Lack of VU finally burned me...

So, I've never been all that bothered by the fact that the BMCC doesn't have audio meters. I want them, but they were never promised and there are workarounds. Personally, I use a "pre-flight" check when setting up for interviews. These steps ensure I don't miss anything in the setup. I know all the "safe" settings for my mic/amp/BMCC audio setup.

Well, last night I was rushed. Skipped some steps. Maybe I'm just getting too comfortable with the camera. Maybe I should stop them from rushing me. Anyway, I skipped a couple steps and I left my input set to mic, when it needed to be line.

ALL of my audio is blown out.

Totally MY fault...but since I haven't bought my alphatron yet, it really made me curse the lack of meters on the BMCC. Even if we could just get just a peaking warning, it would be extremely helpful.

So, does anyone know if there is *anything* I can do with blown audio? Pretty sure I know the answer, but I thought I'd ask just in case...

(feeling stupid)

So, does anyone know if there is *anything* I can do with blown audio? Pretty sure I know the answer, but I thought I'd ask just in case...

Sadly it's more or less the same answer as if you'd overexposed the video by about 6 stops, which is the sort of thing it equates to...

That's pretty much what I thought...

Hi Sean, you used headphones?

Hi Sean, you used headphones?

Sometimes, but this was a noisy environment and I find the headphone output pretty weak on the BMCC, so in that environment it's impossible to gauge your levels. I definitely would have know I was clipping, but since I usually don't have that problem, I wasn't trying to use headphones in a situation I wouldn't normally used them.

I liken it to driving a submarine. There's no window, you can't see where you're going, you have to navigate based solely on your instruments. I've tested my mic/mixer setup extensively to dial in solid settings that work in 95% of my situations. I can work off of the meters on the audio mixer and keep my BMCC at 80% and get good audio. If I had followed my procedures, this wouldn't have happened. Still, if the BMCC had any sort of audio feedback, it also wouldn't have happened.

After shooting on DSLRs for years and knowing the audio limitations of recording audio on those, l've just made it a habit of always backing up the audio with a small external recorder like a H4N in addition to on the BMCC too. It is such an easy to do back up. I guess I don't know exactly what you are shooting but that recorder and a split can fit in your pocket or a tiny shoulder bag so it should be a simple thing in most cases.

Faulty cable can give VU signal (and only records noise) always used headphones. Senheiser HD25 is very good at hambientes noisy.

A good ploy I use is to record the right channel at half the level of the left. So if anything is too hot on the left, I use the right channel recording.

Having said that my Alphatron just arrived so I'm living in the land of the *safe* now, being also able to have meters for the audio coming off the camera. Yes to this, no to my wallet being slimmer.

Jules

S
ALL of my audio is blown out.

So, does anyone know if there is *anything* I can do with blown audio? Pretty sure I know the answer, but I thought I'd ask just in case...

Maybe this can fix it http://www.izotope.com/products/audio/rx/
You can download a free trial and have a stab at it - worth trying out.

Make sure you download the advanced version.


good luck, Frank

Sean, you can send me a download link and I can try restoring the clipped audio.
Usually I can do it, as long it did not clip to the extremes.

Sean, you can send me a download link and I can try restoring the clipped audio.
Usually I can do it, as long it did not clip to the extremes.

I doubt it, but I appreciate any help you can provide.

https://www.dropbox.com/s/pi1rrdd4zumkh ... _C0000.wav

That is why I don't use the audio from the camera.
It's hard enough to record good audio.
But when you are not confident in what you are recording……

Sean, I tried two different restoration approaches.
You can download them here:
http://www.loom.at/~loomdata/private/lbk/SCM_BMCC_1_2_2013-09-23_1438_C0000_repaired.rar

I would say, the audio is now at least usable, but don't expect a miracle, as it was really severely distorted (but you knew that ). I did my best to repair it.

After shooting on DSLRs for years and knowing the audio limitations of recording audio on those...

Even they have VU meters. The lack of VU meters or some indicator of audio level on the BMCC, especially given the ease of implementation* is sickening. That said, I never record audio without listening on headphones (at least a bit). I've found the Sennheiser HD202s to be quite loud on the BMCC's headphone jack.

Speed skills (and we all make mistakes), sorry to hear about your difficulty Sean.

*ML's source code is publicly available.

Thanks a lot Robert! I like the first version. I'm surprised how much you were able to clean it up!

Frank, that's pretty powerful software, I played around with the file for a couple hours. I couldn't get it as clean as Robert, so I might use his version if I can edit it down to only use the clean bits but thank you for posting that software!

Thanks a lot Robert! I like the first version. I'm surprised how much you were able to clean it up!

Glad I could help
I know how annoying such a mistake can be.

After shooting on DSLRs for years and knowing the audio limitations of recording audio on those, l've just made it a habit of always backing up the audio with a small external recorder like a H4N in addition to on the BMCC too. It is such an easy to do back up. I guess I don't know exactly what you are shooting but that recorder and a split can fit in your pocket or a tiny shoulder bag so it should be a simple thing in most cases.

I have been using DSLR with Zoom H4n being the field recorder (main audio) and on-board mic as back-up.
I have a question: is the pre amp of H4n (which sucks) better than BMCC's? When you plug in a self-powered directional mic (like Rode NTG2), dial level all the way up, on which one you get more gain/louder audio? I could barely use H4n + NTG2 combo, but thinking of getting BMCC + NTG2 (xlr to jack cable) without pre amp.
Anyone had experience with this combo?

Frank, that's pretty powerful software, I played around with the file for a couple hours. I couldn't get it as clean as Robert, so I might use his version if I can edit it down to only use the clean bits but thank you for posting that software!

Yeah, nothing beats experience and craft.

BMCC audio has a few issues. I finally got a monitor that shows audio levels, and I discovered that, due to the DC offset of the BMCC recording process, it shows a modest audio 'level' with no audio. This complicates the meter reading, but I got used to it, and I can use it. Even so, I still rely on the headphones and knowing where to set my preamp for normal levels. To me, the headphones are invaluable. You can catch other audio problems as well as clipping. Yet we all know that there is nothing quite so reassuring as looking at an audio meter when checking audio levels.

It still boggles my mind that BMD have not yet done anything about the audio issues. They could garner so MUCH goodwill with just a small amount of code, it defies belief that they have not done it. I am aware of the one audio 'upgrade', which I decline to use.

One thing about it, when you get 'burned', it etches it in your mind for the future, eh?

dn

BMCC audio has a few issues. I finally got a monitor that shows audio levels, and I discovered that, due to the DC offset of the BMCC recording process, it shows a modest audio 'level' with no audio. This complicates the meter reading, but I got used to it, and I can use it. Even so, I still rely on the headphones and knowing where to set my preamp for normal levels. To me, the headphones are invaluable. You can catch other audio problems as well as clipping. Yet we all know that there is nothing quite so reassuring as looking at an audio meter when checking audio levels.

It still boggles my mind that BMD have not yet done anything about the audio issues. They could garner so MUCH goodwill with just a small amount of code, it defies belief that they have not done it. I am aware of the one audio 'upgrade', which I decline to use.

One thing about it, when you get 'burned', it etches it in your mind for the future, eh?

dn

Yes, yes it does!