Why buy a mixer?

[Richard Crowley]

OK Richard. The noise stays the same. I get that. Going back to my pre mod VX2100 - I set it to mic, and plugged in a mic - definite noise there. Then I set it to line, and everything turns down but feeding a louder +4db signal from my line level mixer results in a better signal to noise ratio.

The noise is still there, but the S/N ratio is better. So in one's final recording it sounds like less noise. I heard it. If there was no difference they wouldn't put the option there.

OK, so you are using an external mic preamp to increase the signal level (not to reduce the noise). And that has the effect of making the SNR larger. That's fine.

But the next question is: why do we need extra external gain to get a decent level? Is the director not letting us get the microphone close enough? Are we using a mic that is not sensitive enough for the job? Is the actor not speaking or projecting properly?

Now increasing the gain externally may be the proper solution to a problem. But I would certainly suspect that something was fundamentally wrong somewhere else before I settled on that solution. I would want to check for broken bones before simply applying a bandage.

They put the option there because we must record line-level audio sources, and it is convenient to not have to carry around an external pad. If we must always use extra external gain, then something else is wrong and we haven't resolved the basic issue.

 

[Gohanto]

OK, I challenge you to cite a recent production video camcorder at any price that has genuine line-level inputs, NOT simply switchable pads ahead of the mic preamps. My $5,000 Sony DSR-300 does not have real line inputs, and I have yet to see ANY camcorder that does. At any price.

Audio has always been an afterthought with video equipment designers, and it probably will always be. They know that users who really need high-quality audio are going to use double-system sound and never depend on the camcorder tracks.

RED and HVX.

Even if they do use the cameras preamps, I've shot and done tests with both of them. The S/N ratio was better with a mixer with each camera and going line-in. Whether that's technically "possible" doesn't really matter to me. I just go with what sounds best (along with the other reasons to use a mixer like riding gain, more than 2 mics, better limiters, ect...).

 

[Chadfish]

RED and HVX.

Even if they do use the cameras preamps, I've shot and done tests with both of them. The S/N ratio was better with a mixer with each camera and going line-in. Whether that's technically "possible" doesn't really matter to me. I just go with what sounds best (along with the other reasons to use a mixer like riding gain, more than 2 mics, better limiters, ect...).

Yes. Though Mr. Crowley is technically correct about the noise being the same noise whether its at Mic or Line level, he seems to be missing the big picture that the guy just wants less noise ratio in his signal. Going in at line level with a clean mixer will always sound less noisy than going in at mic level straight from the mic, given the camera he has and the practical implementation of the advice given.

 

[Richard Crowley]

RED and HVX.

Even if they do use the cameras preamps, I've shot and done tests with both of them. The S/N ratio was better with a mixer with each camera and going line-in. Whether that's technically "possible" doesn't really matter to me. I just go with what sounds best (along with the other reasons to use a mixer like riding gain, more than 2 mics, better limiters, ect...).

RED does not have real line-level inputs. They are switchable just like everyone else. Furthermore, they are switchable by software control which makes the audio path even more suspect than lesser camcorders with mechanical switches. RED has a pretty poor reputation for audio in professional production audio forums. My own encounter with one left me underwhelmed.

I would be truly astonished if HVX has real line-level inputs that bypass the mic preamp. Where are the separate line-level inputs?

 

[Richard Crowley]

Yes. Though Mr. Crowley is technically correct about the noise being the same noise whether its at Mic or Line level, he seems to be missing the big picture that the guy just wants less noise ratio in his signal. Going in at line level with a clean mixer will always sound less noisy than going in at mic level straight from the mic, given the camera he has and the practical implementation of the advice given.

He probably wants MORE S/N ratio

There is no technical or logical reason why feeding line level through a pad into the same mic preamp will "always sound less noisy". If we have a problem with inadequate level from running a mic into the camcorder mic preamp, then that is an issue in itself that should be addressed. Using additional external gain (as from an external mixer) is one possible workaround for that problem. I must disagree that using an external mixer is some kind of magic solution for a gain/level problem.

