Background -- What is PWM?, Heat Generation

JVC RX-D401 Background -- What is PWM?, Switching Power Supply with Highly-Efficient Operations

Hybrid Feedback Digital Amplifier

JVC technologies for satisfying theBackgroundTHX Ultra2 certification-- What is PWM?

Background -- What is PWM?

RX-D702 RX-D402

*Also applies to RX-D401

Pulse Width Modulation (PWM) is a method of digitally encoding analog signal levels. In the process, continuously varying value of input audio signals is detected based on the reference voltage (Vref) by comparing the signals with triangular waves. When the value is higher than Vref level, the pulse is switched “ON”, and when it gets below Vref, it’s turned “OFF”. The higher than Vref the value is, the longer the pulse is kept “ON”. The lower than Vref the value is, the longer the pulse is left “OFF”. Thus, square-shaped waves are generated, representing either “ON” or “OFF” state of the pulse -- length of the “ON” and “OFF” pulses expresses the value of audio signals with respect to the Vref levels. These waves are called “PWM signals”. Precision of the PWM signals is one of the elements that determine the sound quality delivered by a digital amplifier. This is why “feedback” process is essential for delivering high-quality sound.

Switching Power Supply with Highly-Efficient Operations

OFFON

Power MOS FET

Switch

●Heat Generation

1.Loss from ON Impedance

2.Switching Loss

PWM (Pulse Width Modulation)

	ON	+1
	ON	+1
		+1
	OFF
		0
	OFF

Generation of PWM Signals

1.Values of input audio signals are detected by comparison with triangular waves.

2.High-precision triangular waves are necessary.

Input Audio

Signals Comparator

ON	-1	-1

Triangular

Waves

PWM

< 44 >

RX-D401, RX-D402, RX-D702 specifications

The JVC RX-D702, RX-D402, and RX-D401 are remarkable receivers that exemplify JVC's commitment to delivering high-quality audio and advanced technology for home entertainment. Each model presents distinct features while maintaining a strong foundation of performance, making them suitable for various listening needs.

The JVC RX-D702 serves as a flagship model, offering exceptional audio quality and a plethora of connection options. It supports Dolby Atmos and DTS:X, providing an immersive sound experience that enhances movies, music, and games. The receiver supports 4K HDR video pass-through, ensuring high-resolution visuals. Featuring Wi-Fi connectivity, the RX-D702 allows instant streaming from various music services and seamless integration with smart home devices. The intuitive on-screen interface and remote app make navigation simple, providing users with easy access to settings and configurations.

In standby mode, the RX-D702 features low power consumption, a key consideration for eco-minded consumers. The model also showcases a robust power rating, ensuring it delivers dynamic sound with strength and clarity across different audio formats. Equipped with multiple HDMI inputs, audio and video signal routing becomes effortless, making it a perfect solution for multi-device setups.

The JVC RX-D402 is designed for users who desire powerful audio features without the extensive capabilities of the RX-D702. While it doesn’t support the latest surround sound formats like Dolby Atmos, it provides excellent stereo sound with a solid power output. The RX-D402 includes essential streaming services and Bluetooth connectivity, allowing users to enjoy music wirelessly from devices. Its compact size makes it ideal for smaller rooms where space may be a limitation.

Lastly, the RX-D401 remains a user-friendly receiver, appealing to budget-conscious consumers who still want quality performance. It offers essential audio performance and basic connectivity options, including Bluetooth and USB inputs. The RX-D401 is perfect for casual listeners who enjoy music without the complexity of advanced surround sound formats.

In summary, the JVC RX-D702, RX-D402, and RX-D401 offer a variety of features and technologies, catering to all kinds of audio preferences. From the high-end capabilities of the RX-D702 to the straightforward functionality of the RX-D401, JVC's receivers ensure impressive sound quality tailored to different environments and user needs.