[Ty Ford]

I just spoke with this other studio engineer friend of mine, and he mentioned to me that although ideally you want to have your average highs at tone (which is -12db’s on my FCP and digital camera meters), that an audio meter scale and the levels that you set depend on the RANGE of that audio meter scale.

**Your language “average highs” is confusing. Let’s get specific. All audio is comprised of RMS (root mean squared) and Peaks. RMS is equivalent to average. Different meters may or may not indicate both. Both are important; especially peaks readings. Peaks of -12 are OK with really good gear. MOST camcorders are not that good. If you peak at -12 on MOST camcorders and then reset and record with peaks at -5, and listen carefully, you will hear the diffference in noise. I’ve done this with a PD150. The hiss level at the lower record level was obvious.

**The RANGE of the audio meter scale is very important. There is a horrible lack of meterig standards in the industry today, especially with prosumer cameras. What’s important is knowing where -20 dB is and where 0 is. Theoretically, you can set tone at -20 and use the dynamic range all the way to 0. Continuous tone doesn’t have peak content, BTW. So, after setting tone at -20, expect most of your audio to be well above -20 if your meters read peak.

**Different people have different RMS to peak ratios in their voices. Setting levels properly and riding gain requires vigilance. Good audio is not “set and forget.”

For example, the audio meter on Final Cut Pro ranges from 0 to about -96. My engineer friend (not the same person who is working on my film) said that this means that zero is at about 96 db’s, and that an average reading of -24 to -30 db’s on a scale of 0 to -96 db’s is very acceptable. My friend mentioned that -30db (on a scale of 0 to -96) would be able 66 dbs, which is loud enough to increase the gain and not have artifact issues.

** “Zero is about 96dB” What does that mean? SPL (sound pressure Level) measurements and equipment level measurements both use decibels (dB) as a unit of measurement, but they are different. What you don’t know, is whether the 0 to -96 are really decibels or just some range the manufacturer decided to use.

What are your thoughts about this?

Are audio levels relative based upon what the range of that scale is? Does -24/-30 on an audio meter scale of 0 to -96 sound like a good level?

**Without knowing how good your gear is (camera mixer, mics) — how noisy they are — the only way to tell is to compare different record levels for noise as I mentioned above.

**The -15 peak recording I make on a Sound Devices 744T will be quieter than a -15 peak recording on any camcorder on the market. Why? Because even the most heralded camcorder makers spend their money on the picture and not the sound.

**Further, what you hear in the headphone output of a camcorder may not be what’s on the tape because many headphone circuits in camcorders are horribly noisy. You really have to get the audio out of the camera to be able to make really good comparisons, assuming the other gear you have has better noise specs.

**And don’t get me started on HDV audio, which isn’t even 16-bit, 48 kHz audio to begin with. It’s MPEG.

Regards,

Ty Ford

Ty Ford’s “Audio Bootcamp Field Guide” was written for video people who want better audio. Find out more at https://www.tyford.com

[Ty Ford]

1) That as long as the audio “sounds” good to the ear (through headphones or through studio speakers), then that is the main judgment of whether audio levels are o.k. (and not a meter). He said that perhaps someone at an academic institution might recommend “going by the book,” and setting levels strictly by an audio meter, but that most audio engineers will go by how the audio sounds to them. (He did say, however, that the audio must NOT peak the meter, however.)

**Headphones rather than meters can be deceiving, depending on where they are plugged in. Posing that only academics go by the book is pure crap. “Audio Peaking a meter” is an unclear choice of words. My meters show peak all the time. What you don’t want is audio that exceeds 0dB.

2) He said that with a very good mic and in a quiet setting, that it is possible to raise the gain of a DIGITAL audio signal with no hiss or artifacts. (Personally, this goes against what I have been taught, that you set audio levels to the higehst level possible without peaking– By the way, I like the two mono audio channel approach that was mentioned in this thread, with one channel being set slightly lower than the other).

**Yes this is true. I have a Neumann TLM 103. In my studio it’s extremely quiet. Quiet enough to record at a lower level and survive being raised without increasing the noise floor too much.

3) He also said that during a sound mix of the film, that he will not be focused on mixing the audio at a certain level (except that it does not peak), and that during my final level output adjustment when the film is going to take is when I should set the final overall level so taht it does not go past zero.

**Sounds reasonable.

Thanks again for your thoughts and feedback on this. I am also copying and pasting your comments to him (and the second audio guy) in an email so that they and I can have a good, definitive discussion about this.

**If there’s enough other sound to cover any noise that might be there, it’s a moot point, almost. There is an issue of decreased definition because lower record levels mean fewer bits are used and those bits are all about resolution, but as I said before, with really good converters, preamps and low noise mics, you’ll probably not hear any noise if that track is in a mix. If it’s low in the mix, the odds are you’ll never hear the noise.

