Athena

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Athena
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Athena
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Athena

• SYSTEM
• 3.5-Way self-powered TMWWWW
• 37 X 7 X 16 mini tower
• built-in 4-channel amplifier per box
• time-aligned, transient accurate
• sloped baffle (11 degrees)
• Equalized Quasi Sealed System (EQSS? )
• adjustable electronic baffle step compensation

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Athena

• DRIVERS
• Vifa D27TG-35-06 silk dome tweeter
• Vifa TC08WD49-08 3.5-inch midrange
• four McIntosh 5.25-inch woofers
• fs 55 Hz
• Vas 15.5 L
• Qts 0.35
• Xmax 2.5 mm

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Athena

• ACTIVE CROSSOVER
• 750 Hz and 4000 Hz first order electrical
• 200 Hz constant-voltage half-way cross
• twin-tee passive 9 kHz midrange notch
• EQSS? biquadratic LF equalizer
• electronic Baffle Step Compensation
• adjustable BSC (amount and frequency)
• signal sense for auto turn-on

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Athena

• AMPLIFIERS
• four 125 Watt power amplifiers per box
• MOSFET output with JFET input
• boosted driver supply for max headroom
• flying catch diodes for non-saturating clip
• symmetrical, stick-free clipping
• high current design stable to lt 2 ohms
• clip indicator

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Athena

• AMPLIFIERS (cont.)
• folded complementary push-pull driver
• fast, low-voltage output stage drivers
• servo-controlled output offset
• no capacitors or inductors in the signal path
• small physical size
• 70 V/us slew rate
• lt 0.03 THD to 20 kHz _at_ full power

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Athena

• AMPLIFIERS (cont.)
• Flying Catch Diodes
• limit max gate-source voltage
• prevent driver saturation in clipping
• provide adaptive symmetrical clipping
• prevent saturation of folded EF drivers
• prevent reverse base breakdown in EF drivers
• prevent driver damage from output device short

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Athena

• EQSS? System
• objective - big sound from small box
• 9 liters per 5.25-inch woofer
• 53-Hz woofer f0
• box tuned to 37 Hz
• - 3dB _at_ 35 Hz, second order, Q0.7

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Athena

• EQSS? THEORY
• Quasi Sealed System
• ported, but box tuned very low
• resulting response approximates sealed system
• Equalize as if a sealed system
• use parameters of sealed system it approximates
• port increases LF excursion-limited SPL
• transient response like that of sealed system
• applicable to subwoofers as well

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Athena

• POWER MANAGEMENT
• auto turn-on at signal detect
• 5 minute on time in absence of signal
• inrush current control
• speaker relay delay control