JBL M9500 owner manual 100

Page 6

The directivity index (DI) of the H9500 horn is shown in Figure

5.The smoothly rising DI is a consequence of the gradual narrowing of the vertical dispersion angle above 2 kHz and contributes to the overall flatness of the high-frequency response of the system.

DirectivityIndex, DI(dB)

20

 

 

 

 

 

 

 

 

 

Q

 

 

 

 

 

 

 

 

100

10

 

 

 

 

 

 

 

 

10

DirectivityFactor,

 

0

 

 

 

 

 

 

 

 

1

 

 

20

50

100

200

500

1000

2000

5000

10000

20000

 

Frequency (Hz)

Overall system on-axis pressure response and impedance are shown in Figure 6. The contributions of the paralleled low- frequency sections and the high-frequency section are shown individually along with their acoustical summation. The overall slopes in the crossover region are a combination of electrical (network) and acoustical response.

 

 

 

 

 

 

 

 

 

 

 

 

M9500

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4.3V @ 1.5 m

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

HF @ "0"

 

 

 

 

 

 

 

 

100dB

 

 

 

 

 

 

 

Anecmoil

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Ground

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Plane

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

10 Ω

 

2

3

4

5

6

7 8 910

1.5

2

3

4

5

6

7 8 910

1.5

2

3

4

5

6

7 8 9 10

1.5

2

 

 

 

 

 

100

 

 

 

 

 

 

1000

 

 

 

 

 

 

10000

 

 

Figure 5. Plot directivity index (DI) and directivity factor (Q) of the H9500.

Figure 6. On-axis response of M9500. Individual contributions of paralleled low-frequency transducers and high-frequency section are shown, along with their summation. The impedance curve is also given, showing a minimum value of 3 ohms in the 100 Hz range.

The second and third harmonic distortion of the system is shown in Figure 7. Here, the system is driven with sine wave input to produce an output of 96 dB Lp at a distance of 1 meter. An output of 96 dB with a sine wave input corresponds to extremely high system output with wide band program material. Distortion curves have been raised 20 dB, and the val- ues seen here lie well below 1% for the lowest frequencies up to 4.5 khz, reaching a value of only 1.6% at 10 kHz. Not many loudspeakers can demonstrate such low levels of distortion as shown here.

96dB

M9500

 

Distortion Raised 20dB

Distortion

 

Solid = Second Harm.

3.0V @ 1 m

 

Dash = Third Harm.

 

Figure 7. Second and third harmonic distortion for fundamental of 96 dB Lp at a distance of 1 meter. (Distortion raised 20 dB)

2

3

4

5

6

7 8 910

1.5

2

3

4

5

6

7 8 910

1.5

2

3

4

5

6

7 8 9 10

1.5

2

 

 

 

 

 

100

 

 

 

 

 

 

1000

 

 

 

 

 

 

10000

 

 

Image 6
Contents M9500 General System Description Unpacking and Inspection System Setup Electronic OptionsTransducers Typical System Performance Measurements 100 Care and Maintenance of the System System Specifications Acoustic and Electrical Specifications800 645