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12v to 48v phantom??


Michael P Clark

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Well I'm not having any luck finding one, so I am assuming it doesn't exist in a barrell format.

On another note, Is it safe to send mic level from a mixer or a wireless reciever into an input that has 12v power coming out of it?? We are attempting a modification that will disable an onboard mic that is recieving 12v from the camera to accept a better quality (416T) mic, but will like the option to send it a wireless reciever or mixer output depending on the situation, at a later time. I know that 48v is safe, but what about 12v? Thanks in advance!

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Hi Michael,

I had a bad experience with a 12V T powered input on a SD442.  I had it inadvertantly switched on and when I plugged a Lectro 411 receiver into it I got a slight buzz on that channel. I tried everything to chase down the problem, swapping out cables etc. I was powering the receiver and the mixer from a BDS box. When I ran the 411 from internal batteries, the buzz disappeared.

Assuming the BDS power cable was the problem I switched it out too. No go. Finally I noticed the T power switch was on in the mixer (my eyes aren't what they used to be) and the problem disappeared for good. Didn't seem to cause any damage to the 411. I then remembered a similar problem I had years ago with an FP33 and a Sony wireless. No buzz, but a loss of low frequency signal. I guess my memory's not what it used to be either. Anyway, watch out for that T power.

Chris Newton

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Thanks Chris!

Now, here's another question, does 12v ALWAYS mean "12v T"?

I have also noticed that there is on consignment at one of our many dealers a "Micron In-Line DC/DC Power Booster". Has anyone had any experience with this? It says it accepts 5-10v and converts it to 48v. I know that most voltages have +/- "n" voltages so a camera stating a 12v output could actually be 10-14v, less or more. I don't see this product on Micron's website either, for any other info. I also found an in-line adapter from Audio Ltd., but it was for rental somewhere in the UK, and not on their website. I am thinking it was for their wireless transmitters. Anyone ever seen one of these?

I know my line of questioning seems odd, but I was hoping to put the same mic on my pole(CS-3e) on the cameras, but this 12v output is really hampering that point. And I don't see alot of 12v mics out there anymore(at least enough to fulfill this job). I will be strapping onto the cameras a Stereo Wireless receiver and I might just strap a Denecke PS-1 as well with the CS-3e's. As long as it's not too bulky.

Would I experience any issues with the 12v after I supply a 48v from the PS-1?

Perhaps, the 416(12v) would be the answer, and fo'get about it!

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Thanks for the offer Curley, but I'm based in Atlanta.

I did some tests on my own in regards to running a mixer or wireless into a 12v source input and here is what I came up with...

I ran a schoeps into my 302, and came out mic level into my 442 that was switched to 12v T, and it sounded clean. I cranked it up to try and hear if there was any low level buzz and nothing. So I tried Chris's problem, and ran my 411 into my 442 with 12v T switched on and it also sounded clean. I am powered BDSv2 as well. So, I didn't get the same issue as Chris, and it seems like running mic level into an input that is outputting 12v T is running clean.

Am I doing something wrong? missing a critical step? I remember my mentor warning me a lot about staying away from 12v T power, but I am experiencing no problems or noise. Is 12v T only an issue with dynamic mics?

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Guest Jeff Colon

Hi Michael,

Good observation.  12t and 12 phantom are very different.  Some older field mixers like the shure fp 31 put out whatever was in the batteries for phantom power. While phantom powered microphones will work on lower than true 48 volt phantom, true condensers will sound noticebly bad at some lower voltages...electrets sound noticebly mediocre at all voltages ;-0.  Not too long ago it was pretty standard practice to have an outboard microphone power supply. PSC Sennheiser Deneke all were popular and some provided both 12t and 48v phantom as well as high pass filters and pads... for eng I have not used an external power supply in the last ten years as the psc and sd mixers both generate 12 and 48...  I use Shoeps, Sanken and Sennheiser on 48vph... my favorite microphone is the first one I bought... 20 year old 416t.  in the heat of battle, I have screwed up and sent 12t (a couple seconds ) to everything except a ribbon mic with no damage...yet.

one caveat, the SD442 allows for choice in phantom voltages... an MKH 70 will sound awful on 12v phantom... SD could lose this feature for me as I'm not powering mics with the internal batts and don't need runtime consideration.

To answer your original post, There is no barrel step up transformer accomodating 12t to 48v phantom that I have seen... You can buy individual mic power supplies in both 12t and 48ph on ebay for days.  As long as you don't send 12t power to something not for it's use, you will not have a problem... the only reason to avoid it would be if you're an idiot like me and occasionally forget... or accidentally hit the wrong switch;-(... Phantom is just what it's name implies... there have been numerous threads on the user groups regarding sending 48ph to console inputs and wireless recievers... i've never had an issue there, but do try to keep it turned off when not needed....  12t mics sell for hundreds less than 48ph for what that's worth.

Google up Phantom Power and 12 volt T power "Tonador" and don't hesitate to put a voltmeter on a power supply...... it's all Gris Gris and Monkey Dust...  Mardi Gras kicks off this weekend.

Jeff C

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  • 6 years later...

Doesn't PSC make a $39 barrel adapter that will allow a 12V T power such as the 416 T to work off of a SD664, which allows for 12v-48v powering but no T powering....?

 

 

YEs! PSC make that barrel that works from 48V Ph to 12T (that will generate 48V Tonader) but never tried to 12V

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Rolls makes some 12V to 48V adapters, mind you these are NOT 12v T power to 48V phantom, but actually 12VDC power supply, such as from the same power source you are powering the rest of your bag from.  There is a single channel and dual channel version.  Most other phantom power boxes, including the ones made by Denecke and PSC, utilize 9V supplies from 9V batteries, and couldn't be run from bag power... just a suggestion for a possible solution to the issue, taking it from an alternate approach.

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