Alien Bee and White L Stereo Plug

[FlashZebra]

The Alien Bee (AB) and White Lightning (WL) monolight flash units (both from the same company) both seem to use a stereo plug on the sync connector.

The White Lightning units typically accept a 1/4 inch stereo phono plug, and the Alien Bee units accept (and come packed with) a 1/8 inch stereo phono plug.

I have gotten both Alien Bee and White Lightning units to function just fine with mono versions of these plugs (sync cords, radio slaves, etc), and a sync connection intrinsically just needs two contacts like a mono plug (the stereo plug has three contacts).

I have long speculated what the purpose of the extra contact on the stereo plug for the AB and WL might be for.

My best guess is that it might turn off the optical slaves present on all these units when something is plugged into the jack on the flash head. But, this is just a guess.

Anyone know exactly what function this extra contact on the stereo plug might accomplish on AB and WL monoheads?

Enjoy! Lon

[bwolford]

I don't think stereo is to disable the slave. Mono plugged into the sync port will disable the slave.

Brice

[Curtis N]

Stereo plugs are produced in higher quantity, easier to find and cheaper, despite their slightly more complex design (just a hunch).

[SkipD]

No studio flash unit that I have ever seen ever uses more than a two-conductor trigger circuit. All of my AlienBees sync cords came with "mono" plugs, though I use ordinary stereo headphone extension cords to make a much longer cable at times for connecting to my light meter (which can trigger the lights). In other words, either two- or three-conductor plugs will work just fine.

[FlashZebra]

No studio flash unit that I have ever seen ever uses more than a two-conductor trigger circuit. All of my AlienBees sync cords came with "mono" plugs, though I use ordinary stereo headphone extension cords to make a much longer cable at times for connecting to my light meter (which can trigger the lights). In other words, either two- or three-conductor plugs will work just fine.
I saw at least three Alien Bee cords that came with Alien Bee flash heads that had stereo mini plugs. But, I repaired one and used a replacement mono connector and it works fine. There were only two wires and of course the PC connector on the other end only has two poles. Radio slaves with a mono connector also work just fine.

As Skip indicates, of course a standard sync connector only needs two connections, as with a mono connector. But it seems the stereo connector may be in widespread, but not exclusive use with Alien Bee and White Lightning (see links below).

Possibly it is just as Curtis speculates, the Alien Bee cords are just constructed using whatever inexpensive and available plug stock might be handy, sometime it might be a stereo connector, other times a mono connector. But why go to the trouble to stipulate "stereo" and photograph "stereo" versions in the cord and adapter descriptions shown in the links below?

But either seems to work.

So, possibly I may be looking for a function that is just not there, especially since others have seen Alien Bee supplied cords that have mono, not stereo, connectors. But, when I saw the stereo connector on those Alien Bee cords, I thought, why a stereo connector? But, stereo connectors are either shown or cited in most of the cords and adapter available at either the Alien Bee or White Lightning website (links below).

So the cords I saw are likely not just mistakes.

Please note the prominent stereo connectors in the cords and adapters available for both White Lightning and Alien Bee units:

http://www.white-lightning.com/cords.html

If you click on the individual cords and adapters in this link you will see that “stereo” is stipulated or pictured on most of them.

http://www.alienbees.com/hardware.html

Enjoy! Lon

[FlashZebra]

More White Lightning stereo sync plug connectors at Paramount:

http://paramountcords.com/products.asp?cat=59

The stereo sync cord mystery thickens.

Enjoy! Lon

[Curtis N]

If there is no wire connected to the third contact of a stereo plug on an adapter cord (and you could figure this out easily enough with a continuity tester or ohm meter), then a stereo plug will behave the same way as a mono plug.

Looking at the exorbitant prices on some of those cords, I can understand why you would want to build your own.

[bwolford]

If you go to the http://strobist.blogspot.com and read Lighting 101 there's an entry about how to create your own sync cord using 16 gauge power cord. Now, I'm no electrician, but I know there's only 2 wires in 16 gauge power cord. And this sync cord will work with Alien Bees and White Lightning. IE, only 2 wires are necessary.

Brice

(EDIT: CORRECTED THE LINK]