ABOUT 9000 SERIES

Touring companies have always requested reduced weight and size of sound reinforcement systems, without compromising sound quality, narrowing the frequency range, and with the precise objective in mind of delivering the same, or even higher SPL, to the audience. At the same time, an audio contractor designer’s goal is to use the least intrusive audio systems possible, guaranteeing the highest possible quality of audio reproduction. Is there a possible solution? In theory the answer is simple: keeping constant the total weight and size of the audio system, you should increase the audio system efficiency, calculated as the electrical into acoustical energy transfer ratio. Unfortunately, turning this dream into reality is far more complex.

In the last ten years, amplifier technology has made a quantum leap in terms of watts per kilogram output. Today’s power amplifier energy capabilities are way beyond the potential of last century’s units, being able to manage accurately a tremendous output current in a compact package.
From the loudspeaker side, it was clear to Eighteen Sound that the market was rapidly changing, demanding transducers capable to take full advantage of these new amplifier’s power potential. In order to fulfill this requirement, it was necessary to develop a new generation of loudspeakers capable to manage very high power and consequently able to withstand increased mechanical stress, due to extremely high excursion requirements.

Our answer to this technological challenge is the 9000 series neodymium extended low frequency loudspeakers range. When compared to 4 inch voice coil diameter 18 inch and 21 inch models, the 9000 series exhibit more than twice the performances in terms of power handling and maximum SPL output capability.
In the below chart is shown, in a convenient graphic format, the working range area of a conventional design 4” voice coil 18” loudspeaker compared to our 18NLW9600 5,3” voice coil neodymium transducer. On the vertical axis is shown the loudspeakers membrane displacement (X), on the horizontal axis the program power delivered by the amplifier (Y).
We can use this graphic as a sort of acoustic energy calculator: the 18NLW9600 shows more than double the program power capability and almost double the displacement.

A very important part of efficiency in the loudspeaker is due to the power compression factor, that measures the loss in SPL output when the voice coil is heated up due to the current delivered by the amplifier’s output. When comparing the 18NLW9600 with a traditional technology loudspeaker at the same input power, power compression figures show an average reduction of almost 2 dB. Final result is an increased capability of generating impressive SPL when driven at extremely high power.
In the below chart, you will see that the highest generated SPL of an 18NLW9600 - blue plot - driven at maximum program power, exceeds by 3dB or more the one generated by a traditional design 18” loudspeaker acoustic output - red plot (1).

Notes

(1) Transducers were loaded in our standard test 180 liters cabinet tuned at 35Hz. A 2 x 2000W into 8ohm power amplifier was used for testing. One single channel has been connected to the conventional 18” transducer, while the 18NLW9600 was connected to the bridged unit – for a nominal 8kW maximum power. Seven log spaced tone burst measurements have been made, each one with a 200V peak value for the conventional unit, and with 380V peak value for the 18NLW9600. 180 Lit enclosure positioned at corner, pi/4 emission, floor microphone measurement.