Simply using an external mixer to fix a gain/level problem leaves me with a chronic case of wanting to find the REAL problem to solve it vs. using a mixer as a workaround.

Are there actors that mumble and whisper? Sure. Are there microphones that naturally have low output? Yes. Are there situations where we can't get the mic at the ideal distance? Certainly. Are there camcorder mic preamps with low gain, yes again. Are there lousy camcorder mic preamps that have congenitally poor SNR, alas.

Is using an external mixer one possible solution to any of these problems? Yes. Is it the only solution, probably not. Will a mixer always sound less noisy than using a mic straight into the camcorder? No.

 

[justmarvin]

Interesting discussion guys!

So from what I've gathered, the discussion seems to be leading to that a Mixer hooked up to the camera does not improve the sound by itself (it has the same noise because the camera does not have pure line level...and the mixer can even introduce more noise to the picture in some circumstance?). What a Mixer can do is increase the Signal to Noise ratio by making the signal level higher, and in a situation where the signal to noise ratio is bad like when the microphone is too far from the actor, then this will help, but this can also be resolved without a mixer by getting the mic closer. Is this right?

Also, the Audio knobs on the DVX100b, does that increase the Signal to noise ratio any? Or is that just increasing/decreasing volume? Probably with more volume there is more noise?

Richard, you recommended this brand for a mixer:

If I do need a production mixer one of these days, I'm willing to take a chance on something like this... http://www.signvideo.com/fpamxr.htm

Would you let me know what model is comparable to the Sound Devices 302? They look more comparable to the Sound Devices 442 or 552, and I think the Sound Devices 442 / 552 might be a bit overkill for my needs. Just want to make note so I can follow this brand's mixers as well like if they update their model.

And what would be a good separate recorder to look into?

Thanks,

Marv

 

[Chadfish]

JustMarvin

If your camera can switch to line level, and you use a line level mixer like any Sound Devices, you will have a final audio file that sounds better than if you just plugged the mic straight into the camera w/camera set to mic level. That's with all things being equal as far as mic placement. You will have less noise. Don't get confused by all the tecno-babble.

You may get a cleaner recording going into a separate recorder. That depends on the recorder. If your recorder has line level inputs, you will get a better recording going through a Sound Devices mixer - if the recorder's mic inputs are not stellar.

If your camera is recording HDV - you basically are recording a 320kbps mp3 file. That is a limitation of the HDV codec. One really wants uncompressed audio for serious projects.

With recording into any mic preamp, the quality of the mic preamp is what is important (along with good technique). A sound devices mixer's mic preamps are usually going to be better than the mic pre on a camera.


Separate recorder? On a budget try the Oade Brothers Modified Edirol R-44. Very clean, very light, 4 channels. 1,050.00 or so.

http://www.oade.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=OBA&Category_Code=EDIR44-Concert

 

[Richard Crowley]

Interesting discussion guys!

So from what I've gathered, the discussion seems to be leading to that a Mixer hooked up to the camera does not improve the sound by itself (it has the same noise because the camera does not have pure line level...and the mixer can even introduce more noise to the picture in some circumstance?). What a Mixer can do is increase the Signal to Noise ratio by making the signal level higher, and in a situation where the signal to noise ratio is bad like when the microphone is too far from the actor, then this will help, but this can also be resolved without a mixer by getting the mic closer. Is this right?

Yes, an external mixer can be used to increase the signal level, but the fact that the signal level needs to be increased is the underlying problem. Using additional gain may or may not solve this fundamental problem depending on what is causing it.

Also, the Audio knobs on the DVX100b, does that increase the Signal to noise ratio any? Or is that just increasing/decreasing volume? Probably with more volume there is more noise?

Virtually all active audio equipment has a "sweet spot" typically somewhere between 40% and maybe 70% of the range. Running the level/gain below that risks decreasing your signal-to-noise ratio (SNR). Also called running "down in the mud" (i.e. noise).

Running above that risks distortion from hitting the upper limits of the equipment's dynamic range, i.e. "clipping" and/or analog stage distortion. If you find yourself setting ANY audio level way low or way high, it is time to question whether something is wrong with the equipment or the configuration.

