Electronic musical instruments · audio · video equipment

Electronic musical instruments produce low-frequency waveform signals by electronic circuits. The environment is used in various places such as general homes, educational sites such as schools, and professional musicians.

With the electronic circuit, you can control the pitch, volume, and timbre, which are sound elements. There is a subtraction method of obtaining a timbre by filtering a periodic pulse train, an addition method of synthesizing harmonics by a sine wave like an organ, a modulation method typified by an FM sound source, and a recorded waveform. There are several methods, such as the PCM method, to store everything in the memory, like pitch. In the past, hardware synthesizers that used dedicated custom ICs as sound sources were mainstream, but in recent years, software and synthesizers have been on the rise.

According to one theory, the origin and history of electric musical instruments started with the invention of Denis D'Or using the electromagnet by Prokop · Divish in 1748, and after that, the electronic organ, the electric guitar, the analog synthesizer, the digital synthesizer, etc. Electric musical instruments are now in active age and appear in various places and scenes, such as the stage, educational sites such as families and schools, public areas such as stations, and so on.

It has been developed for various electronic musical instruments in different fields.

•    Electronic organ
•    Electone
•    Electronic Piano
•    Drum machine
•    keyboard
•    Amplifier
•    Guitar synthesizer
•    EWI

About the AC adapter used for electronic musical instruments

About safety standard

IEC / EN 60065 of the technical standard stipulated by the IEC stipulates that the designated equipment falls under. When acquiring the authentication, linear and switching-type power supplies apply.

About the difference point of safety application with communication equipment IEC / EC 60950

In the case of application and design for safety regulation, most communication equipment can be commonly used, but the difference points are listed below as a reference example.

① LPS request

    (Communication 60950): Evaluation measurement is essential
    (Acoustics 60065): No measurement required

② X electrolytic capacitor

    (Communication 60950): Residual voltage <37% is required after one second of disconnection
    (Acoustics 60065): After 2 seconds of breakdown, residual voltage Peak 35.0V or 60 V dc (judgment criteria with 60 V dc)

③ Temperate environment

    Leakage current: (communication 60950) 0.25 mA; (sound 60065) 0.5 mA request.

④ Tropical environment operating temperature

    (Communication 60950) 35 ° C (Subtract component specification 10K) (Acoustic 60065) 45 ° C (Subtract component specification 10K)

⑤ About the oil test (Softening Test)

This test is required only by the acoustic standard (UL).

Test reference method:

The designated part is put in oil, and the temperature starts at 100 ° C, rising by 50 ° C every hour until it becomes the verification test up to 175 ° C.

Testing Methods

There are four different methods used for this test.

Test results, case structure requirements:
For the case material, the thickness of the dent is <0.1 mm.

About product introduction and development cases

* We will give reference examples of some customers dealing with our products.

AC Power Adapter Development Project for Radio Products

In a development project for a radio product AC adapter commissioned by major manufacturer S Corporation, we faced a challenge when the initial prototype failed the safety standard application test. It was determined that the cause of this failure was the polycarbonate (PC) material used for the product casing, particularly failing the oil test.

In response to this challenge, we worked closely with our customers to thoroughly analyze the cause. We discovered that changing only the resin part connecting the metal AC pins while keeping the surrounding PC resin unchanged could clear the test, which successfully led to passing the test. This experience underscored the importance of combining different types of resin materials.

Our project on the radio product AC adapter provided valuable insights into the thermal effects of resins of the same material. We discovered that combining specific resin materials can effectively prevent heat-related physical deformation. This learning will enable us to handle similar issues more accurately and smoothly in future projects, demonstrating our commitment to continuous improvement.

Our extensive experience and technical expertise, cultivated through such development projects, are the pillars of our commitment to providing custom development tailored to our customers' needs and our expertise in compliance with safety standards. We are always ready to answer any questions you may have. Rest assured, based on the trust we receive from our customers, we are committed to providing even greater value.