Audio Levels - Fine When Recording / But Low Levels in QT-FCP

[Brian Broz]

Hi,

Im on a shoot in Mexico and the audio and levels seem fine on the camera (direct into camera w upgraded audio from a shotgun +48v). Peaking at -12db or so...but when the editor plays back the quicktime proxy in FCP the levels are peaking at -30db.

Has anyone experienced this?
Help!

Brian Broz

[Mike Burke]

Hi,

Im on a shoot in Mexico and the audio and levels seem fine on the camera (direct into camera w upgraded audio from a shotgun +48v). Peaking at -12db or so...but when the editor plays back the quicktime proxy in FCP the levels are peaking at -30db.

Has anyone experienced this?
Help!

Brian Broz

Yes.
In our situation, the audio channels in FCP were found to be out of phase.

Not sure where that occured as they were recorded at the Red in phase.
At any rate, disable one of your audio channels in FCP and see if that corrects your level.

[Brian Broz]

Thanks Mike!

Will check that out.
Cheers,

Brian

[Stephen Pruitt]

We have the exact same problem. The levels look great on the camera, but are very low in FCP.

However, the audio-out-of-phase explanation can't possibly be correct. FCP doesn't care whether levels are in-phase or out-of-phase. That would only make a difference during playback if one were playing two out-of-phase tracks simultaneously.

The levels are the levels. Each track is recorded independently of the other. When we look at the individual tracks, they are extremely low in FCP. . . almost flat line! And since, in our case, we only recorded one audio track, it can't be an out-of-phase situation internal to the camera that was somehow recording a combined signal to the one track.

My personal suspicion is that the RED's meter is grossly incorrect somehow. I would definitely like to see RED's thoughts on this important issue.

Stephen

[James Press]

We get low levels in FCP also, although it hasn't proved to be a problem. Record 4 shotgun mics directly to camera (with 48 Phantom power on). I set a mic level of about 40dB to make sure I get a reasonable signal in FCP/STP. At this setting the RED meters consistently push into the yellow bars. Sound quality is excellent.

[Aiden K.]

My personal suspicion is that the RED's meter is grossly incorrect somehow. I would definitely like to see RED's thoughts on this important issue.

I agree. The audio levels from RED are near flatline in FCP, but audio from, let's say the HVX200 match almost exactly neck and neck with camera/FCP.

[Steve Murray]

Getting the same thing. Very low in FCP.

[James Brundige]

Just received my upgrade and ran a line level test. -20 tone from Sound Devices, line input to Red at 0dB. (the other option is +10)

tone hit the hash mark, maybe a touch hot. Audio was fine as long as I did not exceed -20 out of the mixer. Not much headroom above that. Got pretty crunchy if there was any red on the Sound devices meter, which corresponds to yellow on the Red Camera meter.

The test tone reads out as -16 in FCP, which is -28 below unity. Sounds ok.

Still can't power my Neumann mics directly from the Red, so haven't tested the mic level input. Will try sending mic level from mixer.

conclusion:

It appears the Red runs at 0dB input level (as opposed to the usual pro level of +4dB or consumer -10dB) so be gentle when sending from a +4dB mixer.

[Stuart English]

Our line input reference level is 0dBu / 0.775 volts RMS / -20dBFS. Use 0dB Input Level for that.

In addition there is a +10dB Input Level setting for use with -10dBu (consumer) line level inputs.

[David Limpus]

Can I ask Stuart, which pro standard document did RED make it's decision on. Is it US installations? Or is there an other reason?
+4dBu = -20dBFS = 0dBVU SMPTE and +4dbu = -18dBFS = 0dBVU for Europe EBU R68