Richard, you recommended this brand for a mixer:

Would you let me know what model is comparable to the Sound Devices 302? They look more comparable to the Sound Devices 442 or 552, and I think the Sound Devices 442 / 552 might be a bit overkill for my needs. Just want to make note so I can follow this brand's mixers as well like if they update their model.

And what would be a good separate recorder to look into?
Marv

To be clear, I did not recommend that mixer, I said that IF I were to acquire a production mixer (which I have NOT needed so far), I would consider that model. The professionals over on r.a.m.p.s weren't very impressed by that mixer, primarily based in its low price (since likely none of them had heard or used it.) Generally, you get what you pay for. But there are some "sleepers", equipment that performs far better than you would expect from the brand or specs or price. And if you understand the technology, you can often work around limitations and get away with using less expensive equipment.

It isn't clear that you NEED a mixer at all here? You haven't really told us what kinds of projects you want to equip yourself to be shooting? It seems more likely to me that your $$$ would be better spent on a few more kinds of microphones so that you will have a variety to choose from. For example you should have at least one clip-on lav (and maybe two). And I would think that a decent wireless transmitter/receiver (decent means at leasts $500) would seem like a much bigger necessity for a well-rounded sound kit than an external mixer.

I do not in any way apologize for the "techno-babble". Unless one understands the actual technical situation (and terminology) one is stuck with "indy-sound audio-lore" which seems less than accurate, at least from what I have seen here so far. Perhaps because I am both an engineer and an audio (and video) producer, I am dissatisfied with workarounds and audio lore.

 

[DrDave]

If I was going to use a mixer, I would have one made or buy one with a true summing buss. But I just use the totalmix in the RME. I'm just saying, regardless of the differences of digital and analog mixers, or true summing mixers and so on, I never buy or bring a mixer because if I need one, my RME andFF400 and 800 and Digiface all have mixers built in with every feature imaginable including MS, plus half of the other stuff that I haven't even tried the built in mixers. But every now and then, they are useful, I juts use them maybe once a year at this point, for odd situations where they just fit the bill. There certainly are plenty of good used ones around, however. I can't see using a mixer to reduce noise per se unless there is a mismatch in the gear at some point, and even then I would be more inclined to use a mic pre with variable impedance if I wanted to fine tunethe mic to the pre.

 

[Guy_Cochran]

Interesting discussion. We wound up testing the Sign Video ENG-44 with a matched pair of condenser mics. We wanted to see if a typical camcorder's line input with a simple mixer sounded better than just sending the same mic directly into the camera. Here is the results in this video. http://www.youtube.com/watch?v=kaJS5UtDtBk

Mic - RODE NT1-A
Mixer - Sign Video ENG-44
Camera - Panasonic HPX-170

IMPORTANT NOTICE: No media files are hosted on these forums. By clicking the link below you agree to view content from an external website. We can not be held responsible for the suitability or legality of this material. If the video does not play, wait a minute or try again later.

I AGREE

 

[Chadfish]

I have to say that it was tough to hear a difference. I'm leaning towards the mixer adding a tad more high end detail evidenced in the cymbals ringing on the Dave Mathews recording. Still pretty close. Of course the camera is high end, and has nice preamps. Things may be different with a lower end camera.

 

[Guy_Cochran]

I have to say that it was tough to hear a difference. I'm leaning towards the mixer adding a tad more high end detail evidenced in the cymbals ringing on the Dave Mathews recording. Still pretty close. Of course the camera is high end, and has nice preamps. Things may be different with a lower end camera.

The mixer does sound a tad, just a tad, bit better, with additional detail in the lows, but we're talkin' a really, really fine discrepancy between the two. The reason for the test was to hopefully reveal something much more dramatic. I wanted "whoa amazing" shock and awe and got "I can't hear the difference."

I need to go back into the studio and perform the same test using the Panasonic HMC40 or similar $2000 camera with both the ENG-44 and something more high-end, maybe a Sound Devices 302 or my new Kamesan KS-T2000.

