Phantom II and AT4073a

[Scott Brickert]

I have an AT4073a feeding into an Artcessories Phantom II battery powered phantom power supply, feeding out through misc. adapter down to mini-jack for input into the camera. There's no signal or sound. Any thoughts? Could all the adapters (XLR male out, adapted to 1/4" male mono, adapted to mini-stereo) be crossed dropping the signal? (There's a new 9V installed).

thanks for any ideas,
Scott

[David Ennis]

Originally Posted by Scott Brickert

...Could all the adapters (XLR male out, adapted to 1/4" male mono, adapted to mini-stereo) be crossed dropping the signal?...

Absolutely. I'd say that your 1/4" to 1/8" mini adapter is designed for stereo to stereo, not mono to stereo. Both kinds look alike. If you have a multimeter or continuity checker you can test it. With the 1/4" mono plugged into it, if the middle ring of the miniplug is shorted to its rear sleeve, then what I'm saying is true. What you want instead is the tip shorted to the ring.

If you've got the situation I'm talking about, then when you plug into the camcorder, one of its stereo channel inputs becomes grounded and the other receives a signal. Some devices will give you the one channel, while some won't function at all with one channel grounded. Sounds like you have the latter. For instant gratification you could take a trip to Radio Shack and make sure you get a mono to stereo adapter, but this would be the better way to go for a reliable connection:
http://www.bhphotovideo.com/bnh/cont...ughType=search

But that will still give an unbalanced run (like you have now), okay for shorter cable runs only. If you are ever going to have an XLR cable run much in excess of 15 feet or so, this would be the best solution:
http://www.bhphotovideo.com/bnh/cont...ughType=search

[Ty Ford]

Unless there's a problem with the mic cable being bad, it's probably the cable between the Phantom supply and the camera. If you're feeding a mono (mic) signal into a mini stereo input, you need a cable with an XLR female on one end and a male 1/8" TRS on the other. That TRS has to be wired with pin 2 of the XLR to BOTH tip and ring on the 1/8" TRS.

It's a special cable. A regular cable will put the positive peaks on one track and the negative peaks on the other. You might actually hear audio in the camera headphones, but it's totally unusable.

Be aware that some camera audio IN jacks provide a small voltage sort of like Phantom Power, but NOT. With the Phantom Box in between the mic and camera, you may be OK. Some mics don't want to see that voltage and sound like crap if they are exposed to it.

There are a few cables on the market that have small blocking capacitors inside the XLR connector to stop that voltage from interferring with the mic.

Regards,

Ty Ford