Some Audio Testing Results

[Fergus Meiklejohn]

10s, lets have that debate after you have had the opportunity to shoot with the RED, as I'm not buying this argument...

Deal?

But I'm going to have to buy the camera to find that out.. That's why I'm asking.

Finner's question is spot on.


My opinion is not that there IS a problem. But with no limiters, no audio pots, a reasonable but not stellar noise floor, and no definitive tests or opinions on how much noise the camera, lcd, and Red Drive make and can be picked up by a shotgun mic mounted on the camera, when they've been recording for 60 minutes non stop.. :innocent:

Stuart: You must agree that there is room for doubt here, or a least not knowing what you people at RED know, there is room for doubt in my mind..

And I guess I'm spending my time going on and on about it, because for me: no sound=no camera..:umm:

 

[10s]

10s, lets have that debate after you have had the opportunity to shoot with the RED, as I'm not buying this argument...

Deal?

Since a debate won't shed much light on useability let's do this: Let's have those who have the camera run some tests and report back. Mine will be available in a few months so I'm depending upon dispassioned observation and expermentation to shed light.

I'm hoping the camera design will not limit me to a prescribed style of film making. ENP &/or Cinema Verite, while not my usual cup of tea, is something I expect professional equipment to support.

So here's a very simple test: Plug in your fav mic, attach it to the camera, set levels so you can capture quiet conversation, walk into a small crowd of people talking quietly and see what the results are.

The test should tell us a number of things, among them I can think of a few things I'm interested in:

1. How the camera does with a mic nearby with high gain settings. Does the camera produce more than normal noise, Does it vibrate and send sound through it's body to the mic?

2. Adjusting levels on the move, is it easy? Can you adjust the levels while it's on your shoulder or will it inhibit a "run & gun" doc style?

3. Internal noise level, signal/noise acceptable? Is it clean enough, no buzzes, fan noise, etc.

4. Limiter: is it needed or not? Do those occassional bumps and meter spikes cause clipping?

5. Can the camera function with one person or does it require a crew. How easy is it?

6. Add your own questions, etc.

Hopefully the camera will excel in all areas. I have no need to put this camera down, and on the other hand I have no need to overlook any shortcomings.

 

[Finner]

I believe there is a better way to accomplish this test.

First find a room that is as close to silent as posstible. Put a red drive on the camera, THEN:

Set up 1) Put a person on a chair 10 feet in front of camera. Shot gun mic on camera in channel 1, Lav mic on person in channel 2 and a shotgun on a boompole in channel 3. Set all mics to the correct level at the persons normal voice level. Hit record and have the person speak for a while at normal level then slightly louder then quite a bit louder then slightly quieter then normal then a lot quieter then normal and finally not saying anything. Then send that person home.

Set up 2) Attach the boom pole to a C-stand, put the lav mic on yourself hit record grab a book and sit down in front of the camera and read in silence for 45 minutes.

Test 1 should give results for the three most common mic set ups in a controled environment. Test two should help us see how much noise the camera makes and if the fan gets louder over a long take.

**DISCLAIMER** I am by no means a sound guy. In fact sound was the department I liked least in film school. So please sound GURU pro's add any key information needed.

So who has a camera/red drive and is ready to take up this test?

 

[philper]

I believe there is a better way to accomplish this test.

First find a room that is as close to silent as posstible. Put a red drive on the camera, THEN:

Set up 1) Put a person on a chair 10 feet in front of camera. Shot gun mic on camera in channel 1, Lav mic on person in channel 2 and a shotgun on a boompole in channel 3. Set all mics to the correct level at the persons normal voice level. Hit record and have the person speak for a while at normal level then slightly louder then quite a bit louder then slightly quieter then normal then a lot quieter then normal and finally not saying anything. Then send that person home.

Set up 2) Attach the boom pole to a C-stand, put the lav mic on yourself hit record grab a book and sit down in front of the camera and read in silence for 45 minutes.

Test 1 should give results for the three most common mic set ups in a controled environment. Test two should help us see how much noise the camera makes and if the fan gets louder over a long take.

**DISCLAIMER** I am by no means a sound guy. In fact sound was the department I liked least in film school. So please sound GURU pro's add any key information needed.

So who has a camera/red drive and is ready to take up this test?

I'm ready to help test drive Red audio with me and my gear anywhere in the SF Bay Area, if we can work out the schedule.

Philip Perkins CAS

 

[10s]

I believe there is a better way to accomplish this test.