 

[justmarvin]

Nice video demonstration Guy.

I also didn't get the "whoa amazing" difference in the sound.

I need to go back into the studio and perform the same test using the Panasonic HMC40 or similar $2000 camera with both the ENG-44 and something more high-end, maybe a Sound Devices 302 or my new Kamesan KS-T2000.

Sound Devices 302 would get my vote for the next test

JM

 

[Matt Gottshalk]

Nice video demonstration Guy.

I also didn't get the "whoa amazing" difference in the sound.



Sound Devices 302 would get my vote for the next test

JM

That is the small mixer by which most other are judged...and for good reason!

 

[Chadfish]

Hey Guy.

One suggestion when comparing a music file. Try going back and forth between choices without back tracking to the same point. That method is great for testing voice, but with music you can hear the quality difference much better if the file just plays through. The sonic quality of each section in the song remain the same for 4 or 8 bars, before you get into a chorus or something, so if you switch mic sources while the music continues you will hear any change more evidently, as if you were A/Bing a plug-in sound while mixing music in a studio.

Does that make sense?

Like: Mic A - You've got your ball you've got your chain (Switch to Mic B) Tied to me tight tie me up again...

You did do that a little, but I found it jarring to go back to the same starting point. That jarring sort of erased the sound of the first mic to where I didn't feel the difference.

As a side note, I hate that one can't do anything in FCP without playback stopping. It's the continuous play while inserting/removing certain filters that gives one a real feel of the change.

OK - off to fight the crowds at Costco to save 60.00 on a 32" HDTV...

 

[Richard Crowley]

Thanks, Guy. Perhaps when testing audio equipment, since the audio track is the part of interest, posting uncompressed WAV files (or lossless FLAC) would be sufficient. If it is important to see the setup a few still shots (frame grabs) would likely suffice. And a live instrument, even a badly played guitar, sax, trumpet, piano, etc. would be a better test than listening to a recording on speakers (unless you are doing it in a controlled environment like an anechoic chamber. etc.

Nevertheless, a useful experiment, thanks for sharing it with us. I must say that I thought the direct sound was ever so slightly cleaner and more transparent than through the mixer. However, there wasn't 1% worth of difference between them. Very unlikely to be discerned in the final mix in any case.

As a result of hearing how clean the ENG-44 is, I submitted an order to DVEstore for the mixer and the Rode NTG-3 kit. Assuming I am getting in on the $1 blimp deal (for Nov-Dec)? I must have missed the killer Black Friday sale prices at your store! ) Just kidding. Happy to support a DVXuser sponsor.

I am going to be needing another shotgun and a battery-op field mixer for some anticipated ENG and "reality"-like EFP next year. Essentially equipping another "production unit"

I can't imagine how the Kamesan (with one fewer input!) can possibly sound $900 "better" when the ENG-44 sounds that transparent. Transparency (not "sounding BETTER") is the holy grail of audio technology, at least during acquisition. If you want to apply effects to the audio (or the video, for that matter) in post-production, THAT is the proper step. Where you can hear/see what you are doing. Not during the heat of production.

 

[Fresh Meat]

I try so hard to cram all of this knowledge

I try so hard to cram all of this knowledge

Hello All,

I'm very new to the whole indi production world.

I have read several books concidering many topics of pre- production- and post. To name a few:

Shut Up and Shoot / Anthony Q. Artis
Making Documentary Films and Videos 1st and 2nd editions / Barry Hampe
Producing Great Sound for Film and Video 3rd edition / Jay Rose
Audio Postproduction for Fil and Video 2nd edition / Jay Rose

I find these book very helpful and interesting.

Now I am in the process of gathering togther all of the equipment I (think) I will need to do a doc in China.

The only people involved in my first production so far are my wife and myself.

My BIG question is............

How would you sound experts rate the Sound Designs 788T with CL-8 controller ?
I have been doing research for some time now and this seems to come out on top.

