JBL Technical Note - Vol.1, No.1 电路原理图.pdf

Technical Notes Vol. 1, No. 1 Performance Parameters of JBL Low-Frequency Systems Introduction This technical note will enable sound contractors and consultants to specify JBL LF enclosures, transducers and packaged systems to fit particular requirements. While most of the listed parameters are straightforward, some of them deserve special comment. Parameter 3 states the primary use of the system. Those indicated for reinforcement are to be used primarily for fixed-installation speech reinforcement applications. Those indicated for monitor LF or theater VLF are to be used for high-level LF performance in recording studio control rooms or motion picture theaters, for response down to 25 Hz. The general term Ml means that the system is intended for electronic musical instrument or amplified instrument use. Those systems indicated for high-level music reinforcement are intended for upper-bass or lower mid-range in those applications where HF horn components must be crossed over in the 1200-to-1500 Hz range. Parameter 6 is the JBL traditionally conservative sine wave power rating. Program ratings are easily 3 dB greater, and transient program peaks up to 10 dB above the steady-state rating can be tolerated. Parameter 7, the half-space reference efficiency of the system, assumes that the system will be placed next to a single reflecting surface. In Parameter 9, free-field ratings averaged over the system bandwidths are given.The band width of a system extends from its 3 dB down point up to its recommended crossover frequency. An additional rating gives the maximum output to be expected in a reference reverberant environment with a room constant (R) of 18.6 m 2 or 200 ft2. These ratings may easily be manipulated to give the reverberant SPL in rooms with other values of R using the following equation: New SPL=Reference SPL-10 log (R/18.6), where R is the new room constant in m 2. The beamwidth data of Parameter 12 gives the 6-dB down included angle in both horizontal and vertical planes at the usual crossover frequencies of 500,800 and 1200 Hz. Both directivity index (Dl) in dB and directivity factory (Q) are given at those frequencies. The Systems In addition to standard JBL systems, we present a number which are based on enclosures that JBL does not build, but for which JBL supplies construction plans. These are the low-mid horn (systems 18 through 21), which make use of either 300 mm (12) or 380 mm (15) drivers, depend ing on the application. The W horn is intended for music reinforcement applications, and the 340 L Sub-woofer is intended for theater use. Note for this system that there are two values of lower frequency limits. Those values given in parentheses require a different enclosure tuning and an appropriate electrical boost in the LF cut-off region, which can be provided by the JBL Model 5234A Electronic Dividing Network. Details