First find a room that is as close to silent as posstible. Put a red drive on the camera, THEN:

Set up 1) Put a person on a chair 10 feet in front of camera. Shot gun mic on camera in channel 1, Lav mic on person in channel 2 and a shotgun on a boompole in channel 3. Set all mics to the correct level at the persons normal voice level. Hit record and have the person speak for a while at normal level then slightly louder then quite a bit louder then slightly quieter then normal then a lot quieter then normal and finally not saying anything. Then send that person home.

Set up 2) Attach the boom pole to a C-stand, put the lav mic on yourself hit record grab a book and sit down in front of the camera and read in silence for 45 minutes.

Test 1 should give results for the three most common mic set ups in a controled environment. Test two should help us see how much noise the camera makes and if the fan gets louder over a long take.

While your test woud be good for a number of observations, the testing I suggest will uncover the ability to use "in-action" on the shoulder with varying audio levels. This will test setting the levels. Is it easy to perform compared to other cameras? (including our dear old DVX & HVX friends) does the camera need a limiter? and noise issues, etc...

I woud think the camera should easily perform well in these conditions but from some postings listed there seems to be some concern. The more valid data that Jannard & team get from users will help them conduct needed course corrections in the design and production of this wonder weapon.

 

[Finner]

While your test woud be good for a number of observations, the testing I suggest will uncover the ability to use "in-action" on the shoulder with varying audio levels.

Control is always the key basis for testing. Nailing down the the basics of the audio quality is the first step and how it is effected by varring talent voice volume levels and camera noise. Walking into the middle of a large group of people will not reveal any real results.

This will test setting the levels. Is it easy to perform compared to other cameras? (including our dear old DVX & HVX friends) does the camera need a limiter? and noise issues, etc...

I can answer this right now. In a situation like you mention The camera will be more difficult to adjust audio then any other camera on the market and yes it will need a limiter.

The camera has no audio pots! This means audio will all have to be done inside menu options. So in a situation like you mention If you did not set your level bang on before you walk in to that crowd you will have to take it off your shoulder re-adjust the level and then start shooting again. There will be no mid shot adjustability without pots like other video cameras. Keep in mind though that this is a cine camera and with the way the audio has been engineered it can not be treated like an ENG camera and will not work well in an ENG situation like you mention.

Please note for those that wish to point out that it is an ENG camera please take a look at the red web site They call it "RED DIGITAL CINEMA" not "RED DIGITAL ENG".

 

[JFirestone]

The camera has no audio pots! This means audio will all have to be done inside menu options. So in a situation like you mention If you did not set your level bang on before you walk in to that crowd you will have to take it off your shoulder re-adjust the level and then start shooting again. There will be no mid shot adjustability without pots like other video cameras. Keep in mind though that this is a cine camera and with the way the audio has been engineered it can not be treated like an ENG camera and will not work well in an ENG situation like you mention.

I wonder how feasibile it would be to create a USB based audio control system for this camera. It's the first time any camera company has created such a flexible system, and by having the USB peripheral port, could theoretically allow external audio pots at some time down the road.

 

[10s]

I can answer this right now. In a situation like you mention The camera will be more difficult to adjust audio then any other camera on the market and yes it will need a limiter.

The camera has no audio pots! This means audio will all have to be done inside menu options. So in a situation like you mention If you did not set your level bang on before you walk in to that crowd you will have to take it off your shoulder re-adjust the level and then start shooting again. There will be no mid shot adjustability without pots like other video cameras. Keep in mind though that this is a cine camera and with the way the audio has been engineered it can not be treated like an ENG camera and will not work well in an ENG situation like you mention.

Please note for those that wish to point out that it is an ENG camera please take a look at the red web site They call it "RED DIGITAL CINEMA" not "RED DIGITAL ENG".

Finner nice answer. I love Cinematic cameras but I also love advancement. Given what you say about the design being Cinematic rather than ENG, I think RED failed to take advantage of ENG design. I wish they would have valued the advantage video had over film was the ENG ability (i.e., a news gathering situation: quick, chaotic, loud, unorganized...) to record decent audio. While the audio quality may not be the best, it is often good enough.

This dependence on dual system and external gadgets (that will eventually make the camera too heavy, clumsy and unusable) is a limitation and therefor it's a set back.

Unfortunately the DVX and HVX, and many other video cameras, appear to be more flexible for many audio situations than RED. There is a better design philosophy for RED to embrace in which all user/production styles win.

Once they get it right....watch out!

