it, you have to pick specific devices and then check the specs.
The Rode NTG describes the output as "3.5mm auto-sensing USB-C," which seems like it is a weird hybrid beast of some kind.
"The auto-sensing output is an intelligent feature that seamlessly detects whether your microphone is plugged into a TRS input (like those on most cameras) or a TRRS input (what most smartphones and tablets have) and switches the output to accommodate. This means you don’t have to worry about using TRS to TRRS adaptor cables – the SC10 cable that accompanies the VideoMic NTG will work seamlessly with any device."

[Edit: and I am not sure how to interpret the "USB-C" portion of that, whether it is also USB-C, or whether it is only USB-C and there is some standard I am not familiar with for USB over 3.5mm TRS and TRRS connectors.]

Both TRS and TRRS sound like PC-style microphone connections which expect a bias voltage (probably 5V through 2K resistor, but that is going from memory of the old PC standard, so don't take that as accurate).
The first question I would have is what exactly is the expected TRS or TRRS connection? I do not know if there is a formal spec which defines how each pin is used.

You would have to compare the second microphone you want to use, and what it requires, and see if both microphones can live together with the same connection style in use.

Next would be the camera end. The camera abbreviated specs list this for the audio connection(s):
3.5mm for external microphone / external audio device
MIC (Plug-in Power) / MIC / LINE
Special Mic: Stereo / Shotgun *When attaching DMW-MS2 (sold
separately).
XLR microphone with DMW-XLR1 (sold separately)
4-channel mic input with DMW-XLR1 (sold separately)

That is a wide range of connection styles available. How do you switch between the different connections? The standard 3.5mm is implied to be mono, so do you have the DMW-MS2 for stereo microphone connection? Does the user guide for that device have detailed connection diagrams so you can evaluate what signals would be sent to each mono connector with a Y-cable?

Thanks for valuable insight. This is a open question where the specified mics are just examples. Point is to understand if damage can occur to gear when splitting the signal like this.
This is relevant for anyone renting or looking to rent camera equipment, or rely on such a setup with pro work.
There are people talking about this type of solution for using 2x mono mics in a stereo input of a camera using a stereo-split cable.
But what I am interested here with your guys knowledge and for future people looking for the same info before connecting their expensive gear like this, is knowing if it's safe or not.

So reduce my "for example" to any modern mic on the market. Is there a simple yes/no answer to if it will damage gear and can we have some general guidelines in how/why damage would occur?

 

[Shortwave8656]

Here is a guy who explains the setup and method in a popular video. I want to understand if it's safe and if it can be widely adopted cross different mics.

 

[pmfalcman]

Point is to understand if damage can occur to gear when splitting the signal like this.

Sole splitting, i.e. recording one source/signal to one channel and another source/signal to the second channel is not damaging per se.
I did this with Lumix G2 no probs.
It's just two signals being recorded to a stereo track. Whether they come from a single (stereo) source or two separate (mono) sources makes no difference.

The point is the camera accepts microphone signal level (i.e. certain voltage). Not line level, or even if such - not pro line level but consumer line level. They differ in voltages.

So - you do not need to worry about splitting signals (or rather - joining them) but levels the devices output.
If you input wrong level, in best scenario you'll end with distorted recording, in worst - burned up electronics.

Rode NTG, AFAIK, is meant for consumer cameras so no worries here. DJI - I don't know. Probably too - you need to make sure.

 

[Shortwave8656]

Sole splitting, i.e. recording one source/signal to one channel and another source/signal to the second channel is not damaging per se.
I did this with Lumix G2 no probs.
It's just two signals being recorded to a stereo track. Whether they come from a single (stereo) source or two separate (mono) sources makes no difference.

The point is the camera accepts microphone signal level (i.e. certain voltage). Not line level, or even if such - not pro line level but consumer line level. They differ in voltages.

So - you do not need to worry about splitting signals (or rather - joining them) but levels the devices output.
If you input wrong level, in best scenario you'll end with distorted recording, in worst - burned up electronics.

Rode NTG, AFAIK, is meant for consumer cameras so no worries here. DJI - I don't know. Probably too - you need to make sure.

.. So the worse that can happen is that the audio clips to the point where electronics starts to burn? Sounds pretty safe in this case ..

What about I line one active mic into one channel and a passive mic into the second? Same principle?

 

[pmfalcman]

.. So the worse that can happen is that the audio clips to the point where electronics starts to burn? Sounds pretty safe in this case ..

It is not about clipping.
Pro line level, peak to peak is slightly less than 3,5 V while consumer line level is ~0,8 V.

Just make sure you input mic level into your cam and you'll be fine.
As I said before - NTG is meant for cams like Lumix. DJI - you need to check what output type it provides. If everything else fails - read the manual.

What about I line one active mic into one channel and a passive mic into the second? Same principle?

Define "passive mic".


No matter what you plug in as long as it outputs MIC level.
It's the MIC input in your Lumix. You must match it.

 

[Shortwave8656]

It is not about clipping.
Pro line level, peak to peak is slightly less than 3,5 V while consumer line level is ~0,8 V.

Just make sure you input mic level into your cam and you'll be fine.
As I said before - NTG is meant for cams like Lumix. DJI - you need to check what output type it provides. If everything else fails - read the manual.

Define "passive mic".


No matter what you plug in as long as it outputs MIC level.
It's the MIC input in your Lumix. You must match it.

Thanks, I think this answers the question.

Aim to not feed anything that exceeds some 0,8 V output mic level. Can probably be checked in microphone manuals.
But that is not even specific to the cable-splitter question but to any microphone coupled normally to the camera stereo to stereo.

So short answer is - any mic duo can be plugged with a stereo splitter to a commercial mirrorless camera, as long as the mic level doesn’t seemingly stay on static red on the display db-meter because it could be exceeding ~0,8 V, which is what normal consumer line level is spec at.
This apply to any mic in any configuration - Active (with internal battery) or passive (no internal battery).

Tell me if I got it wrong but I think I get the picture.

 

[pmfalcman]

So short answer is - any mic duo can be plugged with a stereo splitter to a commercial mirrorless camera,

This apply to any mic in any configuration - Active (with internal battery) or passive (no internal battery).

Tell me if I got it wrong but I think I get the picture.

Well.... Not quite.
A mic with internal battery requires no external power.
On the other hand, what you call a passive mic, requires external power. Let's call it an externally powered mic. For short.
This external power is provided by your camera. Typically 3-3,5 V. You need to switch it on somewhere in the depths of menu. The deeper hidden, the better (such a lovely little game played by manufacturers).
Sooo... You activate this hidden power and you plug in a mic that requires these volts, in one channel. Perfectly fine. Mic works, camera works, everybody happy.
Then... you plug a mic that doesn't need these volts, it has its own volts inside, in the second channel. Not so perfect, I'd say..

Solution: make yourself a battery box for externally powered mic (pretty simple, receipes are to be found in the depths of internet). Then you have two mics that do not require any help from your cam.
You will spend an afternoon building a battery box instead of digging in the Lumix menu. A win, if you ask me.

 

[Shortwave8656]

Thanks for input! Hope this answers it for others who seek these answers.