1. Microphones:
Design and Application
2009
Created By:
Brook Sutton

2. Introduction
Microphone
• first device in the
recording chain
• A transducer -
converts one form of
energy into another

3. Microphone Designs
THREE TYPES OF
MICROPHONES
Dynamic
Ribbon
Condenser

4. DYNAMIC MICROPHONES
ELECTROMAGNETIC
THE DYNAMIC MICROPHONE INDUCTION
whenever an
electrically conductive
metal cuts across the
flux lines of a magnetic
field, a current of a
specific magnitude
and direction will be
generated within the
metal

5. DYNAMIC MICROPHONES
ELECTROMAGNETIC
THE DYNAMIC MICROPHONE INDUCTION
whenever an
electrically conductive
metal cuts across the
flux lines of a magnetic
field, a current of a
specific magnitude
and direction will be
generated within the
metal

6. RIBBON MICROPHONES
ELECTROMAGNETIC
INDUCTION
uses a corrugated
thin aluminum
diaphragm
Very sensitive to
sound pressure

7. RIBBON MICROPHONES
ELECTROMAGNETIC
INDUCTION
uses a corrugated
thin aluminum
diaphragm
Very sensitive to
sound pressure

8. CONDENSER
MICROPHONES
ELECTROSTATIC
PRINCIPLE
consists of two very thin
plates - one moveable -
one stationary
acts like a capacitor -
varying changes in
voltage will occur as the
plate moves back and
forth

9. CONDENSER
MICROPHONES
ELECTROSTATIC
PRINCIPLE
consists of two very thin
plates - one moveable -
one stationary
acts like a capacitor -
varying changes in
voltage will occur as the
plate moves back and
forth

10. MICROPHONES
CHARACTERISTICS AND RESPONSE PATTERNS

11. DIRECTIONAL RESPONSE
SOUND
SOURCE
“On-Axis”
Sound source angles
directly into
diaphragm

12. OMNIDIRECTIONAL
900
“polar pattern”
show’s a mic’s
sensitivity with o0 1800
respect to direction
and frequency over
3600
2700

13. BIDIRECTIONAL
900
“figure eight pattern”
pressure gradient -
the pickup is 00 1800
responsive to relative
differences in
pressure between
the front, back, and
sides of the 2700
diaphragm

14. OTHER DIRECTIONAL
PATTERNS
CARDIOID PATTERN
Cardioid means
"heart-shaped",
which is the type of
pick-up pattern
these mics use.
Sound is picked up
mostly from the
front, but to a lesser
extent the sides as
well.

15. OTHER DIRECTIONAL
PATTERNS
HYPER-CARDIOID
PATTERN
This is exaggerated
version of the
cardioid pattern. It is
very directional and
eliminates most
sound from the
sides and rear.

16. MICROPHONES
Frequency Response

17. FREQUENCY RESPONSE
CURVE
The on-axis frequency-
response curve refers to
the measurement of the
microphones output over
the audible frequency
range.
A microphone that is
designed equally to all
frequencies is said to
exhibit a flat frequency-
response.

18. Rumble - high-level vibrations that occur at very low
frequencies. (usually between 3 to 25 Hz)
This phenomena can be avoided by using a “shock
mount”, choosing a mic that restricts those
frequencies, or by using a low frequency roll-off filter
Proximity Effect - This effect causes an increase in bass
response whenever a directional mic is brought within 1
foot of the sound source.

19. Transient Response - the measure of how quickly a mic’s diaphragm will
react when it is hit by an acoustic wave.
Sensitivity Rating - the output level that a microphone will produce -
microphones with a higher sensitivity rating will produce stronger output
signals
Equivalent Noise Rating - a device’s electrical self-noise; often referred to
as a hiss or hum
Overload Distortion - caused by extreme SPL levels. Most microphones
have a maximum of 140 dB. Many microphones employ a pad which
reduces the microphones output thereby eliminating overload distortion.
Impedence - output impedance is a rating used to match the output of
one device to the input of another device.