I do understand this is over kill for most shoots. I'm not concerned about the budget as I am fortunate in that dept. I like to be prepared for any eventuality.
But I am concerned about getting the best possible sound. I agree with many things I have read. You can have the best pictures and direction, but if your sound sucks, you have nothing.

From what I have learned so for from actual experience and study..........I will never put sound on a camera if It can be avoided. maybe run and gun.

I doubt I will ever be in that situation.

Thanks for reading my long post.

 

[Richard Crowley]

Hello All,

I'm very new to the whole indi production world.

I have read several books concidering many topics of pre- production- and post. To name a few:

Shut Up and Shoot / Anthony Q. Artis
Making Documentary Films and Videos 1st and 2nd editions / Barry Hampe
Producing Great Sound for Film and Video 3rd edition / Jay Rose
Audio Postproduction for Fil and Video 2nd edition / Jay Rose

I find these book very helpful and interesting.

Now I am in the process of gathering togther all of the equipment I (think) I will need to do a doc in China.

The only people involved in my first production so far are my wife and myself.

My BIG question is............

How would you sound experts rate the Sound Designs 788T with CL-8 controller ?
I have been doing research for some time now and this seems to come out on top.

I do understand this is over kill for most shoots. I'm not concerned about the budget as I am fortunate in that dept. I like to be prepared for any eventuality.
But I am concerned about getting the best possible sound. I agree with many things I have read. You can have the best pictures and direction, but if your sound sucks, you have nothing.

From what I have learned so for from actual experience and study..........I will never put sound on a camera if It can be avoided. maybe run and gun.

I doubt I will ever be in that situation.

Thanks for reading my long post.

No question that Sound Devices is a charter member of the top-tier makers of production audio equipment today and a very well respected brand name in the industry. You could hardly do better at any price.

The only downside of using equipment like that might be that may distract/detract from more important aspects of capturing good documentary sound, especially with a 2-person crew. The 788T is designed for complex professional production and it does very well at that from all reports (I do not have one). Unless you or your wife already have experience doing production sound, it may be a bit much to handle for simple sound acquisition.

More important than the recorder is using a microphone that suits each particular situation. As you say, you need to be prepared for any eventuality. If I had that kind of budget I would rather spend it on a good microphone kit so that I had shotguns (with booms, windscreens, etc), hypercardioids (for indoor use), hand-helds (for quick interviews, on-camera, stand-up "reporting"), a few clip-on lavs (for sit-down interviews), etc.

You may have developed a distorted impression of recording sound to the camcorder depending on which discussions you have read here (or in other forums?) There is nothing fundamentally inferior about recording sound to a camcorder, assuming that it has a decent audio section. You didn't mention what camcorder(s) you plan to use, but if your generous audio budget is any indication, we would assume that you are using camcorder(s) with decent sound sections.

Particularly for small-crew documentary shooting in less-than-ideal conditions (unfamiliar territory, undeveloped countries, etc.) I would place higher value on flexibility, simplicity, and traveling light. If I had to carry the entire sound kit in a backpack (which I have done), I would prefer to have a much smaller (lighter) field mixer, a selection of microphones, mic accessories (windscreens, booms, stands, etc.) and cables. And headphones for monitoring OF COURSE! (Two pair, at least, and a few "ear-buds" just for backup or "stealth")

In my experience, it will make a much bigger difference to the final product to have a person keeping the proper microphone in the right place than having a high-end digital mixer/recorder. This is based on your stated mission of producing small-scale documentaries. If you said you were shooting film-style scripted drama or "reality" with a dozen mics, that would be a very different matter. A $6K mixer/recorder won't do you any good if you have the microphone too far away, or aimed the wrong direction, etc. OTOH, a $25 mic in exactly the right place plugged directly into the camera can produce "broadcast-quality" results. "Broadcast quality" in quotes, because current practice (reality shows, "shaky-cam", MTV, etc.) has eroded the value of that phrase.

Likely 100.00000% of the news footage and probably 90% of the prime-time documentary sound you hear was recorded on the camcorder and not a separate sound recorder. When using a quality camera with only one or two microphones in a small-scale documentary, any kind of separate sound recording scheme is not just overkill, but possibly distracting from the primary mission.