of this are included in the plans. Finally, we present data on the models 4520 and 4530 rear-loading horns no longer made by JBL. Parameters 1 2 3 4 5 1. Enclosure 4507 4508 4518 4518 4518x2 2. Transducer Model 2225H 2225J 2240H 2245H 2245H Diameter 380 mm (15) 380 mm (15) 460 mm (18) 460 mm (18) 460 mm (18) Quantity 1 2 1 1 2 3. System Application Reinforcement Reinforcement Reinforcement Monitor LF; Monitor LF; System Application Theater VLF Theater VLF 4. System Impedance (ohms) Nominal 8 8 8 8 4 Minimum 7.3 7.0 7.3 7.1 3.6 5. Sensitivity (1W 1 m) 97 dB 100 dB 98 dB 95 dB 98 dB 6. Continuous Power Rating, watts 200 W 400 W 300 W 300 W 600 W 7. Half-space Efficiency 3.5% 7% 5% 2.1% 4.2% 8. Maximum Continuous Acoustical Power 7 W 28 W 15 W 6.2 W 24.8 W 9. Maximum Continuous SPL Free Field 3 m (100 110 dB 116 dB 113 dB 110 dB 116 dB Free Field 30 m (1000 90 dB 96 dB 93 dB 90 dB 96 dB Reverberant Field, R - 18.6 m 2 (200 ft2) 122 dB 128 dB 125 dB 122 dB 128 dB 10. Lower Frequency Limits - 3 dB 45 Hz 45 Hz 50 Hz 35 Hz 35 Hz -10 dB 35 Hz 35 Hz 30 Hz 25 Hz 25 Hz 11. Recommended Upper Crossover Frequency 1200 Hz 800 Hz 800 Hz 100 Hz 100 Hz 12. Beamwidth (-6 dB) 500 Hz (Hor.) 140 140 125 - 500 Hz (Vert.) 140 100 125 - DI (Q) 500 Hz 6 dB (4) 8 dB (6) 7 dB (5) - 800 Hz (Hor.) 90 90 75 - 800 Hz (Vert.) 90 50 75 - DI (Q) 800 Hz 9 dB (8) 10 dB (10) 13 dB (20) - - 1200 Hz (Hor.) 70 - - - 1200 Hz (Vert.) 70 - DI (Q) 1200 Hz 10 dB (10) - 13. Enclosure Data Volume, L (ft 3) 145 (5) 225 (8) 225 (8) 225 (8) - HxWxD, mm (in) 775 x 546 x 448 1060 x667x464 1060 x667x464 1060 x667x464 - (30 1/2 x 211/ 2 x 17 5/8) (39 3/4x26V2Xl7V 4) (39 3/4x26V 2x17V4) (39 3/4x26V2Xl7V4) Weight, kg (lb) 36(80) 69 (152) 63 (138) 63 (138) Direct Radiator P o 6 7 8 9 10 11 12 4518x4 4625 4695 Sub-woofer 4560 4560 4560 340 L (12 ft 3) 2245H E140-8 E155-8 2245H 2220H 2225H E140-8 460 mm (18) 380 mm (15) 460 mm (18) 460 mm (18) 380 mm (15) 380 mm (15) 380 mm (15) 4 1 1 1 1 1 1 Monitor LF; MI MI Theater VLF; Reinforcement Reinforcement MI Theater VLF Monitor LF 8 8 8 8 8 8 8 7.1 6.5 7.3 7.1 7.3 7.3 6.5 101 dB 100 dB 100 dB 95 dB 107 dB 103 dB 104 dB 1200 W 200 W 300 W 300 W 100 W 200 W 200 W 8.4% 4.9% 4.9% 2.1% 16% 6.4% 12.8% 99.2 W 9.8 W 14.7 W 6.3 W 16 W 12.8 W 25.6 W 122 dB 113 dB 115 dB 110 dB 117 dB 116 dB 117 dB 102 dB 93 dB 95 dB 90 dB 97 dB 96 dB 97 dB 134 dB 123 dB 125 dB 122 dB 125 dB 124 dB 127 dB 30 Hz 25 (20) Hz 120 Hz 120 Hz 120 Hz 20 Hz 18 (15) Hz 45 Hz 45 Hz 45 Hz 100 Hz N/A N/A 50 Hz 800 Hz 800 Hz 800 Hz 140 125 90 90 90 - 140 125 - 70 70 70 - 6 dB (4) 7 dB (5) - 9 dB (8.5) 9 dB (8.5) 9 dB (8.5) - 90 75 - 90 90 90 - 90 75 - 60 60 60 - 9 dB (8) 13 dB (20) 11 dB (12) 11 dB (12) 11 dB (12) - 70 65 - - 70 65 - - 10 dB (10) 12 dB (16) 127 (4.5) 283 (10) 338 (12) _ _ - 767x512x478 1021x751x478 533x1117x737 914x762x606 914x762x606 914x762x606 (30 3/i6x20Vex1813/i6) (40 3/i6x299/iex1813/i6) (21x44x29) (36x30 x2378) (36x30 