(Successful post-production requires solid production. Here is one in a series of production tutorials designed to improve the ultimate edit.)

The oft-stated yet still under- appreciated reality is that audiences will forgive mediocre video but not sub-standard sound. Solid audio recording offers better choices in post-production, and separates your work from that of an amateur.

Listed below are the steps to set up an external condenser microphone, a basic field mixer and a prosumer camcorder – specifically, audio-technica’s AT8035 Line + Gradient Condenser Microphone, Sound Devices’ 302 Compact Production Mixer and Canon’s XH-A1 high definition camcorder - to capture audio in the field.

(Note: Photos are to illustrate the hardware, and may not contain accurate settings. Please follow the written instructions below rather than rely on the photos).

QUICK CHECKLIST
All the details are below, but here is a quick checklist:

1. Plug the AT8035 mic and a set of headphones into the 302 mixer.
2. Plug the 302 into the A1 camcorder.
3. On the 302, select MIC and PH, and set the Phantom Voltage Selection switch to 48V.
4. On the A1, set the LINE/MIC switch to LINE and the input channel selection switch to CH1 (or, if you prefer, CH1/CH2 - see discussion below). Then set the +48V switches and the XLR MIC ATT. switches to OFF.
5. On the 302, flip the Slate Mic/Tone Switch to 1K to generate a tone, and adjust the CH1 and CH2 audio dials on the A1 so that the tone measures between -20 dBFS and -12 dBFS, (depending on the dynamics of the audio and the levels of other clips that may be added to your piece). Turn off the tone generator.
6. On the 302, turn the Fader to 0 and the Gain all the way down. Set the Pan Switch to C, the Polarity Reverse Switch to OFF and the High-Pass Filter to the center position. Turn the Headphone Volume all the way down and set the Headphone Selector Switch to 1.
7. Point the AT8035 at the sound you want to capture, and slowly increase the Gain control on the 302 until the Output Meter peaks between 0 and 6 dBu. Then, slowly increase the Headphone Volume to your comfort level.
8. Depress the Gain control knob, and repeat the above procedure for each mic you may be using. Use the Fader to mix the relative level of all the inputs.

Getting Wired

Pop batteries in the 302 and flip the Power switch (lower right) to INT. Run a cable from the AT8035 to the 302’s XLR input. Select the level (MIC or LINE) and powering (PH, DYN or T-POWER) on the 302 that matches your mic. The AT8035 is a condenser mic that uses phantom power, so select MIC and PH, respectively, and set the Phantom Voltage Selection switch to 48V. Finally, plug a set of headphones into the PHONES input.

FYI GUY
European-made “T-powered” mics require the T setting. Mics that do not need power, like dynamic mics, use the aptly-named DYN setting. Check the 302 manual for info on voltage issues, so you do not damage your equipment, or yourself.

Next, run two XLR cables from the 302 to the XLR inputs on the A1. (See picture at top of article). Then, set the switches above the XLR inputs on the A1: the XLR MIC ATT. switches to OFF; LINE/MIC switch to LINE; and the input channel selection switch to CH1/CH2.

To attenuate (or lower) the volume received from the 302 on either or both channels, you can change the XLR MIC ATT. switches to ATT. – but this function only works when the LINE/MIC switch is set to MIC.

If you have two audio sources (e.g. two mics plugged into your 302 mixer), then you may want to set the input channel selection switch to CH1, thereby sending the CH1 input to Channel 1 on the camcorder, and the CH2 input to Channel 2 on the camcorder. This allows you to independently control the levels for each channel. In our case, CH1 and CH2 have the same audio source – the AT8035 plugged into the 302. Thus, you can chose to set the input channel selection switch to CH1/CH2 so that both CH1 and CH2 inputs are delivered to both Channel 1 and Channel 2 on the camcorder. This allows you to adjust the levels simultaneously. However, good habits should be formed early, and splitting the signal to Channels 1 and 2 will leave you with one less thing to remember when you start using 2 or more mics.

The 302 is factory-set to output at LINE level, which is why you should set the LINE/MIC switch to LINE. In addition, the +48V switches on the front of the A1 should read OFF. If you unplug the 302, and plug a microphone directly into the A1, then you can change the LINE/MIC switch to MIC level and, if that mic needs phantom power, set the +48V switches to ON.

