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Gear / Technical Help => Recording Gear => Topic started by: fleshoff on September 06, 2009, 10:45:53 AM

Title: audio for video
Post by: fleshoff on September 06, 2009, 10:45:53 AM
I have been directed to this forum by several sources so here goes...
I record audio using a shotgun on a boom going into my current video camera, this has been great and uncomplicated and am very happy with the audio. Unfortunately I am switching cameras to one that has auto gain control which can't be disabled...no good. I guess I need the external recorder option but of course am on a tight budget. The H4n has been the standard recommendation but even that seems too much in both money and features, maybe I'm dreaming.

I'm not using an XLR mic, it is the Rode VideoMic with 1/8th in jack
I really only need one track mono
I just want something that can record with that 1/8th in jack at something like 44-48 kHz and control the level going in. Would like to monitor via headphones while recording but not absolutely necessary (I can configure something if need be)

I have even experimented with my iPhone but I get clipping running into that with my shotgun, however if I could resolve that life could be good.

thoughts
galaxy audio hdr2
Dynasonic PDR-1
Title: Re: audio for video
Post by: George2 on September 06, 2009, 12:31:18 PM
Yes, people use the H4n, but the previous version had trouble syncing back to picture.
I've used the Edirol R-09HR at 48k and editor didn't have any problems.
Forget about those Galaxy or Dynasonic units.
Sonys look good.
Marantz PMD 620 would be good.
Fostex FR-2LE is good with video.

You get what you pay for.. there isn't any shortcut.

Title: Re: audio for video
Post by: willndmb on September 06, 2009, 04:37:33 PM
maybe its luck but i have had great success dubbing my fr2le to my canon mini dv
with that said does your new camera have mic/line in period? you just can't control the gain right
you might be better off getting some sort of attenuating cable and going directly into the camera
i have tried this 2 times recently and it came out good as a whole, with one more run  i'll have it perfect and save myself dubbing all together
Title: Re: audio for video
Post by: fleshoff on September 06, 2009, 07:46:32 PM
I'm getting a canon 7D which does have a mic in, it will be similar if not identical to the 5D I suspect with audio. Not familiar with an attenuating cable but would like to hear more.
Title: Re: audio for video
Post by: willndmb on September 06, 2009, 10:28:51 PM
I'm getting a canon 7D which does have a mic in, it will be similar if not identical to the 5D I suspect with audio. Not familiar with an attenuating cable but would like to hear more.
an attenuating cable cuts down the signal by _db (whatever its made for)
i have a -20db from microphone madness

so lets say you have the new camera and it has a fixed gain of 10db - the cable i have would cut the incoming signal down -10db from what it is
basically getting rid of the 10 db the camera adds and cutting it another 10
the extra 10 might or might not be a issue but you can always boost the signal in post production if need be

attenuators are "common" for taping out of a soundboard, there are many xlr version, the mic madness one i have is a 1/8
Title: Re: audio for video
Post by: fleshoff on September 07, 2009, 12:24:42 AM
But isn't this different than an automatic gain control which would I would suspect act somewhat like a compressor raising the quiet parts? I would think adding this cable would simply cause the AGC to raise the level of everything higher and thus raising the noise? I'm an audio dummy so if I'm ignorant please excuse.
Title: Re: audio for video
Post by: digifish_music on September 07, 2009, 08:46:12 AM

I'm not using an XLR mic, it is the Rode VideoMic with 1/8th in jack
I really only need one track mono
I just want something that can record with that 1/8th in jack at something like 44-48 kHz and control the level going in. Would like to monitor via headphones while recording but not absolutely necessary (I can configure something if need be)

I have used the Rode Video Mic with an Edirol R09HR on a 'prosumer' video shoot. Worked perfectly. Impressive sound from that rig.

I realise this is over budget, just a data-point.

digifish.
Title: Re: audio for video
Post by: willndmb on September 07, 2009, 10:42:12 AM
But isn't this different than an automatic gain control which would I would suspect act somewhat like a compressor raising the quiet parts? I would think adding this cable would simply cause the AGC to raise the level of everything higher and thus raising the noise? I'm an audio dummy so if I'm ignorant please excuse.
oh sorry i was thinking it had a fixed gain across all freq
Title: Re: audio for video
Post by: Carlos E. Martinez on September 07, 2009, 04:21:28 PM
Yes, people use the H4n, but the previous version had trouble syncing back to picture.

What problem was that? Sliding out of sync? A clock problem?
Title: Re: audio for video
Post by: digifish_music on September 07, 2009, 10:29:19 PM
Yes, people use the H4n, but the previous version had trouble syncing back to picture.

What problem was that? Sliding out of sync? A clock problem?

Possibly basic technique? Once you start separating the audio from the video (which is very common), clapper boards come in handy :)

I have never witnessed sync issues with the scenes I have worked on. 99% are less than 3 minutes. The main issue is aligning the audio aligned in the first instance after that it's always been OK for me. A hand-clap in front of the camera can be useful, you just align the remote audio to the camera audio clap-spike.

digifish
Title: Re: audio for video
Post by: willndmb on September 07, 2009, 11:22:07 PM
3 minutes is nothing though
typically when people have issues its after 30, 45, 60 minutes
the lag grows and grows and sooner or later you notice it
Title: Re: audio for video
Post by: sunjan on September 08, 2009, 05:00:33 AM
I guess I need the external recorder option but of course am on a tight budget. The H4n has been the standard recommendation but even that seems too much in both money and features, maybe I'm dreaming.

