Loudspeaker Test Report Manufacturer: System Sensor Type: Recessed ceiling Model: SPSCW For: System Sensor Report No.: R1843/LS/SPSCW Prepared By: C.Nicolaides B.Sc July 2009 AMS Acoustics, London AMS Acoustics, London 1.00 Object 1.01 2.00 The object of this Report is to present measurements of the acoustic performance of the SPSCW device. Scope 2.01 The following characteristics were measured • • • • • On-axis (reference axis) frequency response Polar response Impedance Applied voltage On-axis 3rd octave band sound pressure level from which the following are calculated: (i) Directivity Index [dB], tabulated and graphical (ii) Directivity factor, Q (iii) Effective octave and wide band (100Hz to 10kHz) impedance (iv) Octave band Sensitivity [dB @ 1m, 1W/oct] (v) Wide band Sensitivity: dBA @ 1m, 1W dBlin @ 1m, 1W 250Hz-4kHz @ 1m, 1W Speech shape @ 1m, 1W (vi) Acoustic Power [dB-PWL @ 1W], tabulated and graphical (vii) Octave band Power Apportionment [%] (viii) Impedance bode plot (ix) Expected maximum Sound pressure level [dB @ 1m] (assuming no compression) (x) Frequency response chart (xi) Polar response charts. AMS Acoustics, London 3.00 4.00 5.00 Method 3.01 The device was mounted in Free Space as shown in figure 1 Mounting Method C. 3.02 The measurements were made in an anechoic chamber. 3.03 Measurements were made as detailed in AMS Test Method document No. IR/1a/LS/Meth. 3.04 All measurements were made in general accordance with BS EN 60268: Part 5: 2003. Results 4.01 The On-axis 3rd octave frequency response of the device is shown graphically. 4.02 The Impedance bode plot of the device is shown graphically. 4.03 Polar plots of the device are shown graphically. 4.04 Tabulated values of Directivity index, Directivity factor, Sensitivity, Acoustic Power, Power Apportionment, Impedance and Maximum SPL are shown in the Summary data sheet. 4.05 The Directivity Index has been calculated using Gerzon’ equal angle, weighted area method. Notes 5.01 Sensitivity The octave band sensitivity is produced in its useful form for calculations. It should be noted that the octave band sensitivity is given as dB @ 1m, 1W/Oct. To determine the output when only the overall power is known, then only the overall dBA or dBlin values should be used. For more detailed information, refer to AMS Acoustics Data Sheet ‘Loudspeaker Sensitivity – Interpretation of Results’. 5.02 Polar Plots For convenience, each polar plot has been normalized to 0dB. For this reason, caution is advised when comparison of levels between octave bands are made. The reference axis frequency response should be used for comparison purposes. AMS Acoustics, London 6.00 Engineers Notes & Observations The reference point is located at the centre of the loudspeaker, in line with the baffle board. The reference axis is normal to the grille, in line with the reference point. The impedance does not fall to below 80% of the rated impedance within the frequency range 89Hz to 11.2kHz. AMS Acoustics, London Loudspeaker Information Manufacturer : Model Code : Type : Colour : Serial No. : Batch No. : Other Markings : Backbox : Grille : Weight (grams) : Depth (mm) : Width (mm) : Height (mm) : Special Features : System Sensor SPSCW Recessed ceiling White NM NM NM As supplied As supplied 760 76 mm 172 mm 172 mm Strobe light. Internal Details Driver Types/Sizes : Driver Serial No.