HD video recording - sound advice please?

G

GlynHugh

Suspended / Banned
Messages
49
Name
Glyn
Edit My Images
Yes
Hi there,

Never really used a DSLR for video before but thought I'd give it a go so I have asked to shoot a couple of gigs...nothing serious and not paying ones either so no pressure to perform! ;)

This will be for fun/experience only.

One will be a two person interview and the other will be a band playing on stage.

Gear will be a Canon 7D (I also have a Panasonic SDT-750 camcorder that I can press-gang into service if needed) and I have a Zoom H4N that I used to use to record some band stuff as audio only when I played at being a sound engineer for some friends.

My gut feel would be to get hold of a couple of lavalier mics for the interview and input directly into the H4N.

With the band I would usually take the main audio feed directly via the desk again into the H4N but also want to record from the floor to get the ambience & give more of a live feel.

How best to go about capturing these two very different kind of events please?

I always considered getting something like a Rode Stereo VideoMic Pro for the DSLR but have been put off by talk about hiss etc. which I could get away with when recording the band but probably not in the interview.

Might be OK for an improved audio track when out in the field doing general video stuff though without lugging around extra kit, cables etc...what do you think?

I would prefer not to play around too much in post-processing either if I can help it.

Two very different scenarios - one well lit & quiet, the other dark and noisy but hoping I can find a way to record both without resorting to two completely different setups.

Any hints/tips/gotcha's gratefully received.

Thanks & kind regards,
-=Glyn=-
 
Poor sound can ruin a good video. And it's probably just as dificult to get right as is the acutal video recording itself.

The Rode mike is a good bit of kit. I suspect that the comments about hiss come not from the mike but from the camera's preamp. I have a couple of mikes that I use with my 5D3. I use the manual controls for audio but still get a small level of hiss. Now this isn't normally audible via a laptop speaker, but on a decent system it is just noticeable.

Now take the same mikes and run them trough an Zoom H1 or H4 and the hiss is gone.

As far as recording is concerned I think your plan to get most of the Audio via the desk is a good one. Only problem will be mixing it with the audio you shoot to the camera. There will be a dramatic difference in quality due to the nature of the recording techniques. Syncing the two as well could be a problem if you don't want to spend to much time or money on the project.

Interviews I'd go with the Lav mikes.
 
One of the biggest mistakes you can make is to record something quietly where peaks are at -18dBFS when they need to be as closer to -3dB or very loudest at near 0dB (without clipping), you will only hear this difference in quality on playback only.
 
symmetricalOCD said:
One of the biggest mistakes you can make is to record something quietly where peaks are at -18dBFS when they need to be as closer to -3dB or very loudest at near 0dB (without clipping), you will only hear this difference in quality on playback only.
Click to expand...

Although I think most of this sentence would have gone over most people's heads (unless you have an understanding of audio), I don't think it is wise to advise people to record at close to 0dB (maximum volume you can record digitally for the uninitiated!). For that matter, even -3dB is pushing it.

Nowadays, there really isn't any need to record with that much 'headroom', as most modern analogue-to-digital converters are more than capable of capturing perfectly acceptable recordings without having to record the signal so 'hot'. The risk of ruining an otherwise perfectly good take is not worth taking for the sake of recording a theoretically better sound that 99.9% of people would not be able to tell the difference anyway.
 
GlynHugh said:
Hi there,

Never really used a DSLR for video before but thought I'd give it a go so I have asked to shoot a couple of gigs...nothing serious and not paying ones either so no pressure to perform! ;)

This will be for fun/experience only.

One will be a two person interview and the other will be a band playing on stage.

Gear will be a Canon 7D (I also have a Panasonic SDT-750 camcorder that I can press-gang into service if needed) and I have a Zoom H4N that I used to use to record some band stuff as audio only when I played at being a sound engineer for some friends.

My gut feel would be to get hold of a couple of lavalier mics for the interview and input directly into the H4N.

