Two Audio Sources

[Michael Middleton]

Is it possible to have two audio sources recorded on the PDX-10? I have a wireless mic (mini), and when I plug it in, it overrides the standard shotgun mic. I'd like to be able to record with both, if possible? Would it be possible if I had XLR wireless instead of mini?

Thanks,

Michael

[Ignacio Rodriguez]

Yes. And you can set the input levels (line, mic, mic with att) and manual gain for each channel seperately when using XLR. You can add an adapter to connect that current mic to one of the XLR inputs, although the best option is probably to get a mic with XLR connection, it will probably be a better mic anyway. You could try making an adapter yourself connecting pins X and R to the mic's negative and L to the mic's positive... this will lose you some gain for that channel but the wireless receiver probably outputs a hot enough signal so that should be ok. Just make sure you keep that channel's Phantom power setting off at all times, otherwise you might damage the camera's audio input or the receiver's output.

[Michael Middleton]

Cool, thanks. I'll be testing an XLR mic this weekend. I settled for a cheaper VHF mic with mini because I wasn't worried about interference in the application I primarily use, but I failed to consider that I couldn't record on two channels with the mini. Once again, a case of trying to save money ultimately costing more in the long run!

Michael

[Ronald Lee]

Michael, I am in the EXACT same situation as you. I looked today and the stores I went to said there is no such thing as a female mini plug to male XLR, but they think they can make it for about $50 (Canadian).

I think I"m going to get it made.

I bought a Sony WCS-999 wireless...great mic, by the way.

[Sean McHenry]

Built one yourselves.

All the parts are available at the local RatShack.

At least they used to be. Female 1/8" about 2 feet of GOOD QUALITY shielded audio cable and an XLR. I always make my own cables. I use Neutrik XLRs as they are hands down the best.

You can get them from Markertek too. All in all, parts should run about $10 or so. Even if you buy a cheapie soldering kit for $10 you'll be ahead.

Look for "XLR diagram" or "XLR Pinout" on Google.

Sean

[David Hurdon]

<<<-- Originally posted by Ronald Ng :the stores I went to said there is no such thing as a female mini plug to male XLR, but they think they can make it for about $50 (Canadian). -->>>

Ronald, I bought two female mini-pin to male XLR adapters from B&H when I got my Beachtek unit for a Sony VX2000. They don't magically turn an unbalanced mic into a balanced one but they certainly exist and function. I believe they were around USD$10-15.

David Hurdon

[Ronald Lee]

Yes, these are the one!! I can get it shortened I think after a buy then (I don't need 3-10 feet of cable hanging off my camera, haha).

When you say that don't replace balanced audio, what kind of symptoms are you hearing? lots of hiss, statics??/

[David Hurdon]

The most obvious problem I've had was picking up broadcast radio on a 30' mic extension on a lav. I've since been told that replacing the run with an XLR cable would probably improve things but not eliminate the problem.

David Hurdon

[Sean McHenry]

A few quick note on the subject, especially radio interferance or RFI.

All cables are effectivly antennas for a given frequency. Several things you can try doing to help, most are marginal especially if you are using marginal wiring for these cables. Not all 3 conductor wire is good for a mic cable.

First, try varying the length of the cables. When you do this you change the naturally resonant frequency for the cable. All cables are a mixture of capacitance and resistance. This forms an interesting circuit.

Second, try to minimize the connection points on any given cable run. That is, use (2) 25' cables instead of (5) 10' cables. Each connection point has potential to somewhat rectify a signal source nearby adding it's frequencies to those you actually want traveling on the cable. Sort of the old fillings in the teeth picking up radio stations thing.

Third, try coiling a small loop of several turns of mic wire at the beginning and end of the cable runs. In Amateur Radio, as anywhere else, this can help isolate the line a bit by creating a "choke" for various frequencies. This choke effect depends on the size of the coils and number of turns.

Last, you could try getting some of those clip on ferite cores available at Radio Shack or similar store. They also create a choke effect for stray RFI. These are a good idea if you make or extend your power cables by the way.

And yes, balanced to unbalanced connections, like on most consumer camcorders are an issue that really require some circuitry to overcome, not just a special cable. Although, having a cable made up that does change the connectors alone is at least something when that deadline is near and the BeachTek, or even a cheap mixer is not around.

As an alternate, you may look into a cheap mixer that will accept balanced/unbalanced inputs and has an unbalanced output. Check the Behringer mixers. Or try the Samson Mixpad series.

Sean McHenry