| Because of
the increased noise of analog recording, it becomes important for the
engineer to get the signal as close as it can be to a final sound before
the signal reaches the tape. If, for instance, you wanted to boost
the high frequencies, it would be important to add this equalization
before recording. If you waited for mixdown, you would be boosting
the tape hiss along with the desired signal. |
| But adding
equalization with the analog console causes phase distortion. As a
result, many engineers turn to micing techniques to achieve the final
sound on the multitrack tape, minimizing the use of equalizers. |
| Snap to The Snare |
| A good
snare drum sound has snap. During recording and mixing, one of the
first equalizers that an engineer reaches for is the one on the snare - to
make sure the snare has enough snap. The snare' snap is composed of
the stick hitting the head and the "rattle" of the snares
underneath the drum. A good snare drum sound has a quality of the
overtones (harmonics) caused by the skin. The final element of a
good snare drum sound is the body of the drum. |
| Figure 1a
shows a common placement of a microphone on a snare drum. Since the
microphone is towards the end of the skin, it produces good overtones of
the skin and picks up the snap of the stick hitting the head. The
microphone is angled to reject the high hat which is a loud drum kit
component near the snare drum. What the microphone does not pick up well
is the rattle and snap of the snares underneath the drum. The
recording engineer will usually use a board equalizer to boost the
"snap" of the snare drum with this microphone placement.
He/she is really making up for the fact that the snares of the drum are
not being picked up adequately. |
 |
| Figure 1a - Common Snare Micing |
|
| Figure 1b
shows the projection of sound from a snare drum. The body (lows) of the
drum are projected from the middle of the skin. The harmonics of the skin
(skin tone) are projected from the edge of the skin. The snare vibrations
transmit through the metal shell of the snare drum so that some of the
"snap" of the snare drum transmits from the shell and rim. The
main snare sound is projected underneath.
|
|
|
|
Figure 1b - Sound Projection Of Snare Drum |
|
| Figure 1c
shows an alternate method of micing the snare drum where the mic points
across the snare. This placement accents the skin tone and the snap of the
snare. Since the microphone does not reject the high hat properly, it has
the disadvantage of picking up more high hat leakage. This technique works
the best for drummers that hit the snare very hard.
|
|
|
|
Figure 1c - Alternate Micing |
|
| Figure 1d
shows a method of micing a snare where two microphones are used. The top
microphone is used to pick up the skin tone and body of the drum as well
as the stick sound. The bottom microphone picks up the snap of the snare.
Blending these microphones allows the snare sound to have body, skin tone
and snap in the desired proportions without the use of program
equalization.
|
|
|
|
Figure 1c - Two Mic Snare Pickup |
|
| The
engineer will often mix these microphones together before recording to the
analog recorder. While mixing the two microphones to get one sound,
it is usually necessary to use the phase reverse button on the channel
with the bottom snare microphone. If you didn't use this
phase-reversal, the snare sound could thin out because of phase
cancellation of the snare's lower frequencies.
|
| Electric Guitar:
|
| The
electric guitar has body, generating fundamental frequencies as low as 80
Hz. The "attack" sound of the instrument is at 3 - 5 kHz. A Lead
guitar will have important harmonics to 10 kHz. Figure 2a shows the
"standard" microphone placement on a guitar. The microphone is
placed close (2 inches) or so from one of the speakers in the amplifier
cabinet.
|
|
|
|
Figure 2a - Standard Electric Guitar Micing |
|
| A
microphone that will smoothly accent the "attack" is a
Sennheiser MD-421. The MD-421, however has severe proximity effect which
increases the bass frequencies and does so unevenly. Using the bass
roll-off switch on the microphone reduces the bass frequencies but leaves
the bass pick up uneven. A microphone that has extremely smooth low
end is the ElectroVoice RE-20. The Variable-D ports in this
microphone makes the microphone have much less proximity effect and have a
much smoother low-end. The microphone, however, does not accent the
attack of the guitar. When using one of these two microphones, the
program equalizer could be used to smooth out the low frequency pick up of
the MD-421 or accent attack frequencies for the RE-20. Program
equalization, of course, has the disadvantage of adding phase distortion.
|
| Another
technique is seen in figure 2b where two microphones are used to record
the guitar. The two heads of the microphones are kept extremely close
together so that there is no phase cancellation when the microphones are
mixed. The microphones are blended to achieve the qualities of both
microphones for the instrument. If an RE-20 microphone is used with a
MD-421microphone, the result is smooth body of the instrument with
increased attack.
|
|
|
|
Figure 2a - Two Mic Electric Guitar Pickup |
|
| Big, Clear Lead Guitars
|
| A good rock
lead guitar should sound "right there" and "big" (read
that as "Huge"). There should also be a clarity of the notes
being played. These factors create a conflict in how you place the
microphone to pick up the instrument.
|
| The
"big" sound of the guitar comes from placing a microphone
several feet away (10-15 feet). The clarity comes from a microphone being
placed very close to the speaker (2-5 inches). The distant microphone is
not clear and the close microphone is not big-sounding.
|
| If you
tried to use both a close and a distant mic, the clarity would get worse
because of the time difference between the microphones. Sound travels at a
speed of about 1/1000th of a second per foot. This makes the distant
microphone get its signal 10-15 ms. later than the close mic. This time
difference blurs the attack and clarity of the guitar.
|
| An advanced
technique is to use both microphones
but to delay the close microphone before blending the two mics. You would
want a delay unit that would delay the signal 10-15 ms and insert this in
the channel you use for the close mic. Now when you blend two mics, you
will get a sound that is both clear and big.
|
| Stereo Rhythm Guitars
|
| In
the last section we talked about big-sounding lead guitars. In a
three or four piece rock recording, the rhythm guitar also must sound big.
Using the same technique on 2 guitars to enhance the sound lowers the
distinction between the guitars. An alternate big guitar sound seems
to work well with rhythm guitars involves setting up two microphones to
pivk up the rhythm guitar sound, as shown in figure 3a.
|
|
|
|
Figure 3a - Two Mic Stereo Electric Guitar
Pickup |
|
| Some
engineers send the output of the two guitar microphones to two tracks as a
stereo image, sending (for instance) the closer microphone to a left track
and the more distant microphone to a track designated as right. If a
second rhythm guitar is recorded, the pans are reversed (sending the
closer microphone to a right track).
|
| A
more-enhanced stereo image can be obtained by patching the distant
microphone to two channels of the board. This makes the guitar on three
channels of the board: 1) Close Mic, 2) Distant Mic, 3) Distant Mic.
The engineer will then bring up all three guitar channels to the same
level and send them to odd (left) and even (right) busses of the
console. Phase reverse the second distant guitar channel. Pan
the distant guitar channels left & right as shown in figure 3b.
|
|
|
|
Figure 3b - Board Settings For Stereo Enhancement |
|
| The result is that thehe
guitar will have a stereo effect and sound huge. As different chords
(or notes) are sounded the sound will randomly come from different
directions.
|
Copyright 2001, Robert
Dennis, ALL RIGHTS RESERVED |