x23 7/e) (36x30 x23 7/e) 28 (61.5) 36.6 (80.5) 69 (152) 51.4 (113) 51.1 (112) 51.1 (112) ted Systems 13 14 15 16 17 18 4560 4550 4550 4550 4550 Low/mid Horn E145-8 2220H/J 2225H/J E140-8/16 E145-8/16 E120-8 380 mm (15) 380 mm (15) 380 mm (15) 380 mm (15) 380 mm (15) 300 mm (12) 1 2 2 2 2 1 Ml Reinforcement Reinforcement MI MI High-level music reinforcement 8 4/8 4/8 4/8 4/8 8 7.0 3.7/7.5 3.7/7.3 3.3/6.5 3.3/6.5 7.5 103 dB 108 dB 106 dB 107 dB 106 dB 107 dB 150 W 200 W 400 W 400 W 300 W 150 W 8% 20% 8% 16% 10% 20% 12 W 40 W 32 W 64 W 30 W 30 W 115 dB 121 dB 122 dB 123 dB 121 dB 119 dB 95 dB 101 dB 102 dB 103 dB 101 dB 99 dB 124 dB 129 dB 128 dB 131 dB 128 dB 128 dB 120 Hz 80 Hz 80 Hz 80 Hz 80 Hz 140 Hz 45 Hz 40 Hz 40 Hz 40 Hz 40 Hz 60 Hz 800 Hz 800 Hz 800 Hz 800 Hz 800 Hz 1500 Hz 90 80 80 80 80 70 70 100 100 100 100 90 9 dB (8.5) 11 dB (12) 11 dB (12) 11 dB (12) 11 dB (12) 9 dB (8.5) 90 75 75 75 75 60 60 30 30 30 30 90 11 dB (12) 14 dB (25) 14 dB (25) 14 dB (25) 14 dB (25) 11 dB (12) - 50 - 60 12 dB (15) 914x762x606 914x1524x825 914x1524x825 914x1524x825 914x1524x825 609x429x762 (36x30 x23%) (36x60 x32V2) (36x60 x32V2) (36x60 x32V2) (36x60 x32V2) (17V2x24x30) 62 (136) 109 (240) 108 (238) 108 (238) 114 (251) 38.6 (85) Special Horn Systems P o r t e d H o r n S y s t e m s Special H o r n S y s t e m s 19 20 21 22 23 24 25 Low/mid Horn Low/mid Horn Low/mid Horn W Horn W Horn 4520 4530 2202H E145-8 2225H E155-8 2240H E140-8/16 E140-8 300 mm (12) 380 mm (15) 380 mm (15) 460 mm (18) 460 mm (18) 380 mm (15) 380 mm (15) 1 1 1 1 1 2 1 High-level music High-level music High-level music MI MI MI MI reinforcement reinforcement reinforcement 8 8 8 8 8 4/8 8 6.5 6.7 7.3 7.3 7.3 3.3/6.5 6.5 106 dB 103 dB 103 dB 104 dB 104 dB 107 dB 104 dB 150 W 150 W 200 W 300 W 300 W 400 W 200 W 16% 8% 8% 15% 15% 16% 12.8% 24 W 12 W 16 W 45 W 45 W 64 W 25 W 120 dB 114 dB 115 dB 119 dB 117 dB 123 dB 117 dB 100 dB 94 dB 95 dB 99 dB 99 dB 103 dB 97 dB 127 dB 124 dB 125 dB 130 dB 130 dB 131 dB 127 dB 110 Hz 100 Hz 100 Hz 60 Hz 60 Hz 60 Hz 60 Hz 60 Hz 60 Hz 60 Hz 35 Hz 35 Hz 40 Hz 45 Hz 800 Hz, or 800 Hz, or 1200 Hz 800 Hz 800 Hz 300 Hz 300 Hz Full-Range Ml Full-Range Ml 70 70 70 60 60 100 140 90 90 90 45 45 140 140 9 dB (8.5) 9 dB (8.5) 9 dB (8.5) 13 dB (20) 13 dB (20) 8 dB (6) 6 dB (4) 60 60 60 -_ 50 90 90 90 90 - - 90 90 11 dB (12) 11 dB (12) 11 dB (12) - 10 dB (10) 9 dB (8) 50 50 50 - - - 60 60 60 - - 12 dB (15) 12 dB (15) 12 dB (15) 609x429x762 609x429x762 609x429x762 610 x1220 x610 610 x1220 x610 1276x908x756 1213x603x603 (17V2X24X30) (17V2x24x30) (17V2X24X30) (24x48x30) (24x48x30) (50 1Ax353/4x293/4) (47 3/4x233Ax233/4) 38.6 (85) 39.6 (87) 41.8 (92) 82.4 (180) 82.4 (180) 118 (260) 64 (141) Rear Loading H o r n s - 19 20 21 22 23 24 25 PROFESSIONAL DIVISION JBL Incorporateci, 8500 Balboa Boulevard, PO. Box 2200, Northridge, California 91329 U.S.A. UBL/barman international 2M 63809 6/84 Printed in U.S.A.