For RED Engineers: optional 6V phantom power possible?

[Elizabeth Lowrey]

This came up in the thread about the tetramic, and I thought I would go ahead and ask in separate thread.

In most respects, the tetramic looks like a great and highly compatible tool to use in conjunction with RED: it's very compact and lightweight, offers tremendous sound quality and post-production flexibility (via software) in shaping the ambient quality of the recording, and uses 4 capsules for 4 discreet recording channels on a breakout cable that terminates in 4 mini XLRs for connectivity.

The only bummer is that it requires @ 4.5-6V phantom power rather than the standard 48, so you have to connect 4 inline phantom power transformers/adapters when used in connection with standard power sources, adding two sets of connections and considerable heft to each of the four lines that have to be secured and properly strain-relieved. You can see the phantom power adapters (minus XLR cables running completing the connection to the camera ports) in the picture below:

Though I can guess the answer, I still have to ask if it's reasonably possible to get the RED camera to offer an alternate 6V phantom power voltage to its standard 48? Is it something at all that could be controlled via firmware and selected in a menu somewhere?

 

[Adrian T.]

I suppose it would be easier to ask Core Sound to support the standard 48V phantom power instead of asking RED to support a non-standard voltage. :wink:

 

[Elizabeth Lowrey]

I suppose it would be easier to ask Core Sound to support the standard 48V phantom power instead of asking RED to support a non-standard voltage. :wink:

Believe me, the thought occurred to me that I should do this in reverse, but as I've been having a dialog in the other thread with Len from Core sound, I got the distinct impression that there were crucial design features that made the non-standard voltage necessary for what they were trying to accomplish.

I'm certainly not asking here for a redesign or substitution of hardware in the RED, just a gentle inquiry if, by some chance, this is the kind of thing that can be handled by a simple firmware change. If not, no problem. But you'll never know if you don't ask.:wink:

 

[Len M.]

I suppose it would be easier to ask Core Sound to support the standard 48V phantom power instead of asking RED to support a non-standard voltage. :wink:

We do support the 48V phantom power standard using a compact Phantom Power Adapter (PPA). Eclaire is looking to eliminate the PPA.

 

[Kevin Halverson]

With a source impedance of 6.8k per leg, obtaining lower supplies from any 48 Volt phantom supply is a trivial matter.

Typical microphones require 4 - 5 mA of current (used for their impedance converters and/or preamplifiers). When these microphones are connected to a standard 48V phantom power source, the result is a supply voltage that is between 20.8 to 14 Volts. Higher current consumption results in lower voltages. If a microphone required only 6 Volts, then all that is required is a resistor or better yet, a zener diode.

There is no reason for RED, nor any manufacture to depart from this standard as the microphone can, and should, provide its own regulation scheme.

Kevin Halverson