With the band I would usually take the main audio feed directly via the desk again into the H4N but also want to record from the floor to get the ambience & give more of a live feel.

How best to go about capturing these two very different kind of events please?

I always considered getting something like a Rode Stereo VideoMic Pro for the DSLR but have been put off by talk about hiss etc. which I could get away with when recording the band but probably not in the interview.

Might be OK for an improved audio track when out in the field doing general video stuff though without lugging around extra kit, cables etc...what do you think?

I would prefer not to play around too much in post-processing either if I can help it.

Two very different scenarios - one well lit & quiet, the other dark and noisy but hoping I can find a way to record both without resorting to two completely different setups.

Any hints/tips/gotcha's gratefully received.

Thanks & kind regards,
-=Glyn=-
Click to expand...

I think you've already got the right idea - lavaliers for the interviews and for the band stuff, a feed from the desk into the H4N. I would back up the desk feed with either a separate recording from the internal H4N mics, or the Rode Stereo mic, into the H4N (I'm pretty sure the H4N supports simultaneous four channel recording, but I might be wrong).

The idea of having the video mic in your kit bag, ready with your camera is ideal, regardless of noise issues, as it should be better than most on board mics in any case. For most applications, it's very easy with something like Audacity to filter the noise out if it's a problem.
 
symmetricalOCD said:
One of the biggest mistakes you can make is to record something quietly where peaks are at -18dBFS when they need to be as closer to -3dB or very loudest at near 0dB (without clipping), you will only hear this difference in quality on playback only.
Click to expand...

Utterly and completely totally garbage! Yellow is the new red in the professional world (of which I am part of for the last 25 years) ! Play safe and give yourself a decent headroom. Recording at digital zero is for foolish muppets who insist louder is better and know no
 
Dynamic range and noise floor. Your 16 bit recording device is way more capable than the quality of what you are recording in terms of noise floor and is capable of a dynamic range of 116dB. Your mic and mic amp are way inferior and have much worse noise floor. The only point of recording at digital zero is to use up the dynamic range and avoid any quantising noise. When have you heard dither or quantising noise? My guess would be never and when have you heard mic or mic amp hiss? Much more!
Asking a non pro on a raw unprocessed recording to peak at digital zero is like asking a new photographer like me to expose to the right on the histogram when the resolution of the lens is rubbish and it has no contrast and you have not much control of exposure - Asking for trouble and burnt out whites or in this case, digital distortion which is very hard to recover from.
 
The hiss you hear is because you are using automatic gain control, and when it doesn't hear much it whacks the levels up to max.

If you are shooting a gig, can you get direct audio from the desk? Assuming all of the instruments are connected and not acoustic?

Zoom H1 recorder is cheap and can record 24/96 not that you'll ever need to use that
 
A Blown digital audio recording is a nightmare to recover from - You can always boost a low signal in post....Thats my Rule on recording and I am no pro just a a joe who does a fair bit of recording....

Think Romulus and Remus...:lol:

Yellow is the new red:thumbs:


I recommend the ZOOM H4N as a great addition the tool box and especially using DSLR

However watch out taking a feed from a desk into the H4N unless you have a good way of reducing the signal into the zoom - cant think what I use now but its -20db inline from the desk - I prefer my own mics Senhiser K6ME66 I usually can deal with most situations with a pair of these and a couple of radio mic kits with lavalier and belt pack transmitters / receivers. Eliminates being subject to other peoples errors:lol:
 
MIKEROPHONICS said:
Dynamic range and noise floor. Your 16 bit recording device is way more capable than the quality of what you are recording in terms of noise floor and is capable of a dynamic range of 116dB. Your mic and mic amp are way inferior and have much worse noise floor. The only point of recording at digital zero is to use up the dynamic range and avoid any quantising noise. When have you heard dither or quantising noise? My guess would be never and when have you heard mic or mic amp hiss? Much more!
Asking a non pro on a raw unprocessed recording to peak at digital zero is like asking a new photographer like me to expose to the right on the histogram when the resolution of the lens is rubbish and it has no contrast and you have not much control of exposure - Asking for trouble and burnt out whites or in this case, digital distortion which is very hard to recover from.
Click to expand...

