Audio Setup
The audio mixer box controls all the audio in the system. It has two
stereo inputs: the main input is controlled by the editor switch. The
secondary input is directly from the laserdisc player.
The master volume control (the blue knob) controls output audio level,
which is sent both to the speakers and to the audio inputs of all the
other components.
Audio Inputs
The four black knobs control the input to the mixer. When an
individual knob is pushed in, its input is connected through to the
output. When it is pulled out, it is not connected to the output but
it is connected to the mixer's headphone jack. Rotating the
knobs controls the relative volume of each input source. The pan knobs
should always be set all the way to the left for left audio inputs and
all the way to the right for the right audio inputs.
The first two knobs control the left and right stereo inputs coming
from the editor switch, the second two control the left and right
stereo inputs coming directly from the laserdisc player. Normally
the editor switch knobs should be in (i.e. connected), the
laserdisc knobs should be out (i.e. disconnected), and the volume
should be set to 10 on all knobs. Use the blue master control knob to
change the overall volume.
If you have already dubbed a voiceover onto a tape and want to add
music from a CD, you will then want to use the laserdisc inputs as
well as the editor switch inputs. Then adjust the individual volume
control knobs until the voice and music channels have the right
relative volume.
Recording a voiceover on your tape
Executive Summary
- Plug microphone into CH-1 microphone input.
- Set CH-1 audio level appropriately.
- Turn off Lyon Lamb and NTSC encoder.
- Turn off room ventilation system.
- Repeat until done
- Turn speakers all the way off.
- Hit DUB/CH-1 button to begin audio edit.
- Hit pause or stop when you mess up.
- Turn speakers back up to check the segment you just recorded.
- Cue the tape to the point right before you messed up.
- Turn the room ventilation system back on!!
Ambient noise
The video room should be as quiet as possible when
you record a voiceover on the tape, otherwise all the background noise
is also recorded which sounds quite tacky. Turn off the power on the
Lyon-Lamb scan converter (rightmost rack column, bottom (under the
table!), power switch on front) and the NTSC encoder (leftmost column,
under the table, power switch in back). These devices have loud internal
fans.
Important! The ventilation system for the video room is
quite loud, so you want to turn it off while making the voiceover. You
also want to shut the door. However, if the video room is unventilated
for too long the decks start to eat tapes. (Technically, if
humidity in the room gets too high, moisture condenses on the tape
heads, which causes the tape to stick to them instead of smoothly
rolling past. The air conditioning for the building is also a
dehumidifying system.) The ventilation system can take several minutes
to turn off or on. But the door is trivial to open and shut. So when
you're actually recording, have the door shut. When you're playing
back to see how it turned out, or thinking about what to say next,
open the door! Monitor the temperature in the room. If it feels really
hot or the thermometer goes above 72 degrees consider cooling the room
down before continuing. Do not forget to turn the air conditioning
system back on when you are done audio recording! (Turn the knob
to -4, which is maximum cooling.)
Microphone
A simple way to put a voiceover onto your tape is to use the audio dub
functionality of the play 3/4" deck. (The one on the left,
not the usual one you use for recording on the right!) The audio
DUB/CH-1 button allows you to record your voice into audio
channel 1 without disturbing the video track. Plug the microphone into
the CH-1 microphone input in the lower left corner of the deck. (The
microphone is usually stored in the cabinet along the left wall, with
the proper cord plug into the deck. It's got a 3-pin audio jack on the
end that connects with the microphone and a "phono" type jack on the
end that plugs into the deck.) When you hit the button, you're
recording audio. The tape does not preroll, it starts from right where
you are. The CH-1 AUDIO LEVEL knob controls the volume level that you
record at. I've had good results around 3 or 4, your milage may vary.
The needle on the gauge above the knob can go into the red zone on the
right occasionally, but should never "peg out" on the extreme right
side. Whenever it does so the recorded voice is disorted. It's easy to
incrementally record your narration, but it's hard to go back and fix
a mistake in the middle of things. I highly recommend that you check
after every edit to make sure that everything sounds right before
going on. (Note that the audio meter only works when you're actually
recording or the deck is at a full stop. It will not work when you're
in pause mode.) Also remember that when you're recording the speakers
must be turned all the way down or else you'll have feedback problems.
The complicated way to use the microphone is useful if you need to
do insert audio editing: that is, go back and fix something up in the
middle of a track. You use the the editing board to control exactly
where you want to record the signal. Plug the microphone into audio
input 4 in back of the audio mixer. Turn the pan knob to the middle.
Turn the editor switch knobs (the two leftmost ones) all the way down
to 0. You'll need to fiddle with many different knobs: the
"microphone" knob (presumably audio input 4) and the blue master knob
on the audio mixer, and the audio level knobs on the 3/4" record deck.
I've had good results with
- microphone knob: 6
- blue master knob: 4
- audio level knobs on 3/4" deck: 4
Your milage may vary, always check the tape after recording a little
bit to make sure it's both undistorted and loud enough. Make sure the
speakers are turned all the way down when you're actually recording to
avoid echo. Remember you'll have to turn them back up when checking
the sound levels.
Tone
If you are making a videotape with an audio track, it's nice to put 1
KHz tone on top of colorbars at the beginning of each segment. (Then
anyone who later might need to copy your tape onto a compilation can
easily set the audio levels.) To do this, set the Oscillator switch to
On. If you've set the editor switch to colorbars then the main audio
input should be empty, but you might have to turn off the laserdisc
inputs (i.e. pull the rightmost two knobs out). Polite video rack
users will set the Oscillator switch back to Off when finished.
Tamara Munzner & Phil Lacroute/Jan 5, 1996
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Last modified: Wed May 29 20:13:18 1996