Nissan 28120NDS01 Nissan - Renault Speaker Common Design Features

The standard “Nissan 28120NDS01 Nissan - Renault common design specification for loudspeaker” developed by the Nissan automobile company specifies the requirements for performance testing of automotive loudspeakers, including loudspeakers with built-in amplifiers. This Nissan design specification standard specifies the performance and comparable characteristics of built-in loudspeakers.

For the purposes of this standard, loudspeaker means both loudspeaker unit and loudspeaker system. A loudspeaker system consists of a single or multiple loudspeaker unit including a baffle, enclosure, internal crossover network and other passive elements. All ratings and measurement results specified in this standard are obtained under meteorological and standard measurement conditions specified in the standard “JIS C 5532 Loudspeakers for sound system equipment”, excluding the environmental resistance test. If the supplier changes the conditions, these should be included in the bid drawings.

Before running the tests for all test items, provide the pink noise signal corresponding to the rated input of the speaker for 1 hour. Then, leave it at room temperature for 24 hours or longer.

In the Nissan 28120NDS01 standard, the ratings are explained as follows:

• Nominal impedance: The nominal impedance is selected from the R8601 series specified in the JIS Z 10 standard and described in the drawings. The lower limit of the impedance of the speaker should not fall below 80 percent of the nominal impedance in the nominal frequency band. Tolerances should be plus/minus 15 percent.
• Nominal and maximum inputs: Nominal and maximum inputs will be determined by Nissan and are described on the drawings. The nominal input must be greater than or equal to one third of the maximum input.
• Output sound pressure level: The output sound pressure level should be 88 dB/W/m or more and should be described on the drawings. The measurement frequency should be specified separately and the tolerances should be plus/minus 2 dB.
• Lowest resonant frequency: The lowest resonant frequency must be specified separately and explained in the drawings.
• Low and high frequency limits (effective frequency range): The values ​​must comply with the table given in the standard. Unless otherwise stated, the low frequency limit will be the lowest resonant frequency and the high frequency limit will be 10 dB lower than the output sound pressure level. The range between the low and high frequency limits will be defined as the effective frequency range and should be explained on the drawings.
• Frequency characteristics of the output sound pressure: The frequency characteristics of the output sound pressure should be specified separately and explained on the drawings.
• Directional characteristics of the output sound pressure: The directional characteristics of the output sound pressure shall be the frequency characteristics of the output sound pressure specified above in the angular directions of 30 degrees and 60 degrees with respect to the loudspeaker reference axis. They shall be measured simultaneously with the reference axis characteristics and the data shall be presented together with the data on the frequency characteristics of the output sound pressure. For oval loudspeakers, the values ​​shall be stated in the directions of the major and minor axes respectively.
• Deviation of frequency characteristics of output sound pressure: Deviation of frequency characteristics of output sound pressure should be 25dB or less in the effective frequency range.
• Harmonic distortion rate: Data on second and third order harmonic distortion rates should be presented.
• Polarity: When the sound pressure on the front surface of the speaker is increased, the terminal on the positive voltage side should be the positive terminal, and the terminal on the other side should be the negative terminal. If the speaker is turned upside down with the terminals facing the front, the terminal on the right side should be the positive terminal. When a connector is used, the terminal on the right (or top) side should be the positive terminal with the connector lock facing up. Connectors used for speakers should meet the following standards: “24014 NDS00 Direct-connect connectors” and “24014 NDS01 Direct-connect connector type 91 specification”.

Electrical performance tests defined in the Nissan 28120NDS01 standard include:

• Working test
• Abnormal noise test
• Maximum input voltage test
• Electrical impedance test (lowest resonance frequency test)
• Output sound pressure level test
• 2nd or 3rd order harmonic distortion testing
• Continuous load testing
• Abnormal noise test at maximum input voltage
• Instantaneous maximum input voltage test

Environmental resistance tests defined in the Nissan 28120NDS01 standard include:

• High temperature test (dry heat resistance)
• Low temperature test (cold resistance)
• High humidity operation test (moist heat resistance)
• High humidity exposure test
• thermal cycling test
• Light resistance test
• Vibration resistance test
• Impact resistance test (for application to door speakers)
• Compound corrosion test (for application to door speakers)
• Waterproof test (for door speakers)
• Bathtub test (for door speakers)
• Chemical resistance test (to be applied to speakers using plastic frames)
• Side impact test
• Flame retardancy (to be applied to speakers using plastic frames)

Among the numerous tests, measurements, analyses and evaluation studies that our organization has carried out for businesses in various sectors, it also provides testing services defined in the “Nissan 28120NDS01 Nissan - Renault speaker common design features” standard with its trained and expert staff and advanced technological equipment.