Canon M50 Stereo input via 3.5mm Jack

[nark]

Hi,

Just bought an M50 camera after reading that it has a stereo input and you cand feed in it a left and right independent tracks after reading the response of shadowsports at this topic:

https://community.usa.canon.com/t5/EOS/Is-the-mic-input-stereo-line-level-EOS-M50/td-p/306793

After testing the M50 I confirm that any signal sent on the M50 via independent tracks at a mic level scenario, the camera mixes the tracks into a "stereo" signal. 

So if you have a L + R microphone reciver pluged in via the 3.5mm jack, the tracks are not recorded independently (L + R), the camera mixes them into one mono video file.

So both of the VU meters on the display will ALWAYS move even if you feed the camera only on the left or right channel.

If anyone managed to split the left and right channels on the M50, please speak now.

PS: I tested the stereo input with a microphone in level and line in level. Both results are the same.

Thank you!

[kvbarkley]

Are the built-in microphones stereo? The specs say they are.

[nark]

Where in my comment did you see anything regarding the built-in micophones?

In your point of view built-in microphones = input?

Did you even bother to read the topic of this discussion?

[nark]

In your point of view built-in microphones = input?

Did you even bother to read the topic of this discussion?

[Lotus7]

The M50 -II Manual clearly states in two places thet the mic input is stereo.  In fact Canon actually sells a variable angle stereo microphone, the  for use with this camera.  I don't have a M50 to test, but from the published Canon literature, the audio input does appear to be fully stereo.

Are you sure you are using the proper stereo imput cables and/or adapters to access the mic input jack.  Canon DSLRs and Canon Mirrorless cameras use a single TRRS input with the left channle on the tip and thet right channel on the first ring. 

To input a stereo signal from two XLR mic(either dynamic or battery powered condensers) the left XLR pin-2 must connect to the 3.5 mm TRS tip, and the right XLR pin-2 must connect to TRS Ring-1.  This generally is best done with a dedicated Dual XLR to TRS "mic splitter cable".

NOTE:  Using a much, much more common TRS to dual TRS splitter and then a couple of XLR to TRS adapters will NOT work and will result in mono recording.  Standard dual TRS to TRS or dual TRRS tosingle TRRS splitters are inntended for headphone use and are wirred with all connectors in parallel.  They don't provide the Tip too LEFT and Ring to RIGHT separation required for stereo input.

[nark]

Hi Lotus7,

I have tested with the right cable from the lavalier reciver:




I have 2 TX and 1 RX from Saramonic.

I have tested the exact setup on a Canon 5D Mark II and I get independend audio on L+R (TX1 to L / TX2 to R)
I have tested the exact setup on my laptop and I get independend audio on L + R (just as the 5D)
I have tested the exact setup on my M50 and i get a mix-down of the both. If I speak on TX1, it gets recorded on L+R, the same when I speak in TX2.

I can only conclude that the M50 does not feed independent tracks from left and right OR I have to use a special 3.5mm jack?

[Lotus7]

Presuming you're using a WM2100 RX, and with the confirmation of stereo output you've done it should work. A "long-shot" but  Is there any possibility that because of the diameter of the body of the 3.5 mm plug or the right angle bend on the Saramonic patch cable that the plug is not fully seating in the M50?  If it's not quite seating all the way, the T and R contacts can be shorted together in the socket (jack) resulting in mono.    Seems unlikely considering your success with the 5D, but the M50 body is smaller.

Otherwise, either the M50 Manual is very misleading (mistakes have been known to happen in owner's manuals), or there is a strange "programming" issue due to some menu setting situation (again, seems unlikely since the settings are so simple and there is not a stereo/mono option) or you have a defective model with an audio input fault.

It makes no sense since the M50 clearly has stereo encoding capability using the built-in mics, so it has stereo mic pres and a stereo digital signal path.  Have you tried contacting Canon Support and asked for their opinion?  Good Luck.

[Lotus7]

Another thought:  Here's an easy test you can try without having to invest in additional cables:

1. Fully remove the patch cable plug from the M50.

2. Set up your lav link with the LEFT only mic operating.  That will produce a signal on the patch cable plug TIP only.

3. While speaking into the LEFT lav mic, slowly insert the parch cable plug into th M50 mic jack with the camera in Record Mode. while montering the audio level meters. Stop the instant the level meter(s) start to move.

As the plug is slowly inserted, the TIP should first contact the female jack RING contact (the RIGHT channel only) and you should see the R bargraph ONLY move.  If this happens the M50 will be indicating it can record stereo audio. That would indicake a mecanical "issue" between the Saramonic patch cable plug and the M50 jack.  If both channels' bar graphs move at exactly the same time, the M50 is, as you believe only recording mono.

Might be worth a try.

[arlinsandbulte]

@Lotus7  @nark  Did you ever get this resolved?

I might be experiencing the same issue with an M50 and Rode Wireless Go II microphone system.

To me, it sounds like there is a lot of cross-talk between the Left and Right audio inputs of the M50.

Using a TRS cable from the Rode mic system to the Canon M50.

Rode Transmitter 1 / Ch1(L): Transmitter is on and transmitting audio.

Rode Transmitter 2 / Ch2(R): Transmitter is OFF or Muted and not transmitting audio.

Even though the right channel should not have any audio (the transmitter is OFF or Muted), the M50 *DOES* record signal on that channel.  The right channel is about 10dB lower in volume and sounds muffled, like the high frequencies are rolled off (a text-book symptom of cross-talk).

Here are a couple of example audio files from the M50.  Left and Right have been split into two audio files.

https://www.dropbox.com/sh/xq29xfrixg5br21/AABlRgc8gCiXdKgg-IT0_Cuca?dl=0

I connected the same Rode microphone into a sound mixer instead of the M50, and the sound mixer does not have the same cross-talk issue.

So, from my tests, it seems the M50 has very poor cross-talk performance on its stereo microphone input.

This may not be noticable on 'typical' stereo microphones in which each side or channel is always on and both channels recieve almost the same audio signal. 

But, it can become appareent when using the stereo input independantly, where each side can get a truly independent audio signal.

[arlinsandbulte]

UPDATE:  Canon Tech support has confirmed that it cannot record the left and right signals from the 3,5mm TRS stereo mic input in 'true' stereo.  It will mix both tracks together.

Here is what tech support told me:

"Regarding the way the camera records audio, it is true that it will combine the audio together and it will not allow for separate channels to be recorded independently to their own left and right channel tracks per the external microphone that is used. [...] When recording video on the EOS M50, a stereo mic can be used, but per design of the camera, it will merge the audio together to where the left and right channel will have the same track."