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Old June 10th, 2013, 01:42 PM   #1
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Who's eating my dynamics?

Hallo everyone!
I have a problem with my configuration Canon HF100 with Rode Stereo videomic.
I use this equip for amateur recording of live classical music performance.

BIG question: I put my mic, connected with a long cable to my hf100, 1,5-2mt (2 yards) far from sound source (string quartet or Violin and piano duo or violin solo)
What I get is a clear sound BUT absolutly I lost every dynamics of the performance...and my GF violinist everytime complains a lot :(

Ok so I put my mic at about 4-5mt (4-6yards) and i get back some dynamics but I get the eco sound too -_-"

Do you think Rode is eating my dynamics or is it my camera? Or both?
Any possible solution or mitigation?

Thank you
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Old June 10th, 2013, 02:07 PM   #2
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Re: Who's eating my dynamics?

Hello Giacomo,

You camera's AGC (automatic gain control) is adjusting the dynamics. To disable this, manually control the audio level using the Func/Joystick. You'll see a little picture of a microphone, and then you can dial in the level. See page 55 in the English manual: http://sils.unc.edu/sites/default/fi...ion-manual.pdf

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Old June 10th, 2013, 05:04 PM   #3
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Re: Who's eating my dynamics?

Ciao Giacomo, and watch the audio level meter carefully, so you don't overload the system.

From p55. As a guideline, adjust the audio recording level so that the audio level meter will go to the right of the -12db only occasionally.

Try the Videomic with its 10db pad *off* first till you see the record level is too loud.

And suggest you put the Videomic low frequency roll off *on* so you reduce any low room sounds which could affect the levels,
you might not hear that on headphones.

Christian, 'Brahams with Breakfast' in Sydney, nice job thx :)

Cheers.
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Old June 11th, 2013, 01:40 AM   #4
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Re: Who's eating my dynamics?

What a newbie!
Ok thank you a lot, I will try this manual config as soon as possible and I will give you a response!


My last recording, this was 4-5 yards away :D
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Old June 11th, 2013, 01:48 AM   #5
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Re: Who's eating my dynamics?

You need a white balance and tilt correction . . . .

HTH

Grazie
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Old June 11th, 2013, 02:02 AM   #6
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Re: Who's eating my dynamics?

and you need to get the mic off the camera and closer to the audio source.

Listening on headphones I can hear noises of you adjusting the camera, also a mic is not like a zoom lens and you need to get it closer to the players and not just place it where your camera is.

That rode videomic is OK but it is not the best mic to record classical music, it is far to wide and if you mono the audio a lot is missing due to phase errors.

I personally use a small sony ECM M/S 907 mic with my canon HF11 and it is small enough to place closer to the action.
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Old June 11th, 2013, 03:06 AM   #7
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Re: Who's eating my dynamics?

First thing really is that these are really good musicians, playing quality instruments, and the recording technique has robbed you of all the articulation and the detail in their phrasing. The focus has gone, and we're hearing the room. This is not a task you can do without some decent kit - and the equipment often has impact on the visuals. The little mic (well, it's not that small) is a bit less common, but in this case would do a good job. I'd probably use a cathedral stand - it's just a big boom stand that would let me place a couple of microphones centrally, just out of frame, looking down from a point about a metre/2 metres in front of them. As they're playing fairly close together, you could use an X/Y technique, or in that room, maybe M/S, and then have a bit more tweaking ability in the studio. The dynamics issue that annoyed the AGC means accurate level setting will be needed. Uo the topic a bit it was suggested that bass rolloff be applied. Indoors there is no noise to remove, and filtering off the bottom end will severely impact on the recording.

The main issue here is simply the mic being in the wrong place, meaning too much of the room and no detail from the musicians. This combination makes the instruments sound like student version, not what they really are. You can study Music Technology with A Level and BTEC, and grades wise this recording shows the traits many of the students accidentally exhibit. I don't usually subscribe to the often quoted "camera mounted mics are rubbish", but for music, they are.
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Old June 11th, 2013, 03:57 AM   #8
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Re: Who's eating my dynamics?

Well yes the mic is in the wrong place I know :(
But in this last recording I had no audio cable with me so I was forced to take mic with me too far away.
It was a sort of test too, because of the "flat dynamics" problem when the mic was close to them.

this is an older video , you can see my Rode on the left bottom corner, close to them at about 1,5mt, so you have evidence of the clear sound but no dynamics :D




Ok so I got the point about AGC and about white balance! I will try to tune them manually.
Thx Paul for your good technical explaination, I hope in the future to get some knowledge and some more equip to improve my amateur recordings.
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Old June 11th, 2013, 06:01 AM   #9
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Re: Who's eating my dynamics?

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Old June 11th, 2013, 07:16 AM   #10
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Re: Who's eating my dynamics?

I've been listening and looking at the audio in the closer miked version, and there's quite a bit of pumping as the AGC struggles to handle the music. It's also a rather harsh setting, it has fast attack and a fast release, so you often hear things you shouldn't - I'm not sure if it is a sniff, or clothes, or something else, but you hear it when a loud transient is followed by one of those up-bow flourishes. I think, however, the placement nearly works. It sounds nice. The viola is a bit lost, and 1st violin (your GF?) a bit OTT - but the cello sounds nice. The Rode mic has done a better job than frankly, I would have guessed. What got me confused a little is that although the stereo image seemed present, was that it seemed very narrow. I stuck it into my studio system and looked at it. The room is very live and the mic has captured that very well, but there's a 'hole in the middle'. The Rode spec info on their site is a bit rubbish - it simply says the mic is cardioid and shows a nice single cardioid polar diagram, so I can only assume this is the spec for one capsule, and in the X/Y format, they've probably gone for 90 degrees offset, so the 2nd violin and viola are in the null in the middle. This problem is pretty typical, to be honest, and lots of faffing around with mic placement is the key. Don't forget the stands are also pretty effective acoustic barriers. You could also perhaps experiment with their seating - perhaps just pulling out cello and 1st violin - a gentle curve rather than the fairly tight arc. The room probably sounds gorgeous, but it's very lively.

Next time - knock the AGC off, and be prepared to move things around in the rehearsal. If you really want to be difficult, you might also warn the audience that the recital is being recorded and enlist their help in giving you a little additional silence and the beginning and end.
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Old June 11th, 2013, 02:28 PM   #11
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Re: Who's eating my dynamics?

Yes she's my GF :)

After this kind discussion I think I can get some better recording even if my equip is not so good.
I would like to put the mic in a higher position to avoid standings problem, but no long bumper for me at the moment! Chairs Disposition was too "circular" and second violin and viola sound too weak....I know, but musicians do what they want and then complain with you :P
The location is an historical renaissance room in Florence, when it's empty musicians are scared about bad sound eco, when the room is full of people sound become amazing :D
https://docs.google.com/file/d/0Bwxq...it?usp=sharing


About Rode stereo videomic
http://wpc.660d.edgecastcdn.net/8066..._datasheet.pdf
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Old June 11th, 2013, 06:05 PM   #12
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Re: Who's eating my dynamics?

Ha being in the southern hemisphere is great, cleaner air, better light. But by the time you get on the site next day, 10 fellas up north
have posted after you lol.

Didn't get to see the Videomic pointed skwards, Giacomo you should lock it off tighter :)

Cheers.
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Old November 17th, 2013, 12:56 PM   #13
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Re: Who's eating my dynamics?

Hallo everyone!
I've done some new recordings...as you can see ther's NO WAY I can change their seats.
So There are always too strong cello/violin and too weak viola/violin
But mic close to them and AGC off have helped a bit.
What do you think? A bit better?
Thank you all


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