(s) : Driver Markings : Damping Material : Available Tappings : NM NM NM NM 70.7V: 0.25W, 0.5W, 1W, 2W Electrical Details Resonant Frequency(s) : Cross-Over Frequency(s) : Nominal Impedance (ohms): Inductance : Capacitance : See impedance plot NA 2500 NM NM NM = Not Measured, NA = Not Applicable AMS Acoustics, London Manufacturer : Model Code : Mounting : Transformer Tapping : Effective Impedance : Measurement Distance : System Sensor SPSCW HalfSphere 2W 2824 1.4m Reference Axis Located at : 0 degrees Frequency (Hz) Parameter Axial Q Directivity Index (dB on Axis) Sensitivity (dB @ 1m, 1W/Oct) Sensitivity(dB @ 1m, 1W)250Hz-4kHz Sensitivity(dB @ 1m, 1W)Speech Shape Acoustic Power (dB-PWL @ 1W) Apportioned Power (%) Effective Impedance (Ohms) Expected maximum SPL (dB @ 1m) 125 1.1 0.4 73 250 1.7 2.3 89 500 1.5 1.8 82 1k 1.3 1.1 82 2k 4.6 6.6 94 4k 4.7 6.7 91 8k 3.5 5.4 84 75 15 2535 68 89 14 2884 83 83 15 2543 77 84 15 2443 77 90 15 2602 89 86 13 2965 85 80 11 3964 77 Test Signal: Pink noise(100Hz-10kHz, 3rd octave bands) Directivity Index 25 20 dB 15 10 5 0 -5 -10 125 250 500 1k 2k 4k 8k Frequency, Hz Acoustic Pow er dB-PWL @ 1W 105 100 95 90 85 80 75 125 250 500 1k Frequency, Hz 2k 4k 8k dB dBA 89 90 86 89 90 82 92 92 AMS Acoustics, London SPSCW Band Limited Frequency Response (Norm alised to 0dB) 5 0 Relative Level, dB -5 -10 -15 -20 -25 -30 -35 -40 63 125 250 500 1000 2000 4000 8000 16000 IEC 3rd-Octave Frequency, Hz Impedance Bode Plot 6000 90 75 5000 60 Impedance, ohms 4000 30 15 3000 0 -15 2000 -30 -45 1000 -60 -75 0 1 10 100 Frequency, Hz 1000 -90 10000 Phase Angle, degs 45 AMS Acoustics, London SPSCW 125Hz 250Hz 0 0 340 330 320 310 Left & Bottom 300 350 0 10 20 Right & Top 30 40 -10 50 290 70 -30 270 -40 260 250 80 280 90 270 100 260 Horizontal 190 180 170 160 300 50 110 120 130 220 140 210 200 Vertical 190 180 20 330 320 310 30 50 260 250 80 280 90 270 100 260 230 170 160 180 70 110 240 120 230 220 130 140 200 190 30 330 320 40 50 -40 260 250 80 280 90 270 100 260 230 220 160 70 110 120 220 30 130 210 330 320 40 60 180 170 160 140 260 250 280 90 270 100 260 110 240 120 230 130 220 140 170 160 150 340 350 0 10 20 30 40 -10 50 60 - 20 290 80 -40 180 190 300 70 -30 190 200 150 310 290 200 90 100 0 20 -20 210 80 -40 230 50 270 60 A-Weight 10 310 280 40 -30 150 -10 300 30 50 0 330 320 20 -10 -20 8kHz 0 10 240 130 140 170 350 0 250 120 350 160 290 110 240 340 300 70 340 170 310 60 180 180 150 0 20 -30 190 90 100 210 290 200 80 -40 140 -20 210 60 4kHz 10 -10 270 40 50 0 280 30 -20 2kHz 300 20 -10 -30 130 150 10 250 120 340 150 290 110 240 340 350 0 300 60 -40 330 320 310 160 1kHz 10 40 350 0 170 0 0 70 210 200 190 90 100 240 -30 220 80 -40 230 290 270 60 70 150 -20 280 40 -20 500Hz 350 0 340 330 320 -10 310 30 -30 130 140 210 200 20 -10 250 120 230 220 10 290 110 240 340 300 60 -20 280 330 320 310 350 0 70 - 30 80 90 - 40 100 250 110 240 120 230 130 220 140 210 200 190 170 160 180 150 AMS Acoustics, London SPSCW Wide Band Frequency Response Note: The wide band frequency response is derived using MLS methods and does not necessarily relate to the sensitivity values given in the summary table. Signed: Countersigned: AMS Acoustics, London Loudspeaker Mounting Methods Backbox Driver & Grille Mounting Method A Loudspeaker Mounted in a Reflective Baffle Mounting Method C Loudspeaker Mounted on a Reflective Baffle Mounting Method B Loudspeaker Mounted in an Absorbent Baffle Mounting Method B Loudspeaker Mounted on an Absorbent Baffle Mounting Method E Loudspeaker not Attached to any Surface and Radiation Unaffected by nearby Reflecting Surfaces