OT- Pluggin 2 mics Into Mic input

tadpole wrote on 9/16/2004, 3:00 PM
Hi all...

Here's the plan. I have a shotgun mic (mono i believe) and wireless mic (stereo). I want to record to discrete channels, on the cheap.

So, i got a Mini Stereo Y Adapter, and plug the shotgun input on one side, and wireles mic input into the other - then plugged Y adapter into my Stereo Mic input on camcorder.... Thinking the resulting recording would be shotgun sound on left channel, and wireless sound on right channel....

Can't get this to work though!

Plugin only the wireless mic into the Y adapter, I get stereo sound
Plugin only the shotgun (mono) into Y adapter, i get mono (left channel) sound

Plugin both in at the same time - i get nothing!

Before i go out and buy some more adapters to try out.. hoping someone
could explain how these adapters work?



Chienworks wrote on 9/16/2004, 4:58 PM
The Y adapter you have splits both left and right channels to both jacks. The shotgun mic has a mono plug (notice only one divider between the tip and the sleeve) and it shorts the right channel to ground. You'll get only the left channel from the shotgun no matter which side of the Y you plug it in to. The wireless mic is almost certainly not stereo, however, it has a stereo plug on the end (notice two divisions giving you tip, ring, and sleeve) so that it is compatible with stereo mic inputs. This is achieved by having the tip (left) and ring (right) shorted together in the plug. Now, for the kicker, when you plug both in, you short the right to ground and the left to the right, which means that both left and right get shorted to ground, hence no signal at all.

What you need is a Y adapter that splits the two channels into separate mono jacks. This may be a custom order as i doubt this is a common item. I believe the adapter you are using was intended to allow you to plug two sets of headphones into a single jack and therefore has two stereo jacks. This is by far the most common form of stereo Y adapter.
HPV wrote on 9/16/2004, 5:10 PM
Radio Shack sells a Y cable that will give you discreet L/R mono jacks to a stereo plug. If it doesn't like the stereo plug from your wireless mic you'll need to get a stereo to mono adaptor plug. If you go this route, make sure to tag it with some spray paint so stand out from your other like adaptors.
Something you'll need to watch out for is a drop in the impedence value you present to your cameras mic input. You might end up with a very low or noisy signal. Or both. If that's the case, you'll need to get a mixer with a mic level output to go between your mics and camera.
Craig H.
wcoxe1 wrote on 9/16/2004, 7:52 PM
Radio Shack, bless their hearts, has little jacks for just about every combination you can dream of.

I have been using exactly the setup you discussed for over 2 years. The problem is that it took a Y splitter cable and two jacks on the end to do it.

I COULD have done it with three jacks, but the long sting of jacks sticks out so far it becomes delicate. Don't recommend it. The Y cable allows you to tuck the mess safely out of the way.

Just make sure the direction of the various splits is exactly what you want, not the opposite. They had to order some of the things for me after we discovered that everything in the store was exactly opposite of what I wanted. No additional cost, just not in stock.

Have fun.
tadpole wrote on 9/19/2004, 2:15 AM
Answers here were SO much more helpful than the "duh" i got from radio shack folks! thank you thank you!

(sorry for bumping a thread with no further 'helpful' input - but just had to thank u guys for you responses.. VERY helpful .. thanks again!
Ps - wcoze1 - if you could please email me jmale2000@yahoo.com (or post) your exact setup, i would appreciate it.. i picked up some different adapters, but experiencing a level drop as HPV mentioned... thinking my setup is still a bit hosed :)

musicvid10 wrote on 9/19/2004, 7:53 AM
I don't suggest using a Y-adaptor to combine mic signals under any circumstances. Doing so sends the signal from one mic right to the element of the other. There are different types of mics and impedances so connecting them in this way can short or disable one or both mics especially if one is amplified as your wireless mic is.

A mixer isolates the incoming signals and combines them in the output. I don't suggest doing it any other way.
Spot|DSE wrote on 9/19/2004, 8:38 AM
Using a dual mono to stereo plug such as described above is no issue whatsoever. Stereo to stereo, mono to mono are both problematic, but using an adapter such as
is no problem at all. The only matched line is the ground and this doesn't affect the signal of either run.
A mixer is not needed if only two mics are to be put into the camera and they are both mono, or if only one side of a stereo mic is being matched to a mono mic. In Tadpole's wont to do stereo AND a mono mic, this simply can't be done without using 4 channels, 12 bit/32k crappy audio. Better option is to take one half the stereo mic feed and the mono mic, or both feeds from the stereo mic.
musicvid10 wrote on 9/19/2004, 11:05 AM
Sorry Spot, I didn't read his first post closely enough. I thought he was going to combine the signals to one output.

If he wants to send one mic to L and one to R to a stereo input, I agree there is no problem except for the stereo-->mono issue for the one mic. I've tried combining L/R from a stereo mic directly to mono with less-than wonderful results. I'd still use an external mixer in that instance.

Tadpole, what kind of wireless mic do you have that has a stereo output? Or possibly is it balanced, in which case a direct box would give you the signal you need to go to an unbalanced input on your camcorder.
farss wrote on 9/19/2004, 3:20 PM
If it is a balanced wireless mic and many of them are, with the + on tip and - on ring then you can get a really interesting thing to happen. Your left abd right channels will contain the exact same audio 180 deg out of phase.
It sounds just fine until it's broadcast and anyone with a mono TV hears nothing that came from the mic. Normally the stations Out of Phase' alarms would go off except if you've mixed some background music in there's enough correclty phased audio to keep them happy. In this case the mono listener just doesn't hear the dialogue. So be very careful and as a final check always monitor again in mono.