NOTES
TABULAR DA T A
1. Measurement/Data Processing Systems: Primary - FChart: proprietary EA W software;Secondary - Brüel & Kjær 2012.
2. Microphone Systems: Earthworks M30; Brüel & Kjær 4133
3. Measurements: Dual channel FFT; length: 32 768 samples; sample rate: 48 kHz; logarithmic sine wave sweep.
4. Measurement System Qualification (includes all uncertainties):SPL: accuracy +/-0.2 dB @ 1 kHz, precision +/-0.5 dB 20 Hz to 20 kHz, resolution 0.05 dB; Frequency: accuracy +/-1 %,
precision +/-0.1 Hz, resolution the larger of 1.5 Hz or 1/48 octave; Time: accuracy +/-10.4 µs, precision +/-0.5 µs, resolution 10.4 µs; Angular: accuracy +/-1°, precision +/-0.5°, resolution 0.5°.
5. Environment: Measurements time-widowed and processed to eliminate room effects, approximating an anechoic environment. Data processed as anechoic or fractional space, as noted.
6. Measurement Distance: 7.46 m. Acoustic responses represent complex summation of the subsystems at 20 m. SPLis referenced to other distances using the Inverse Square Law.
7. Volts: Measured rms value of the test signal.
8. Watts: Per audio industry practice, “loudspeaker watts” are calculated as voltage squared divided by rated nominal impedance. Thus, these are not True W att units of energy as defined by
International Standard.
9. SPL: (Sound Pressure Level) Equivalent to the average level of a signal referenced to 0 dB SPL = 20 microPascals.
10. Subsystem: This lists the transducer(s) and their acoustic loading for each passband. Sub = Subwoofer, LF = Low Frequency, MF = Mid Frequency , HF = High Frequency .
11. Operating Mode: User selectable configurations. Between system elements, a comma (,) = separate amplifier channels; a slash (/) = single amplifier channel. DSP= Digital Signal Processor.
IMPORTANT: T o achieve the specified performance, the listed external signal processing must be used with EA W-provided settings.
12. Operating Range: Range where the processed Frequency Response stays within -10 dB SPL of the power averaged SPLwithin this range; measured on the geometric axis. Narrow band
dips are excepted.
13. Nominal Beamwidth: Design angle for the -6 dB SPL point s, referenced to 0 dB SPLas the highest level.
14. Axial Sensitivity: Power averaged SPLover the Operating Range with an input voltage that would produce 1 W at the nominal impedance; measured with no external processing on the
geometric axis, referenced to 1 m.
15. Nominal Impedance: Selected 4, 8, or 16 ohm resistance such that the minimum impedance point is no more than 20% below this resistance over the Operating Range.
16. High Pass Filter: This helps protect the loudspeaker from excessive input signal levels at frequencies below the Operating Range.
17. Accelerated Life T est: System: Maximum test input voltage applied with an EIA-426B defined spectrum; measured with specified signal processing; Transducer: AES2-1984 R 1997.
18. Calculated Axial Output Limit: Highest average and peak SPLs possible during the Accelerated Life T est. The Peak SPLrepresents the 2:1 (6 dB) crest factor of the Life Test signal.
GRAPHIC DAT A
1. Resolution:To remove insignificant fine details, 1/12 octave cepstral smoothing was applied to acoustic frequency responses and 1/3 octave cep stral smoothing was applied to the
beamwidth and impedance data. Other graphs are plotted using raw data.
2. Frequency Responses:Variation in acoustic output level with frequency for a constant input signal. Processed: normalized to 0 dB SPL. Unprocessed inputs: 2 V (4 ohm nominal impedance),
2.83 V (8 ohm nominal impedance), or 4 V (16 ohm nominal impedance) referenced to a distance of 1 m.
3. Processor Response:The variation in output level with frequency for a constant input signal of 0.775 V = 0 dB reference.
4. Impedance: Variation in impedance magnitude, in ohms, with frequency without regard to voltage/current phase. This means the impedance values may not
be used to calculate True Watt s (see 8 above).
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