I'm not using an XLR mic, it is the Rode VideoMic with 1/8th in jack
I really only need one track mono
I just want something that can record with that 1/8th in jack at something like 44-48 kHz and control the level going in. Would like to monitor via headphones while recording but not absolutely necessary (I can configure something if need be)

thoughts
galaxy audio hdr2
Dynasonic PDR-1

IIUC, the Rode Videomic is powered by an internal 9V, so you don't have to rely on plug-in power at least:
http://usa.rodemic.com/microphone.php?product=VideoMic

The Dynasonic/Galaxy you mentioned have virtually zero field reputation, and the specs look dodgy:
http://taperssection.com/index.php/topic,106904.0.html

For the money, there are a lot better recorders to be had.
Cheap recorder with quality 1/8" mic in, decent gain and 44-48kHz?
iRiver H3x0 (from $60 used, but 44kHz only)
DR-07 (from $140 new)
MT II  (from $150 new, but mic-in is probably better on the DR-07)
etc...

The other recorders mentioned in this thread are of course even better, but all in the +$300 range (which you said you couldn't afford).
Title: Re: audio for video
Post by: fleshoff on September 08, 2009, 08:23:26 AM
Fantastic, thanks sunjan
Title: Re: audio for video
Post by: rastasean on September 08, 2009, 04:26:03 PM
Although its big and heavy, it does have a hypercard pattern and pretty quiet.

I'm speaking of the Rode NT3
http://usa.rodemic.com/microphone.php?product=NT3

There are XLR to 1/8" cables or one of these:
http://www.bhphotovideo.com/c/product/68657-REG/Shure_A95UF_A95UF_Line_Matching.html
Title: Re: audio for video
Post by: fleshoff on September 08, 2009, 04:29:43 PM
Thanks but I'm all good with the Rode VideoMic. I've been using it for about a year and want to stick with it.
Title: Re: audio for video
Post by: dallman on September 08, 2009, 05:48:23 PM
I'm getting a canon 7D which does have a mic in, it will be similar if not identical to the 5D I suspect with audio. Not familiar with an attenuating cable but would like to hear more.
an attenuating cable cuts down the signal by _db (whatever its made for)
i have a -20db from microphone madness

so lets say you have the new camera and it has a fixed gain of 10db - the cable i have would cut the incoming signal down -10db from what it is
basically getting rid of the 10 db the camera adds and cutting it another 10
the extra 10 might or might not be a issue but you can always boost the signal in post production if need be

attenuators are "common" for taping out of a soundboard, there are many xlr version, the mic madness one i have is a 1/8

It would seem like an attenuating cable into the iPhone would solve the clipping.
Title: Re: audio for video
Post by: fleshoff on September 08, 2009, 05:51:16 PM
Yeah you know I'm going to try that as I was liking what I got outside the clipping
Title: Re: audio for video
Post by: sunjan on September 09, 2009, 05:03:29 AM
It would seem like an attenuating cable into the iPhone would solve the clipping.

Yeah, but it doesn't mean that it'll sound good, depending on which way you feed the iPhone.
Going mono-in via the headset connector you'll be depending on third-party gear - some might clip, other not.
Read the discussion at the end of this page:
http://blog.faberacoustical.com/2009/iphone/iphone-headset-input-options/

Also, beware that the headset connector has a built-in bass roll off. Depending on iPhone generation, you might lose everything below 200Hz:
http://blog.faberacoustical.com/2009/iphone/iphone-dock-and-headset-io-frequency-response/

Going line-in via the dock connector, you have better accessories, but they'll likely cost you at least $50 (so you might as well get yourself a H3x0 for the money instead!  ;D):
http://taperssection.com/index.php/topic,118890.msg1663392.html#msg1663392
Title: Re: audio for video
Post by: fleshoff on September 09, 2009, 08:47:28 AM
Thanks I will do that if a solution isn't available once the camera comes. There is a hack for the 5D that might be very easy to port over to the 7D that disables the AGC, but no one will know until the camera is released, and that would make the whole issue moot for me. If not I will be buying one of the recommendations in this thread.
Title: Re: audio for video
Post by: milo on September 21, 2009, 05:09:58 PM
I just want to reiterate the need for a clapboard in frame.  Once your audio is recorded off camera life goes to hell without a timecode link between camera and recorder.  Seeing as how that is out of your budget, you need to do everything possible to allow easy sync up later on in post.  I really can't stress this enough.  I recently assembled a movie from DATs with no timecode, in Japanese (which I don't speak) and it was only possible due to their obsessive use of the clapboard, and nevertheless took a week.  Use it, or don't at your own peril, and make sure to voice slate everything that way you can marry it and forget that you ever had to work without timecode.
Title: Re: audio for video
Post by: willndmb on September 22, 2009, 10:44:10 AM
how does a clap board help you with drift?
of course it helps line up the start but can it do anything to help you in the video 30 mins lets say
Title: Re: audio for video
Post by: Toki on October 15, 2009, 11:10:12 AM
in sony vegas, you can find "claps" in both ends of your audio tracks, align the beginnings and then stretch the ends with a single mouse click for a perfect sync.