Audio impedence issues with BMPCC

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Francesco Bollorino

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Audio impedence issues with BMPCC

PostMon Jan 20, 2014 7:15 pm

After many trials using the BMPCC standalone and with ATOMOS SAMURAI as external recorder I have found some problems around the right matching of external microphone with the camera.
Here my observations waiting for your comments about:
a) there a clear incompatibility between the BMPCC and my external michophones (RODE and Sennheiser) due to wrong matching with the impendence of connection cable and audio input of the camera
b) Both microphones work great connected directly to Samurai
c) The Sennheiser radiomicroprohone doesnt work right with Samurai but work perfectly with BMPCC
My conclusion is that there a clear problem of compatibility and the problem lyas in the different inpedence as the signal with wrong connection is poor
let me know
Francesco Bollorino
Editor of Psychiatry on line Italia
Thematic Channel on Youtube
http://www.youtube.com/PsychiatryonlineITA1
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Thomas Thiele

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Re: Audio impedence issues with BMPCC

PostMon Jan 20, 2014 7:25 pm

Impedance missmatch would result in a muddy dull sound and some decrease in level.
Best example a shure SM57 (500 Ohm AFAIR) on a bad mic preamp.

You don't tell what mics exatly but I guess both are condensors. Those have low output impedance, so even a bad mic preamp shouldn't have impedance problems.

Make sure it's not one of the trivial ones: demaged cable, missing phantom power, wrong wiring.

P.S. I couldn't find a speck, where input impedance of he bmpcc is mentioned ... ;-(
BMPCC, Lumix G3, GF3
pana 7-14, SLRM 12/T1.6, sigma 19, pana 20/1.7, pana 14-42, pana 45-150,
pentacon auto 29/2.8, 50/1.8, 135/2.8.
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Francesco Bollorino

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Re: Audio impedence issues with BMPCC

PostMon Jan 20, 2014 7:48 pm

ThomasT wrote:Impedance missmatch would result in a muddy dull sound and some decrease in level.
Best example a shure SM57 (500 Ohm AFAIR) on a bad mic preamp.

You don't tell what mics exatly but I guess both are condensors. Those have low output impedance, so even a bad mic preamp shouldn't have impedance problems.

Make sure it's not one of the trivial ones: demaged cable, missing phantom power, wrong wiring.

P.S. I couldn't find a speck, where input impedance of he bmpcc is mentioned ... ;-(

the microphoes are perfect as they work at best using the input of Samurai the problem lies in the wrong match between the to inpendence of cable and camera input
I dont know what to do the microprophone worked fine on my SONY VG900 and its input was good also for the radiomic so the problem is in the BMPCC audio input set in a strange way I hope BM will solve the problem via firmware but I'm not so sure
Francesco Bollorino
Editor of Psychiatry on line Italia
Thematic Channel on Youtube
http://www.youtube.com/PsychiatryonlineITA1
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Thomas Thiele

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Re: Audio impedence issues with BMPCC

PostMon Jan 20, 2014 8:02 pm

Step by step.

What mic exactly didn't work with the bmpcc and how do you connect them?
BMPCC, Lumix G3, GF3
pana 7-14, SLRM 12/T1.6, sigma 19, pana 20/1.7, pana 14-42, pana 45-150,
pentacon auto 29/2.8, 50/1.8, 135/2.8.
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Chris Hocking

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Re: Audio impedence issues with BMPCC

PostThu Jan 23, 2014 4:03 am


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