:thumbsdown::bang:
 
LASTOLITE said:
A Blown digital audio recording is a nightmare to recover from - You can always boost a low signal in post....Thats my Rule on recording and I am no pro just a a joe who does a fair bit of recording....

Think Romulus and Remus...:lol:

Yellow is the new red:thumbs:


I recommend the ZOOM H4N as a great addition the tool box and especially using DSLR

However watch out taking a feed from a desk into the H4N unless you have a good way of reducing the signal into the zoom - cant think what I use now but its -20db inline from the desk - I prefer my own mics Senhiser K6ME66 I usually can deal with most situations with a pair of these and a couple of radio mic kits with lavalier and belt pack transmitters / receivers. Eliminates being subject to other peoples errors:lol:
Click to expand...

:thumbsdown:
 
MIKEROPHONICS said:
Utterly and completely totally garbage! Yellow is the new red in the professional world (of which I am part of for the last 25 years) ! Play safe and give yourself a decent headroom. Recording at digital zero is for foolish muppets who insist louder is better and know no
Click to expand...


:thumbs:
 
I really couldn't put it better than this guy (who happens to be one of the most respected experts on sound in professional audio and broadcast).

This is taken from this thread on the Sound on Sound website:

http://www.soundonsound.com/forum/s...2194&Words=recording+level&topic=&Search=true

There are loads of confused and intermingled ideas here. Let me try to shed some light...


....2. Record at 0dB
The issue here is the widespread use of the decibel as an indicator audio level, but with an equally widespread confusion about the context it is being used in.

Digital systems generally have meters that are scaled with 0dB at the clipping level right at the top. This point should strictly be referred to as 0dBFS –the FS being shorthand for ‘Full Scale’ so that everyone knows the context that the term is being used in.

Analogue systems are generally used with meters calibrated in terms of dBu – the little ‘u’ indicating that the reference level is 0.775V rms. So a signal at 0dBu is one which has an average voltage level of 0.775V – it’s an analogue signal remember, and they are conveyed as varying voltages.

So if you desk has meters with a position marked as ‘0’ there’s a chance this refers to a signal level of 0dBu... Then again, it could be a ‘VU’ meter in which case 0VU could be scaled to almost anything you like, but is most commonly set to +4dBu (one important exception being on Mackie mixers when it is still 0dBu).

The important point to note here is that a signal peaking ‘0’ on the analogue desk’s meters is a very different thing to peaking ‘0’ on a digital system’s meters and that difference is ‘headroom’. All analogue systems have an (unseen) amount of headroom extending way above the metered ‘0’ point – typically 20dB or so. It’s that headroom margin that allows you to mix two dozen channels together without overloading the (analogue) mix bus.

So the analogue practice of peaking signals to 0VU – which is towards the top of the VU scale – still left a good amount of headroom above that to cope with transient peaks which were too fast for the meters to react to. You need to continue that practice into the digital domain, and that’s why it is normal to align the ‘0’ of an analogue desk to something like -18dBFS or -20dBFS.

To some that idea is disconcerting because it appears that signals only modulate the bottom half of the digital meter, and we’ve all been brought up with the idea that the meters should be bouncing around near the top. But the fact is that analogue meters don’t show the headroom margin, whereas digital meters do – and that headroom margin needs to be around 20dB for steady signals and maybe 10dB for transient peaks.

3. Don’t I want to record the strongest signal in my computer?
No. You want to record the cleanest signal into your computer. Two decades ago when we only had 16 bit digital systems you had to record fairly hot, simply to keep the noise low relative to the wanted signal. But we’ve had 24 bit systems for years now, and even the worst systems have a dynamic range capability that equals the best analogue could ever do, and some of it comfortably beast the dynamic range of an analogue console. So there is no need to record up to the end stops from a noise control point of view.

