Transducers

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Transducers

• Microphones
• Loudspeakers

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Carbon Microphone
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Ribbon Microphones
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Ribbon Microphones

• Low Sensitivity
• Low Output
• Typically Limited Frequency Response
• Especially higher frequencies
• No Phantom Power!!!
• Typical Instruments
• Brass
• Bright Percussion
• Elec Guitar Amplifier
• Bright Steel String Guitar (Picked)

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Examples
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Moving Coil Microphones
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Moving Coil Characteristics

• Low Sensitivity
• Moderate Output
• Good Frequency Response
• No Powering Needed
• Typical Instruments
• Drums/Percussion
• Brass
• Live Sound Reinforcement
• Electric Guitar Amplifier

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Moving Coil Examples
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Condenser/Capacitor
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Capacitance
?E Q / ?C
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Condenser Microphones

• Most Sensitive Microphones
• Extremely Wide Frequency Response
• Typically High Output
• Can be quite small
• DC Charge Needed for Capacitor
• Phantom Powered Microphone
• Typically 48 Volts
• Electret Microphone

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Phantom Power

• Silently passes through mic cables
• How do you stop Phantom Power (DC)
• Pin 2 3 - Pin 1
• Sources
• Console / Microphone Preamplifier
• Phantom Power Supply Box

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Condenser Applications

• Where accuracy in transient response is desired.
• Distant microphone techniques.
• Stereophonic Microphone Techniques
• Multi-pattern microphones

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Condenser Examples
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Directional Characteristics
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BW Multipattern Mics
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BW Examples
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Ultradirectional Microphones
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Other Microphones
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STEREOPHONIC TECHNIQUES

• COINCIDENTAL
• NEAR COINCIDENTAL
• SPACED PAIR TECHNIQUES

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COINCIDENTALCHARACTERISTICS

• INTENSITY L/R INFORMATION ONLY
• NO TIME OF ARRIVAL
• VERY GOOD L/R STEREO
• NOT MUCH DEPTH

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COINCIDENTAL X,Y
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X,Y

• GOOD STEREO PICKUP
• OK MONO COMPATIBILITY
• MINIMAL ROOM AMBIENCE
• NOT MUCH DEPTH INFO
• GOOD CLOSE STEREO SETUP
• PIANO
• DRUM SET OVER-HEAD
• SOLO (OR MAIN) GUITAR
• SMALL ENSEMBLE

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M-S STEREO
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M-S STEREO

• GOOD STEREO PICKUP
• PERFECT MONO!
• GOOD ROOM AMBIENCE
• NOT MUCH DEPTH INFO
• BETTER THAN X,Y THOUGH
• GOOD CLOSE STEREO SETUP
• PIANO
• DRUM SET OVER-HEAD
• SOLO (OR MAIN) GUITAR
• SMALL ENSEMBLE

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BLUMLEIN STEREO
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BLUMLEIN

• GOOD STEREO PICKUP
• OK MONO
• VERY GOOD ROOM AMBIENCE
• BEST DEPTH INFO OF COINCIDENTAL
• GOOD FOR SMALL ENSEMBLE RECORDING IN A NICE SPACE
• PROBLEMS WITH BIG ENSEMBLES
• BACKUP SINGERS - POSSIBILITY

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NEAR - COINCIDENTALCHARACTERISTICS
INTENSITY L/R INFORMATION TIME OF ARRIVAL VERY
GOOD L/R STEREO EXCELLENT DEPTH NATURAL SENSE OF
SPACE
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ORTFOFFICE OF RADIO TELEVISION FRANCE
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ORTF CHARACTERISTICS

• GREAT STEREO PICKUP
• OK MONO
• EXCELLENT SENSE OF SPACE
• GOOD FOR SMALL ENSEMBLE RECORDING IN A NICE SPACE
• GREAT MAIN SYSTEM FOR ORCHESTRAL RECORDING
• CAN WORK AS SOLOIST PICKUP

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NOSDUTCH BROADCASTING
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NOS CHARACTERISTICS(SIMILAR TO ORTF)

• GREAT STEREO PICKUP
• OK MONO
• EXCELLENT SENSE OF SPACE
• GOOD FOR SMALL ENSEMBLE RECORDING IN A NICE SPACE
• GREAT MAIN SYSTEM FOR ORCHESTRAL RECORDING
• CAN WORK AS SOLOIST PICKUP

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SPACED MICROPHONETECHNIQUES
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AB PAIR
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OTHER SPACED TECHNIQUES

• ABC
• ABCDE
• DECCA TREE

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How do you choose the correct technique?

• How large is the ensemble?
• Is there a focal point, or not?
• Is there ambient noise in the room?
• Does the room have good acoustics? Do you want
  to capture the natural ambience/acoustics?
• Is Mono Compatibility Important? TV/Film/Radio?

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Microphone Placement Considerations

• Finding the sweet spot
• One ear for single microphone
• Head/two-ears for stereo microphone
• Proximity Effect
• Directional Microphone

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Microphone Placement Considerations 2

• Small Diaphragm vs. Large Diaphragm
• When to use?
• Condenser
• Electret
• Phantom-powered
• Moving Coil
• Ribbon

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Direct Box

• Unbalanced to Balanced
• Hi Z to Low Z
• 1/4-unbal to XLR-bal

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Direct Boxes(images are links)

• Active
• Passive

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Microphone Preamplifier

• Transparent (Grace 801)
• Color (TL Audio)