20. BALANCED/UNBALANCED
LINES
Balanced lines use three
wires to carry the audio signal:
two carry the signal voltage
(positive and negative), one
acts as a shield or ground
wire. Usually Low-Impedance
devices use this connection.
Two Types of Connectors:
TRS -(Tip Ring Sleeve)
XLR -also known as Three
Pin Connector

21. BALANCED/UNBALANCED
LINES
Unbalanced lines use two wires to
carry the audio signal: a single signal
lead carries the positive, a seconded
grounded shield completes the
circuits return path. Used by high
impedance and most line-level
devices.
Two Types of Connectors:
TS -(Tip Sleeve)
RCA - also known as a cinch
plug or phono plug. Developed
by the Radio Corporation of
America in the 1940’s. Still in use
today.

22. MICROPHONE PREAMPS
Microphone Preamps are
used to amplify the signal
that comes from most
microphones.
Most studios employ a
console that contains
preamps for each channel.
growing trend to stock
outboard preamps to
get a different sound
from a microphone

23. MICROPHONE PREAMPS
Microphone Preamps are
used to amplify the signal
that comes from most
microphones.
Most studios employ a
console that contains
preamps for each channel.
growing trend to stock
outboard preamps to
get a different sound
from a microphone

24. MICROPHONE PREAMPS
Microphone Preamps are
used to amplify the signal
that comes from most
microphones.
Most studios employ a
console that contains
preamps for each channel.
growing trend to stock
outboard preamps to
get a different sound
from a microphone

25. MICROPHONE PREAMPS
Microphone Preamps are
used to amplify the signal
that comes from most
microphones.
Most studios employ a
console that contains
preamps for each channel.
growing trend to stock
outboard preamps to
get a different sound
from a microphone

26. MICROPHONE PREAMPS
Microphone Preamps are
used to amplify the signal
that comes from most
microphones.
Most studios employ a
console that contains
preamps for each channel.
growing trend to stock
outboard preamps to
get a different sound
from a microphone

27. PHANTOM POWER
Some microphones
require a DC voltage of
+48V (volts) in order to
operate.
Most condenser
microphones require
a separate power
supply either from a
battery, console, or
Phantom Power
pack

28. PHANTOM POWER
Some microphones
require a DC voltage of
+48V (volts) in order to
operate.
Most condenser
microphones require
a separate power
supply either from a
battery, console, or
Phantom Power
pack

29. PHANTOM POWER
Some microphones
require a DC voltage of
+48V (volts) in order to
operate.
Most condenser
microphones require
a separate power
supply either from a
battery, console, or
Phantom Power
pack

30. PHANTOM POWER
Some microphones
require a DC voltage of
+48V (volts) in order to
operate.
Most condenser
microphones require
a separate power
supply either from a
battery, console, or
Phantom Power
pack

31. PHANTOM POWER
Some microphones
require a DC voltage of
+48V (volts) in order to
operate.
Most condenser
microphones require
a separate power
supply either from a
battery, console, or
Phantom Power
pack

32. PHANTOM POWER
Some microphones
require a DC voltage of
+48V (volts) in order to
operate.
Most condenser
microphones require
a separate power
supply either from a
battery, console, or
Phantom Power
pack

33. MICROPHONES
Techniques

34. FOUR FUNDAMENTAL STYLES
OF MICROPHONE PLACEMENT
FOUR TYPES OF
MICROPHONE
PLACEMENT:
Distant
Close
Accent
Ambient

35. DISTANT MIKING
It considered distant
miking when the
sound source is 3ft or
more from the
microphone.
Most often used to
pickup large
instrument ensembles,
add a live, open feeling
to a recorded sound

36. CLOSE MIKING
It considered close
miking when the
sound source is 1 inch
to 3 ft from the
microphone.
Used to record a
desired sound when
other sounds are
present simultaneously

37. ACCENT MIKING
It considered accent
miking when the
microphone is used to
enhance presence and
volume for a solo
instrument(s) among
an ensemble or
orchestra.
Often difficult to blend
in with a natural
balance in recordings.

