DIY Audio Cable for Arri Alexa

[Cujo]

Referenced in another thread in the Camera section, I am posting a pic of a DIY cable for the Arri Alexa.

This is an inexpensive solution to buying a factory cable to add a wireless scratch track audio signal.

You will need a 5 pin male straight connector, a 3.5mm male connector with cable, epoxy, soldering tools, a cutoff tool (Dremel, or hacksaw), and a few minutes time.

I had helped make a set of these on another feature with Bud Raymond and on this particular movie, my bad-ass sound mixer, Todd Weaver and I whipped these up in record time on set one day when it was discovered that the camera rental company had failed to include them as a part of the agreed rental kit.

Production made a few frantic calls and was all set to accept that there would be no scratch track for the first day of shooting.

Sound team to the rescue... camera rental house to the back of the line. No soup for you !

A 90* 5-pin connector was not immediately available and we needed an instant solution... This worked and worked well.

Take a straight 5 pin, remove the guts, and cut the housing to approx 1.25 inches. This length is not super critical, but try to get close.

Install the guts and make your solder connections.

Fill the top with epoxy (we used fast cure) and give it the required time to cure.

Plug and Play

It's not as pretty as a nice shiny 90* connector like I've built before, but its also way cheaper, works perfectly, and was an instant solution available on set when we needed to make it happen.

[johnpaul215]

Great idea! What is the minijack side made for plugging into? Does it just feed CH1?

I will be making one of these for the scratch audio days.

[Cujo]

On this particular cable we can send a scratch to L or R channel in the Alexa using a Comtek pack.

The Alexa has a nice menu that allows you to choose which channel you want to send audio to. Send tone and adjust the camera gains, change the battery every day in the Comtek and let it ride....

Works like a champ.

[johnpaul215]

Cool, thanks!

[Todd Weaver]

_{I think I still have epoxy stuck under my fingernails.}

[SoluSon]

Nice!!

[nhaudio]

Do you have the pinout for the Alexa 5 pin XLR? 

 

I would guess :

Pin 1 = screen

Pin 2 =  L +ve 

Pin 3 = L -ve 

Pin 4 = R +ve 

Pin 5 = R -ve

 

can somebody confirm?

[Jack Norflus]

can somebody confirm?

Yep confirmed.

[nhaudio]

thanks

[studiomprd]

" can somebody confirm? "

that's what it says in the manual,  and it is pretty much the industry standard...