61-C Galli Dr., Novato, CA 94949 415.883.8040
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SA 6” 2 Way Prototype 1
Measurement Data
61-C Galli Dr., Novato, CA 94949 415.883.8040
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This concept prototype Loudspeaker developed by Sausalito Audio uses a 6 ½” woofer sourced from Lavoce Italiana and 1” Audax dome tweeter. The box has a 2” rear firing port. For demonstrations, and these measurements, a Powersoft Ottocanalli DSP enabled amplifier is used. The crossover point is 1100Hz. The overall dimensions of the Conic Section Array waveguide used are 7 1/2”W x 4 1/2”H x 5 1/2”D.
This small CSA enabled loudspeaker is intended to show the extraordinary dispersion characteristics of Sausalito Audio’s waveguide in a relatively compact form factor and modest driver compliment. This concept prototype could become an outstanding studio monitor or consumer loudspeaker with the appropriate industrial design and electronics package.
All measurements were made at Sausalito Audio which does not have a full anechoic chamber. The data is anechoic to ~500Hz and becomes increasingly corrupted by room reflections below that. Below ~150Hz the data should be largely disregarded.
Figure 1: Spinorama chart for the SA 2 Way Prototype 1. For information on how to interpret this chart, please see
“Interpreting Spinorama Charts” on the SA web site.
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2 Way Prototype 1 Data Curves
Reference AxisListening WindowSound PowerEarly RelectionsDirectivity IndexDI Early Relections
61-C Galli Dr., Novato, CA 94949 415.883.8040
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Figure 2: Frequency response curves at the referenced horizontal angles. 0° vertical is taken as the center of the mouth of the waveguide. For CSA loudspeakers, it has been Sausalito Audio’s convention to use 20° horizontal, 0° vertical as the reference axis. The off-‐axis performance of the CSA waveguide obviates the need to “toe in” the
speaker.
Figure 3: The data from figure 2 normalized to the reference axis of 20° horizontal, 0° vertical to more clearly show
how the response of the speaker changes as one moves off the center line.
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dB S
PL
Frequency (Hz)
2 Way Prototype 1 Frequency Response
20H0V
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Frequency (Hz)
2 Way Prototype 1 Difference Curves
Normalized to 20dg Ref. Axis
20H0V
0H0V
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80H0V
61-C Galli Dr., Novato, CA 94949 415.883.8040
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Figure 4: Response curves for 10°, 20° & 30° above the 0° vertical reference which is the center of the waveguide.
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Figure 5: Response curves for 10°, 20° & 30° below the 0° vertical reference which is the center of the waveguide.
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dB S
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Frequency (Hz)
2 Way Prototype 1 Frequency Response
0H0V
0H10V
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0H30V
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Frequency (Hz)
2 Way Prototype 1 Frequency Response
0H0V
0H350V
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61-C Galli Dr., Novato, CA 94949 415.883.8040
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Figure 6: +10° & -‐10° vertical response normalized to 0° vertical reference axis to better show change over the 20°
vertical listening window.
Figure 7: Horizontal polar response at the indicated frequency. Data is normalized to 0dB and smoothed to 1/3
octave per convention for polar plots.
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Frequency (Hz)
2 Way Prototype 1 Difference Curves
Normalized to 0dg Ref. Axis
0H0V
0H10V
0H350V
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2 Way Prototype 11/3 Oct. SmoothedHorizontal Polar
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61-C Galli Dr., Novato, CA 94949 415.883.8040
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Figure 8: Horizontal polar response at the indicated frequency. Data is normalized to 0dB and smoothed to 1/3
octave per convention for polar plots.
Figure 9: Horizontal polar response at the indicated frequency. Data is normalized to 0dB and smoothed to 1/3
octave per convention for polar plots.
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2 Way Prototype 11/3 Oct. SmoothedHorizontal Polar
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2 Way Prototype 11/3 Oct. SmoothedHorizontal Polar
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14000 Hz18000 Hz
61-C Galli Dr., Novato, CA 94949 415.883.8040
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Figure 10: Vertical polar response at the indicated frequency. Data is normalized to 0dB and smoothed to 1/3
octave per convention for polar plots.
Figure 11: Vertical polar response at the indicated frequency. Data is normalized to 0dB and smoothed to 1/3
octave per convention for polar plots.
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2 Way Prototype 1Normalized1/3 Oct. SmoothedVertical Polar
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2 Way Prototype 1Normalized1/3 Oct. SmoothedVertical Polar
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61-C Galli Dr., Novato, CA 94949 415.883.8040
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Figure 12: Vertical polar response at the indicated frequency. Data is normalized to 0dB and smoothed to 1/3
octave per convention for polar plots.
Figure 13: The chart shows the -‐6dB point as a function of frequency and coverage angle.
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2 Way Prototype 1Normalized1/3 Oct. SmoothedVertical Polar
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-6 d
B B
eam
wid
th (d
egre
es)
Frequency
2 Way Prototype 1Beamwidth
Horizontal Beamwidth
Vertical Beamwidth