The Sony WH-1000XM4 headphones are an improvement over the previous generation Sony WH-1000XM3 headphones in several ways. Here are some of the key differences: 1. Improved noise-cancelling: The Sony WH-1000XM4 headphones feature an updated noise-cancelling algorithm that is more effective at blocking out external sounds, especially at higher frequencies. 2. Better voice detection: The Sony WH-1000XM4 headphones have better voice detection capabilities, which allows for more seamless integration with voice assistants like Amazon Alexa or Google Assistant. 3. Improved ambient sound mode: The Sony WH-1000XM4 headphones have an improved ambient sound mode that allows for more natural sound reproduction and better awareness of your surroundings. 4. Multipoint Bluetooth pairing: The Sony WH-1000XM4 headphones have the ability to pair with multiple devices at once, making it easier to switch between different devices without having to constantly disconnect and reconnect. 5. Speak-to-Chat feature: The Sony WH-1000XM4 headphones have a new feature called Speak-to-Chat, which automatically pauses playback and turns off noise-cancelling when you start speaking, making it easier to have a conversation without having to take off the headphones. While the improvements are noticeable, some users may still prefer the Sony WH-1000XM3 headphones for their lower price point and similar sound quality. However, for those who prioritize advanced noise-cancelling technology and improved features, the Sony WH-1000XM4 headphones are the better choice.