Leveling Off
Now that you’re wired up, you need to verify that the 302 is speaking at a level that the A1 is expecting, and that your mic is speaking at a level that the 302 is expecting.

AVOIDING “MIXED SIGNALS”
Imagine a schoolgirl listening intently as her friend tells a secret. She leans closer and closer, ears cupped, eagerly anticipating a salacious tidbit about the new, cute boy in homeroom. Her friend slowly opens her mouth and . . . SCREAMS AS IF ON THE OTHER SIDE OF GYM CLASS. Or maybe she IS on the other side of gym class, and whispers as if standing a foot away. Under either scenario, the sound suffers because the person receiving the signal is expecting a level different than what the source is about to deliver.

The 302 is factory-set to output at LINE level – that is, its native level without any attenuation (or lowering). However, if the light on the 302 Output Panel labeled “OUT ATTEN” is illuminated, then the factory settings have been modified to attenuate the output. (Refer to the 302 Manual to reset the factory defaults.)

You have already set the LINE/MIC switch on the A1 to receive LINE level. This is particularly important when using the A1 because this camcorder insists on amplifying every signal it receives – a function that cannot be disabled. Thus, when the A1 receives a signal at MIC level, it will amplify the signal to LINE level. Reasonable, right? Sure, but even if the signal is already at LINE level, the A1 will attenuate the signal just so that it can apply its own amplification. A tad duplicative, but there it is. (Some would argue: Why not just set the mixer and XH-A1 to mic level so that, again, you have one less thing to remember when you connect a mic to the camera directly? It’s a persuasive point, and you may want to adopt this method instead.)

Next, you’ll want to set the audio on the A1 to the appropriate level. Flip the Slate Mic/Tone Switch on the 302 Front Panel (upper right) to 1K, which outputs a factory-set 1kHz tone at 0 dBu. Then, adjust the CH1 and CH2 audio dials on the A1 so that the digital readout on the side panel of the A1 is between -20 dBFS and -12 dBFS. The LCD display on the A1 will also show the audio output, but the side panel display is more precise. (TIP: Is your A1 ignoring the XLR input? Press the MENU button on the A1, navigate to AUDIO SETUP, select XLR INPUT and set it to ON.)

Once you’ve got your dials set, flip the 302’s Slate Mic/Tone Switch back to MIC. Before you move on, rip yourself off a nice piece of gaffer’s tape and cover the audio dials on the A1 so they don’t move. You will applaud yourself later for such foresight.

FYI GUY
To help avoid blowing out your ears, the 302 automatically attenuates, by 20dB, the 1kHZ tone delivered to your headphones. Another reason to rely on the digital display rather than your ears to set the A1 dials.

Now that the 302 and the A1 are speaking the same aural language, you should adjust how the microphone is talking to the 302. Set the Fader on the 302 (that’s the larger knob) to “0” (i.e. 12 o’clock or the “unity” position) and turn the Gain all the way down. Set the Pan Switch to C (for Center) and the Polarity Reverse Switch to OFF.

You can experiment with the High-Pass Filter to see whether you want to hear all the low frequencies (center position), or whether you’d like to reduce certain low frequencies – either those that reach 160 Hz or those that only reach 80 Hz. Finally, turn your Headphone Volume all the way down and set your Headphone Selector Switch to 1 (for Input 1).

Syballance
Let’s pause for a moment to reflect on what is finally about to happen: You will utter those storied words, repeated for decades by audio engineers who have graced stages both lowly and epic in grandeur: “Check 1, 2. Check 1, 2.” As you repeat this historic mantra - or more accurately, as your subject provides you with some test audio - slowly increase the Gain control until the 302’s Output Meter peaks between 0 and 6 dBu. Then, slowly increase the Headphone Volume so that you can hear, as well as see, the levels. Once you are roughly satisfied with meter readings on the 302, depress the Gain control knob so that you don’t inadvertently change the levels. (No gaffer’s tape required!) You have established the “pre-amp” input – i.e., the level that the 302 receives from the microphone. Switch the Headphone Selector Switch back to “ST” for stereo, so you can see and hear the mixer’s output. Now you can use the Fader to mix the relative level of all the inputs. (Lucky you, you’ve only got the one.)

By following these steps, you will receive cleaner and more robust audio in the field – something for which you will be continuously thankful in post.

By Rich Volin - DCFCPUG.org
with contributions by Marty Atias of ATS Communications
Photos by Eric Kemp (used with permission)