# Phantom power via line-in?



## Coffee (Nov 5, 2010)

Hallo to everyone here, this is my first post in this interesting forum.
I've been searching for a good measurement solution for Macs and finally came here. I had a very old Clio measurement system running on an 486 with DOS (Yes, that old!) and it finally gave up definitely.
For a while I used the Audionet Carma on my Imac, but after a java update it kept crashing and crashing. As it wasn't too good anyway I decided to look further and I downloaded REW.
I can't get it to work properly as the soundcard cannot be calibrated. My Mic, the one supplied with the Clio needs Phantom power. 
In the REW instructions it says: 
"A soundcard (internal or external) which supports full duplex operation (simultaneous replay and recording) with line inputs and outputs. Note that microphone inputs are NOT suitable and should not be used (they have too much gain and most suffer from high noise levels and limited bandwidth)."

If I connect the Mic to the Line input it has no Phantom power and doesn't work at all...

What can I do?

Nick


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## Kenneth R. (Oct 20, 2010)

you can get an in-line phantom power box. These run about $40-50. Not sure how this would affect the calibration, if any, but it will provide for your mic.


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## Coffee (Nov 5, 2010)

Interesting... I'm just wondering if there exists a separate phantom power box maybe there's a soundcard with phantom power in the line-in, too? 
My soundcard is not the best so I'm thinking of replacing it anyway...

Am I the only one with a measurement mic that needs phantom power?

Nick


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## JohnM (Apr 11, 2006)

Many people are using ECM800 mics or similar with interfaces that provide phantom power. There are several USB soundcards that offer that, see this post for a discussion of some of them. The cheapest route is probably a simple mixer like Behringer's Xenyx 502, which has phantom power nowadays (older ones didn't).


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## Kenneth R. (Oct 20, 2010)

Coffee said:


> Interesting... I'm just wondering if there exists a separate phantom power box maybe there's a soundcard with phantom power in the line-in, too?
> My soundcard is not the best so I'm thinking of replacing it anyway...
> 
> Am I the only one with a measurement mic that needs phantom power?
> ...


Certainly not, I too required phantom power for my Earthworks mic.


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## Coffee (Nov 5, 2010)

I've been searching for soundcards with phantom power and, as an alternative, for mics that don't need phantom power. The ECM 8000 seems to be highly accepted here so that was my first choice but I found out that this mic also needs phantom power...:gulp::gulp:

John, you replied that the ECM "provides" phantom power. Was that a typo as in my understanding mics that don't need phantom power simply have a battery to get the necessary power. But the Behringer doesn't seem to have batteries...:unbelievable::rubeyes:

Or ist it just a sensitivity problem?
Here's a link to the mic I'm currently using with technical data:
http://www.audiomatica.com/mic.htm
What soundcard would make sense to use with this mic and REW?

Nick


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## Wayne A. Pflughaupt (Apr 13, 2006)

John said that people use the ECM800 with *interfaces *that provide phantom power. The interface would be a sound card that has both phantom power and a mic pre amp.



> What soundcard would make sense to use with this mic and REW?


Judging from what I see at Audiomatica’s web site, this mic has an RCA output? If so it will require the company’s own pre amp, and in that case any sound card with RCA inputs and outputs will work, as long as its compatible with your computer’s operating system.

Regards,
Wayne


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## Coffee (Nov 5, 2010)

Yes, the mic has an RCA output. But normally there's no need to get the mic preamp as it's expensive and suggested as an option only.
You get an idea about some clio prices here:

http://www.e-speakers.com/-strse-Shop-By-Brands-cln-CLIO/Categories.bok

Any phantom power will do it. But for REW it has to be fed through the line in and that's the unusual part about it.
With which soundcards can you connect the Behringer mic, I think these should work with the Clio mic, too.

To make things a bit more complex, my favorite solution would be a soundcard with an AES/EBU digital out and Volume control so I can directly feed my new DCX 2496. But that will probably stay a dream...

Nick


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## Wayne A. Pflughaupt (Apr 13, 2006)

> Any phantom power will do it.


I have my doubts, Nick. Phantom power is typically fed to a mic only from a mixer or pre-amp’s balanced XLR inputs. IOW, there is no phantom voltage on the line level inputs of a mixer, audio interface, etc. 

Regards,
Wayne


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## JohnM (Apr 11, 2006)

Those Audiomatica mics are low voltage electrets, although they specify 8V they would probably work with the 5V of a PC soundcard's mic input. The reason REW advises against using PC soundcard mic inputs is they often have filtering at low and high frequencies, which is fine for voice but not much use for measurement.

The ECM8000 can be used with the Xenyx 502 I mentioned earlier (a low cost solution). That provides the 48V phantom power required and has a mic preamp to convert the mic's input to line level. I would *NOT* recommend you connect a Clio mic to a normal 48V phantom power interface, it specifies 8V.


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## Coffee (Nov 5, 2010)

After checking with Audiomatica (48V does work) I bought the Tascam US-144 soundcard with 48V phantom power (people here seemed to like it and it has AES/EBU digital out so I'm hoping to get a digital connection to my Behringer DCX 2496 from my Mac.

What can I say... it sill doesn't work! I can't get any signal to REW. I even can't calibrate the soundcard!
The input level on OS can be adjusted fine however and I have the 1khz output from REW, it's only the input section that doesn't work. I tried with all possible levels and with 44.1 and 48 khz...

Help....please... I'm frustrated!

Nick


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## JohnM (Apr 11, 2006)

Bad news I'm afraid, in a Java update around June time Apple did something which broke input from 4-ch soundcards, see this thread for details. The OP found a way to reinstall an earlier Java version and get things working again, but it did not seem like an easy process. Other options for the Mac are running the Windows version of REW under bootcamp or trying FuzzMeasure, a Mac application (but not free).


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## Coffee (Nov 5, 2010)

Oh my god... that's bad news!

But this would explain another issue I had with another measurement program.
It is a nice little java based program from the german high end manufacturer Audionet and it is called Carma:

http://www.audionet.de/main/service/downloads/carma-v30/page.html?L=en

I didn't use it for two month as I was building some new speakers and when I was ready to measure them Carma always kept crashing during measurement saying it was bcause of a java problem...

After spending many hours to fix it i was looking for a new program and I finally came to REW...


Nick


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## tkollen (Feb 4, 2012)

I have a Clio mic that I want to use for my EMU 0204 external sound card. The card itself provides 5 volt phantom power which is too low for most condenser microphones where 48 volt is typical. It is even too low for the Clio mic that requires 8.4 volt and can accept up to 24 volt. 

The Clio mic has a female phono connector only and is therefore unbalanced. I have been thinking about connecting a 9 volt battery in series with a 2.2k ohm resistor between the signal and the ground wire (contained in a small box) . 

Would this be an acceptable method to solve this problem? I would appreciate any comments on this topic.


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