Ultimately, it’s the ears that count. Different ears are sensitive to different things. It’d bug me to record dialog that low, but not percussion tracks in a music mix that I knew would be low in the mix. Maybe this guy has an airtight, anechoic studio with mics that have a selfnoise of less than 9 dB-a. You can get away wih a lot with that sort of stuff. Most studios DON’T have that luxury.

Regards,

Ty (non-academic) Ford

Ty Ford’s “Audio Bootcamp Field Guide” was written for video people who want better audio. Find out more at https://www.tyford.com

[Ty Ford]

First, are we talking peak or RMS?
Second, today’s digital audio recorders in 24-bit mode CAN do wonders. Not all of them, but some.
This excludes camera audio.
Third, depends on the sound. If it’s dialog, you want that up front. Peaks at -3dB down to -14 dB on a dedicated professional recorder will be OK, but camera audio is a lot noisier and the lower voices and sound will be in the noise floor. Bring up the level and you’ll also bring up the noise.

I purposely recorded audio with -35 dB peaks on a Sound Devices 744T and normalized the files to 100%. Yes there was some hiss, but less than you’d have gotten with an analog tape recorder. I was pretty impressed.

If the Music and SFX are prominent enough, you’ll probably get away with it because they will mask the system noise and ambient sound around the dialog.

Regards,

Ty Ford

Ty Ford’s “Audio Bootcamp Field Guide” was written for video people who want better audio. Find out more at https://www.tyford.com

[Ty Ford]

Hi,

When I looked, the Panasonic you mention only has mic level inputs. The Sound devices MixPre https://www.sounddevices.com/products/mx2master.htm

only has Line Level outputs.

That means you’ll need to knock down the output of the MixPre to mic level or you’ll over drive the camera input.

Regards,

Ty Ford

Ty Ford’s “Audio Bootcamp Field Guide” was written for video people who want better audio. Find out more at https://www.tyford.com

[Ty Ford]

29.97/23.976 = 100/x

Where X is the percent 23.976 is of 29.97.

So, 23.976/29.97 x 100 = the percent you want.

Regards,

Ty Ford

Ty Ford’s “Audio Bootcamp Field Guide” was written for video people who want better audio. Find out more at https://www.tyford.com

[Ty Ford]

What’s interesting is that, while many locations sound guys/gals refer to the cmc641 as a hypercradioid, Schoeps defines it as a supercardioid.

“increased directivity either for the sake of a

[Ty Ford]

Whoa Neighbor!

The hypercardioid is quite usable in interiors. I use a Schoeps cmc641 in interiors all the time. You need to be closer than 2 feet. I like to be within 16 inches of the person’s head unless we’re in a very dead room. You are correct about shotguns, though.

For a quick tutorial, go on over to my website and download the mic tutorial video.mp4. It’s a 12 minute crash course in why to use which mic.

Go to http://www.tyford.com
click on the OnLine Archive atop column #2
Click on the Video folder and download
Ty Ford Mic Tutorial VIdeo.mp4

Enjoy,

Ty Ford

Ty Ford’s “Audio Bootcamp Field Guide” was written for video people who want better audio. Find out more at https://www.tyford.com

[Ty Ford]

Pretty much. What sort of work are you doing and what do you hope to do?

Mics attached to cameras are pretty limiting.

I’d start with a Sennheiser G2 wireless, a Countryman B6 wired with THE LINK so that it can be used hard wired or plugged into the Sennheiser.

I’d get a Rode NTG-2 with wind protection and a 9-12 foot carbon fiber K-tek boom.

I’d get a Sign Video ENG-44 mixer and a set of Sony MDR 7506 headphones.

Regards,

Ty Ford

Ty Ford’s “Audio Bootcamp Field Guide” was written for video people who want better audio. Find out more at https://www.tyford.com

[Ty Ford]

Good for you! It’s been my experience that electronic equipment with connections can be serviced simply by disconnecting and reconnecting various things. Schmutz builds up on contacts and causes nutty things or non-operation. By disconnecting and reconnecting you scrape the schmutz off and everything works again.

If only this were true of our brains and hearts.

Regrds,

Ty Ford

Ty Ford’s “Audio Bootcamp Field Guide” was written for video people who want better audio. Find out more at https://www.tyford.com

[Ty Ford]

Hi Bruce,

There was an issue with early internal power harness cables in the 002. Mine died and they sent me a new one. User replacement is not impossible. One end of the cab;e (its plug) was a bit difficult to detach, but after that, it was pretty was pretty easy.

Contact digidesign about it. It is a free replacement.

Regards,

Ty Ford

Ty Ford’s “Audio Bootcamp Field Guide” was written for video people who want better audio. Find out more at https://www.tyford.com