38. AMBIENT MIKING
It considered ambient
miking when the
reverberant room is more
prominent than the direct
sound source.
Often used in stereo
recording, audience, a
hall where a performance
is being held, or in the
same room as a sound
source to create a sense
of space.

39. MICROPHONES
Stereo Miking Techniques

40. STEREO MIKING
TECHNIQUES
Stereo Miking refers to the
use of two microphones to
produce a coherent stereo
image.
FOUR TECHNIQUES:
Spaced Pair
X/Y
M/S
Decca Tree

41. STEREO MIKING:
SPACED PAIR
Spaced Pair stereo
miking refers to the use of
two microphones placed
in front of a sound source
spaced anywhere from a
few feet to 30 ft apart. In
this configuration there is
a strong potential for
phase discrepancies.

42. STEREO MIKING:
SPACED PAIR
Spaced Pair stereo
miking refers to the use of
two microphones placed
in front of a sound source
spaced anywhere from a
few feet to 30 ft apart. In
this configuration there is
a strong potential for
phase discrepancies.

43. STEREO MIKING:
X/Y
X/Y - stereo miking refers to
the use of two microphones
of the same brand and model
placed with their grills close
together generally between
900 and 1350. Both
microphones are set to
pickup in a Cardioid polar
pattern. (very common
technique)

44. STEREO MIKING:
X/Y
X/Y - stereo miking refers to
the use of two microphones
of the same brand and model
placed with their grills close
together generally between
900 and 1350. Both
microphones are set to
pickup in a Cardioid polar
pattern. (very common
technique)

45. STEREO MIKING:
X/Y
X/Y - stereo miking refers to
the use of two microphones
of the same brand and model
placed with their grills close
together generally between
900 and 1350. Both
microphones are set to
pickup in a Cardioid polar
pattern. (very common
technique)

46. STEREO MIKING:
M/S
M/S- (mid-side) stereo miking
utilizes two microphones with
different polar patterns. Similar
to X/Y with the exception that
one microphone is set to a Bi-
Directional polar pattern angled
90º toward the sound
sources. The front
microphone is set to a Cardioid
polar pattern and is angled
directly at the sound source.

47. STEREO MIKING:
M/S
M/S- (mid-side) stereo miking
utilizes two microphones with
different polar patterns. Similar
to X/Y with the exception that
one microphone is set to a Bi-
Directional polar pattern angled
90º toward the sound
sources. The front
microphone is set to a Cardioid
polar pattern and is angled
directly at the sound source.

48. STEREO MIKING:
M/S
M/S- (mid-side) stereo miking
utilizes two microphones with
different polar patterns. Similar
to X/Y with the exception that
one microphone is set to a Bi-
Directional polar pattern angled
90º toward the sound
sources. The front
microphone is set to a Cardioid
polar pattern and is angled
directly at the sound source.

49. STEREO MIKING:
DECCA TREE
DECCA TREE - this miking
technique is primarily used in
classical recording scenarios
however it can also be used in
studio situations. This technique
employs three microphones set
to Omnidirectional polar
patterns. The left and right
microphones are set 3 ft apart
while the third mic is placed
1.5 ft centered in front of the left
an right microphones.

50. STEREO MIKING:
DECCA TREE
DECCA TREE - this miking
technique is primarily used in
classical recording scenarios
however it can also be used in
studio situations. This technique
employs three microphones set
to Omnidirectional polar
patterns. The left and right
microphones are set 3 ft apart
while the third mic is placed
1.5 ft centered in front of the left
an right microphones.

51. STEREO MIKING:
DECCA TREE
DECCA TREE - this miking
technique is primarily used in
classical recording scenarios
however it can also be used in
studio situations. This technique
employs three microphones set
to Omnidirectional polar
patterns. The left and right
microphones are set 3 ft apart
while the third mic is placed
1.5 ft centered in front of the left
an right microphones.