Transcript How Is Sound Produced?

How Is Sound Produced?
Tweeters Use Corona
Discharge to Produce
Sound
Corona is Produced by
Dielectric Breakdown Of Air
due to Extremely High
Voltages
Varying Voltage Causes
Size of Corona to Vary
Variation in Corona Affects
Surrounding Air Pressure
Causing Sound
Enhancements
More efficient use of power due to use of
modern semiconductors instead of
vacuum tubes.
Wider Frequency response Expected from
a higher power Efficiency
Smaller physical size of system.
Less heat radiated by components.
Coil Research
Forms resonant circuit
due to winding selfcapacitance
Coil wound with thick
wire to minimize resistive
loss.
Uses air-core coil for
minimal hysteresis.
Why Use Ion Tweeters?
Nearly perfect
transient response
Omnidirectionality


Normal tweeters beam
high frequencies,
distorting off-axis
sound.
Ion tweeters have
equal frequency
content in all
directions.
Specifications
Resonant high voltage oscillator
operates at ~9.1MHz.
Output voltage to sustain corona
discharge must be greater than 20,000
volts. 1 millimeter of corona forms for
every 2,000 volts above this reference.
Power consumption to be less than
200watts.
Oscillator Theory
The use of feedback
keeps the coil locked
in at its self-resonant
frequency.
The feedback signals
interrupts current via
the switching device.
The quickly changing
current in the coil
causes high voltage
to be produced.
Team Members
Group 21
Rob Alejnikov
Mark Blattner
Colin Joye
Specifications & Frequency Response
Gain

Variable from zero to 60
High Pass Filter

Cutoff at 2 kHz, 12 dB/octave
Low Pass Filter

Cutoff at 40 kHz, 12 dB/octave
Low Power Consumption

Consumes 0.36 Watts
High quality op-amps

LF356 audio op-amps
Advisors
Academia
Dr. Robert Caverly
Dr. Joseph Kozikowski
Dr. Pritpal Singh
Industry
Mr. Joseph Fell
Audio Subsystem Simulation