Instead, it makes much more sense to adopt the same kind of headroom practice as worked so well for analogue systems over the previous century – leave a notional 20dB of headroom to cope with the occasional transient peaks, and to accommodate the inherent level build-up when mixing a lot of tracks together.

When you’ve finished a mix the remaining headroom margin is no longer required, and as part of ‘mastering’ you can then remove that margin to allow your finished track to peak up to 0dBFS so that its peak levels match that of commercial CDs etc. But that is a separate stage in the production process.

Hope that helps

Hugh

--------------------
Technical Editor, Sound On Sound
Click to expand...

In summary, recording in the digital world at 0dBFS is a simply idiotic and outdated concept.
 
interesting read here,
i have recently got myself the Tascam DR-40, just started using it, and with that i can plug into mixing desk via xlr or jacks, and if i want i can also use the built in mics to record separately the atmosphere.
and to cover all bases i chuck an ext mic on the 5D3.

Keep the input levels below 0, no point in pushing the limits for volume and potentially dropping quality, after all your final output in you videos will not be pushed to its limit, keep it clean and let the final user turn their volume up if they so desire :-)
just my 2 pence worth, but then again im fairly new compared to some of the more experienced guys above!
 
Ah yes - Hugh RJ - an old colleague from the BBC

Inter sample peaks - the new dirty word in digital audio
 
The tax am dr40 is the best solution, it's got an underrated feature - it can record both at the level that you set, and another two tracks, xdB below the level of the main recording. Great last ditch backup / gives you options if sound levels spike for some reason and you clip.

Great bit of kit, I far prefer it to the zoom.
 
If the Zoom is 4 channel I'd use the desk feed plus two audience mics slung pretty high and not too far from the stage. I'd use "proper" mics, not the Rode

Might be wise to ask the mix engineer if he plays with the mix buss levels during the gig. If he does you might be able to take a pre-fader out to the recorder so your levels will stay the same

The band will definitely be louder toward the end of the gig than the soundcheck so allow some headroom

Nick Froome
 
But a peak near zero will have inter sample peaks over digital zero and therefore contain distortion when converted back to analogue.....if that is what you like?
 
symmetricalOCD said:
I'd like you all to tell me where I encouraged digital shred and clipping in my original post? it clearly states that you make the audio PEAK near 0dB but never over.
Click to expand...

The transient signal in your D/A converter will then peak over 0dB.

Wonder when R.128 meters will become available?
 
Last edited:
Available in what? And why a loudness meter? That has no relevance in a recording but in a transmission only.

Are you confusing intersample peak reading?

Stay 6dB shy of digital zero on a peak meter and you will be fine. Anyone who records any louder is demonstrating the art of distortion :-) yellows are the new red!

R128 meters for broadcast loudness measurement have been out over a year. See my review of Nugen VisLM in last september ( I think) audio media magazine (a pro read compared to the amateur basis for Sound on Sound)
 
MIKEROPHONICS said:
Available in what? And why a loudness meter? That has no relevance in a recording but in a transmission only.

Are you confusing intersample peak reading?

Stay 6dB shy of digital zero on a peak meter and you will be fine. Anyone who records any louder is demonstrating the art of distortion :-) yellows are the new red!

R128 meters for broadcast loudness measurement have been out over a year. See my review of Nugen VisLM in last september ( I think) audio media magazine (a pro read compared to the amateur basis for Sound on Sound)
Click to expand...

Note to self, sarcastic comments on all of the industry press reports need to be better phrased on the internet.
 
All you need to do is record your audio at 48khz and then import it into Soundforge or Adobe Audition etc and clean it up using hiss reduction.

obviously if its really bad hiss wise, you'll have to re-record it.

As far as a cheap Lav mic set goes, try this..... http://www.djstore.com/item/senfp12.htm
 
You must log in or register to reply here.
Back
Top