 

[donatello b]

"Also when the fan kicks in in silent mode how quiet is it?"

i don't know about other REDS but 103 :
the silent mode is very quiet .. however the next level up is NOT that quiet for interior home type locations - IMO the soundman is going to ask for a sound blanket over the camera ...
RED 103 experience = 50-55 degree weather my Red stays in quiet mode ( it might have the fans running at higher speeds when not recording but it does turn to quiet fans when i hit record ...

56-64 degrees - it all depends on the mood of 103 that day & time ???

interior 68 degrees !! red 103 goes out of quite mode after about 20 min .. when i hit record the fans remain same level .. i can switch to all other fan modes and it does NOT go down ... you can tell me it should go down BUT i have the camera in front of me and it does NOT going down ...i can restart , reload firmware etc and it remains the same ..

will be shooting on Sat with soundman - interior, live in loft location - i'll let you know what the soundman says ....

 

[Fergus Meiklejohn]

"Also when the fan kicks in in silent mode how quiet is it?"

i don't know about other REDS but 103 :
the silent mode is very quiet .. however the next level up is NOT that quiet for interior home type locations - IMO the soundman is going to ask for a sound blanket over the camera ...
RED 103 experience = 50-55 degree weather my Red stays in quiet mode ( it might have the fans running at higher speeds when not recording but it does turn to quiet fans when i hit record ...

56-64 degrees - it all depends on the mood of 103 that day & time ???

interior 68 degrees !! red 103 goes out of quite mode after about 20 min .. when i hit record the fans remain same level .. i can switch to all other fan modes and it does NOT go down ... you can tell me it should go down BUT i have the camera in front of me and it does NOT going down ...i can restart , reload firmware etc and it remains the same ..

will be shooting on Sat with soundman - interior, live in loft location - i'll let you know what the soundman says ....

Brilliant Donatello, thank you.

Lots of people on REDuser were worrying about having no audio pots in the middle of last year. We were told not to worry...:sarcasm:
My hunch is that RED were so busy fixing the picture, they took their eye off the audio. It's totally understandable.

If the camera can't do interior interviews for longer than 20 minutes because the fans kick in, it has limited use for ENG, EFP production IMO
If the non control of audio levels and no limiters means the audio is often distorted, then again it has limited use for ENG, EFP production..

There are a few thousand people worldwide making features, and tens of thousands, maybe even a hundred thousand people worldwide doing EFP work. That is something Sony do understand..

 

[Finner]

Given what you say about the design being Cinematic rather than ENG, I think RED failed to take advantage of ENG design.

I raised a lot of posts months ago trying to get red to see the value of audio pots but unfortunately it was not seen as valuable.

 

[Finner]

Brilliant Donatello, thank you.

Lots of people on REDuser were worrying about having no audio pots in the middle of last year. We were told not to worry...:sarcasm:
My hunch is that RED were so busy fixing the picture, they took their eye off the audio. It's totally understandable.

If the camera can't do interior interviews for longer than 20 minutes because the fans kick in, it has limited use for ENG, EFP production IMO
If the non control of audio levels and no limiters means the audio is often distorted, then again it has limited use for ENG, EFP production..

There are a few thousand people worldwide making features, and tens of thousands, maybe even a hundred thousand people worldwide doing EFP work. That is something Sony do understand..

If there is no way to shut off loud fans it will be a huge issue. EFP interview will be very dificult and last time I checked silent films were not becoming the blockbusters, not for the last 80 years anyway.

Your sound experience on your shoot will be very interesting to hear about.

 

[John K]

We did quite a bit of testing on the audio yesterday with camera #232, and have come to some conclusions.

As has been reported there is a hiss. (In the original tests we did.)The hiss was only there when phantom power was enabled. When using line level, or when using the battery on the mic with mic level, there was no hiss. (I haven't been able to replicate those results so I retract the statement that it was definitely tied to phantom power.)

The headphone out is reversed from what the manual states it should be for us as well.

.

Regarding the hiss, that sort of problem can be caused by an inadequately rated blocking capacitor on the mic preamp input. With ordinary dynamic or electret mics there's usually no voltage across this capacitor, so virtually any sort of low-voltage part will work fine. However if you plug it into a socket incorporating phantom power, that will apply 48 Volts or so and then it's a different story!

Usually though, the input either doesn't work at all, or you get severe distortion. I suppose it depends on the part they used, if this is in fact the problem. It's an easy mistake for a engineer to make if he hasn't had experience with pro audio.