Whatever you select to use, certainly plan on a few weeks (or months, if possible) to become familiar with the equipment so that it becomes a secondary issue to the primary production decisions and execution. For audio (or video, for that matter), consider hiring a professional for a few sessions of one-on-one training. It would probably be worth getting someone with a well-equipped kit to come for a few hours and show you all the components of a good working equipment kit. Nothing like hands-on, especially with an experienced professional.

If you don't remember anything else from Mr. Rose's excellent books, remember that using a microphone ON THE CAMERA is probably the WORST possible choice and the absolute last resort. If I had to chose between using the 2nd person of the crew to "mix" vs. "boom" it isn't even a horse race. No amount of "mixing" or high-end digital recording can rescue bad sound from the on-camera mic.

And certainly keep reading online forums like this one, and asking questions. Consider starting a new thread just for your situation (vs. tagging on to this one). You could call it "Doco Sound 101" or something catchy. Best of luck with your endeavors. Sounds like challenging fun.

 

[Rippie]

Likely 100.00000% of the news footage and probably 90% of the prime-time documentary sound you hear was recorded on the camcorder and not a separate sound recorder. When using a quality camera with only one or two microphones in a small-scale documentary, any kind of separate sound recording scheme is not just overkill, but possibly distracting from the primary mission.

This is a little silly.
You say it's overkill and distracting, but how about the fact that the camera man is now untethered and can be free to worry about the picture. Same with the soundmixer. If the cameraguy is on a long lens the soundmixer can move to wherever he/she needs to be to capture the audio required.

Of course you can achieve the same thing with a wireless hop to camera, but
suddenly you put the burden on the camera man to listen to your audio and alert you of issues. Thats distracting, not to mention the soundmixer just never knows for sure if his audio is getting recorded to camera perfectly.

So most people with wireless hops end up doing a backup safety recording anyway. So why not do it as the primary. Any camera that has a decent audio section worth recording to also has timecode in/outs. Just jam the 788T
and the camera and you're good to go.
With of course superior sound going to the 788T compared to ANY highend camera, you also now have 12 tracks to do whatever you need.
Even if its 3 mic's you can have a 2 track mix and 3 iso's for later.

Sure everything you say can be done with camera audio and work out just fine,
but if you're trying to take things to another level other than "acceptable"
then double system for doc's is a great way to go.

 

[Richard Crowley]

This is a little silly.
You say it's overkill and distracting, but how about the fact that the camera man is now untethered and can be free to worry about the picture. Same with the soundmixer. If the cameraguy is on a long lens the soundmixer can move to wherever he/she needs to be to capture the audio required.

Of course you can achieve the same thing with a wireless hop to camera, but
suddenly you put the burden on the camera man to listen to your audio and alert you of issues. Thats distracting, not to mention the soundmixer just never knows for sure if his audio is getting recorded to camera perfectly.

So most people with wireless hops end up doing a backup safety recording anyway. So why not do it as the primary. Any camera that has a decent audio section worth recording to also has timecode in/outs. Just jam the 788T
and the camera and you're good to go.
With of course superior sound going to the 788T compared to ANY highend camera, you also now have 12 tracks to do whatever you need.
Even if its 3 mic's you can have a 2 track mix and 3 iso's for later.

Sure everything you say can be done with camera audio and work out just fine,
but if you're trying to take things to another level other than "acceptable"
then double system for doc's is a great way to go.

All true but the most important issue is getting (and keeping) the right microphone in the right place. Who is doing that while the first person is shooting and the only other crew person is "mixing"?

The finest mixer on the planet and the best digital recoder known to mankind will NOT rescue poor sound from the wrong microphone or the incorrect application of even the proper microphone. THAT is the primary issue with acquiring decent sound, particularly given the starting situation of the OP. I still say that unless/until the primary issue is addressed all else is secondary at best. Now the OP may already have a great collection of microphones and knows how to use them to best advantage, but he didn't mention it here.