 

[John K]

If there is no way to shut off loud fans it will be a huge issue. EFP interview will be very dificult and last time I checked silent films were not becoming the blockbusters, not for the last 80 years anyway.

Your sound experience on your shoot will be very interesting to hear about.

I always thought a good idea would be to have some sort of "dead man switch" that could use to temporarily disable the fan while you're shooting critical scenes. ("Dead man" meaning that you could only do this by actively holding the button in). There would be no latching function, so you couldn't accidentally leave the fan switched off. OR you could have it so that it does latch, but made so that the fan would come back on as soon as you stopped "rolling".

Alternatively, the switch could temporarily bump up the fan's thermostat so if the camera started to overheat badly, it would over ride the switch.

 

[10s]

I always thought a good idea would be to have some sort of "dead man switch" that could use to temporarily disable the fan while you're shooting critical scenes. ("Dead man" meaning that you could only do this by actively holding the button in). There would be no latching function, so you couldn't accidentally leave the fan switched off. OR you could have it so that it does latch, but made so that the fan would come back on as soon as you stopped "rolling".

Alternatively, the switch could temporarily bump up the fan's thermostat so if the camera started to overheat badly, it would over ride the switch.

Good idea for the fan. Of the many audio recorders that I have, there is one, a Korg D1600 that has the auto fan switching for recording takes. So when the user is setting up the fan is working but when an actual recording is engaged it goes dead. It works really well. Most of the fixes needed have already been invented and proven in working products throughout the world.

 

[conrad gaunt]

I don`t have my camera yet, so I no reason to doubt the audio, but if there is an internal hiss problem, this might help ->
If one of the channels is set to record, but isn`t recording anything (ie, no mic plugged in), it will effectively be recording the cameras internal noise, won`t it? This channels recording of the background `noise fingerprint` could then be used (quite effectively in my past audio experiences) to remove this noise from the other channels. It seems to me 24bit audio will give us a lot of latitude in post to clean up the signals. Its obviously much better to reduce any internal noise in the first place, but these thoughts comfort me.
It would be nice if the camera had a dsp processor built in that could clean signals up in real-time, by sampling background noise, then removing it from all channels if needed (since internal noise will likely always effect all channels.

 

[thomas]

tc-audio vs. analog-audio delay

tc-audio vs. analog-audio delay

hi all

also did a test with the new red camera for a tv series, especially to test
timecode ability and analog inputs. the setup was:
red camera (software build 13)
sd744T (latest software version)
ambient clock it
25fps pal, 4k recording on the camera
camera jam synced with 5pin lemo
audio was sent to input 1 on the red camera, directly from sound
devices

then the whole tests were imported into final cut studio (fcp6), and
synced

RESULT was about 2 frames difference between audio directly sent to
the camera and the audio from the sd744t, delay seemed to be constant.

has anybody had similar experiences, does the camera have a delay on
the incoming audio?

what i also did not like at all: the camera is LOUD, even in silent
mode, and as i've read in another forum, after many hours of shooting, the
fan won't stop at all. has anybody tried to blimp the camera, did it
result in heat issues?

greetings

thomas

 

[Fergus Meiklejohn]

what i also did not like at all: the camera is LOUD, even in silent
mode, and as i've read in another forum, after many hours of shooting, the
fan won't stop at all. has anybody tried to blimp the camera, did it
result in heat issues?

greetings

thomas

Hey Thomas. Thanks for posting your experiences! Opinion is a bit divided around here about whether the camera is loud or not. Can I ask what your background is and what so what your definition of "loud" is please?
I mean: how quiet was the location? How long did you film for before the sound became noticeable? How warm was the room? How close was the camera to the mic? Could you imagine mounting a shotgun on the camera and getting usable sound? When you say "loud" do you mean like a laptop when it is ticking over, or a laptop when it is rendering? Does it compare to the distant rumble of traffic outside in a big city? Is it an annoying noise?


So many questions, sorry.. sound is so hard to define in words huh..

thanks


fergus

 

[Jochen Schmidt-Hambrock]

Unfortunatly without a proper measurement any answers to those questions are boardering on the meaningless.

The only thing I can say is that working without a battery using the charger as the powersource is out of the question in all but the most noisy environments.

Thats a pity because the thing doesn´t get hot at all.

Together with the camera fan being switched on after maybe 15 minutes it is definitly too loud for example for recording a classical concert. I really hope this is going to change.

Jochen

 

[Finner]

Jochen


What have you done for audio testing with your camera so far?